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Full-Text Articles in Engineering

An Application Of Deep Learning Models To Automate Food Waste Classification, Alejandro Zachary Espinoza Dec 2019

An Application Of Deep Learning Models To Automate Food Waste Classification, Alejandro Zachary Espinoza

Dissertations and Theses

Food wastage is a problem that affects all demographics and regions of the world. Each year, approximately one-third of food produced for human consumption is thrown away. In an effort to track and reduce food waste in the commercial sector, some companies utilize third party devices which collect data to analyze individual contributions to the global problem. These devices track the type of food wasted (such as vegetables, fruit, boneless chicken, pasta) along with the weight. Some devices also allow the user to leave the food in a kitchen container while it is weighed, so the container weight must also ...


Hf Iq Mixer Vfo Temperature Compensation And Drive Level Optimization For Opposite Sideband Suppression, Katlin Anne-Rostomyan Dahn Dec 2019

Hf Iq Mixer Vfo Temperature Compensation And Drive Level Optimization For Opposite Sideband Suppression, Katlin Anne-Rostomyan Dahn

Dissertations and Theses

An amateur radio 40m band temperature compensated variable frequency oscillator (VFO) with drive-level optimized for opposite sideband suppression for use as the local oscillator (LO) of a high frequency (HF) IQ image reject mixer is considered in this work. The first problem of this thesis was the discovery of the HF IQ mixer's opposite sideband suppression dependence on LO drive-level. As a solution to this problem, the author built a fixed drive-level VFO for the optimal opposite sideband suppression. This then led to the second problem of this thesis; the discovery by this author of the well-known problem of ...


A Review Of Integrated Propulsion, Suspension And Guidance Passive Guideway Maglev Technologies, Jonathan Bird Dec 2019

A Review Of Integrated Propulsion, Suspension And Guidance Passive Guideway Maglev Technologies, Jonathan Bird

Electrical and Computer Engineering Faculty Publications and Presentations

This paper provides a review of integrated propulsion, suspension and guidance maglev technology that use fully passive guideway structures.


Transmission-Scale Battery Energy Storage Systems: A Systematic Literature Review, Kevin Marnell, Manasseh Obi, Robert B. Bass Dec 2019

Transmission-Scale Battery Energy Storage Systems: A Systematic Literature Review, Kevin Marnell, Manasseh Obi, Robert B. Bass

Electrical and Computer Engineering Faculty Publications and Presentations

When the transmission capacity of an electrical system is insufficient to adequately serve customer demand, the transmission system is said to be experiencing congestion. More transmission lines can be built to increase capacity. However, transmission congestion typically only occurs during periods of peak demand, which occur just a few times per year; capitol-intensive investments in new transmission capacity address problems that occur infrequently. Alternative solutions to alleviated transmission congestion have been devised, including generation curtailment, demand response programs, and various remedial action schema. Though not currently a common solution, battery energy storage systems can also provide transmission congestion relief. Technological ...


Audio Beat Detection With Application To Robot Drumming, Michael James Engstrom Oct 2019

Audio Beat Detection With Application To Robot Drumming, Michael James Engstrom

Dissertations and Theses

This Drumming Robot thesis demonstrates the design of a robot which can play drums in rhythm to an external audio source. The audio source can be either a pre-recorded .wav file or a live sample .wav file from a microphone. The dominant beats-per-minute (BPM) of the audio would be extracted and the robot would drum in time to the BPM. A Fourier Analysis-based BPM detection algorithm, developed by Eric Scheirer (Tempo and beat analysis of acoustical musical signals)i was adopted and implemented. In contrast to other popular algorithms, the main advantage of Scheirer's algorithm is it has no ...


Environmental Information Content Of Ocean Ambient Noise, Martin Siderius, John Thomas Gebbie Sep 2019

Environmental Information Content Of Ocean Ambient Noise, Martin Siderius, John Thomas Gebbie

Electrical and Computer Engineering Faculty Publications and Presentations

In recent years, methods have been developed to estimate a variety of environmental parameters based on measurements of the ocean ambient noise. For example, noise has been used to estimate water depth using the passive fathometer technique and bottom loss estimated and used to invert for seabed parameters. There is also information in the noise about the water column sound speed, volume attenuation, and the sea-state. The Fisher information can be used to quantify the basic information available in the noise measurements and its inverse, the Cramér–Rao lower bound (CRLB), provides the lower limit on the variance of an ...


Modeling And Control Of Magnetic Gear Dynamics In A Wind Turbine Drivetrain, Danielle Vournas Sep 2019

Modeling And Control Of Magnetic Gear Dynamics In A Wind Turbine Drivetrain, Danielle Vournas

Dissertations and Theses

This thesis looks at the modeling and simulation of linear and nonlinear magnetic gear dynamics in a wind turbine drivetrain. The objective is to lay the groundwork for analysis, modeling and optimization of control structures focused on pole-slip prevention. A classical mechanical two-mass torsion spring model is used as the basis for developing the dynamic system equations and Simulink models. The wind turbine torque input to the low speed rotor is modeled as a disturbance input, the generator torque is modeled as a controlled input, and the high-speed rotor speed is the only measured output. The nonlinear dynamics are linearized ...


Drafting In Self-Timed Circuits, Christopher Lee Cowan Aug 2019

Drafting In Self-Timed Circuits, Christopher Lee Cowan

Dissertations and Theses

Intervals between data items propagating in self-timed circuits are controlled by handshake signals rather than by a clock. In many self-timed designs, a trailing data item will catch up with a leading item or token, even when it trails by thousands of gate delays. This effect, called "drafting," can be seen in many of the self-timed designs, e.g., GasP, Mousetrap, Click, and Micropipeline. The purpose of this dissertation is to reveal the circuit mechanism of drafting in self-timed circuits typically used in FIFO stages. Drafting is usually considered to be incidental to the operation of self-timed circuits since interval ...


Introducing Cornerstone Courses Into Electrical And Computer Engineering Curriculum, Branimir Pejcinovic Jul 2019

Introducing Cornerstone Courses Into Electrical And Computer Engineering Curriculum, Branimir Pejcinovic

Electrical and Computer Engineering Faculty Publications and Presentations

Almost all engineering programs have some form of final, culminating design experience, which is typically taught as a senior year capstone design course. Due to ABET requirements these are team and project based. Many programs will also have projects interspersed among required and elective courses, but these tend to be overrepresented in freshman year. We have recently introduced a set of courses during sophomore year that mimic our approach to capstone courses and provide authentic engineering design experience. These so-called cornerstone courses provide scaffolding by introducing all of the components of teamwork and design process but in a less formal ...


Large-Scale Der Aggregations Of Electric Water Heaters And Battery Inverter Systems, Kevin Marnell Jul 2019

Large-Scale Der Aggregations Of Electric Water Heaters And Battery Inverter Systems, Kevin Marnell

Dissertations and Theses

Distributed energy resources like residential electric water heaters and residential battery inverter systems offer a small amount of change to the grid individually. When aggregated however, these assets can cause major effects to the electric grid. Aggregating these resources allows them to take on generator-like functions with the ability to increment power and decrement power.

The Western Energy Imbalance Market is an energy market offering 15 minute and 5 minute markets for energy transactions between balancing areas. Generation assets make increment and decrement bids. Traditionally the only entrants to this market have been large scale generators and large scale assets ...


Analyzing Disparities In Ecosystem Services In U.S. Cities: The Relationship Between Tree Cover And Socio-Demographics, Katherine V. Cendrowski Jun 2019

Analyzing Disparities In Ecosystem Services In U.S. Cities: The Relationship Between Tree Cover And Socio-Demographics, Katherine V. Cendrowski

REU Final Reports

It is a generally accepted fact that trees, and vegetation in general, provide many benefits to human beings. What has not been so extensively studied is how those benefits may be distributed across the United States. This research project aims to study that distribution by modeling and analyzing the land use data of US cities and the socio-demographic data available. We are looking specifically at tree cover as presented in the National Land Cover Dataset (NLCD) in order to determine what the general demographics are of those people that live in closer proximity to trees. We are also looking at ...


A Resource Constrained Shortest Paths Approach To Reducing Personal Pollution Exposure, Elling Payne Jun 2019

A Resource Constrained Shortest Paths Approach To Reducing Personal Pollution Exposure, Elling Payne

REU Final Reports

As wildfires surge in frequency and impact in the Pacific Northwest, in tandem with increasingly traffic-choked roads, personal exposure to harmful airborne pollutants is a rising concern. Particularly at risk are school-age children, especially those living in disadvantaged communities near major motorways and industrial centers. Many of these children must walk to school, and the choice of route can effect exposure. Route-planning applications and frameworks utilizing computational shortest paths methods have been proposed which consider personal exposure with reasonable success, but few have focused on pollution exposure, and all have been limited in scalability or geographic scope. This paper addresses ...


Board 63: Work In Progress: Adapting Scrum Project Management To Ece Courses, Branimir Pejcinovic, Phillip Wong, Robert B. Bass Jun 2019

Board 63: Work In Progress: Adapting Scrum Project Management To Ece Courses, Branimir Pejcinovic, Phillip Wong, Robert B. Bass

Electrical and Computer Engineering Faculty Publications and Presentations

Scrum is a popular form of Agile project management. Its applications now include diverse areas such as software development, engineering, urban planning, and law. Scrum has also been used in software engineering educational programs, but its use in other engineering education is lagging. Within our electrical and computer engineering program, we introduced Scrum to help students improve their teamwork efficacy in projects and courses. Earlier, we have presented some initial experiences and observations when implementing Scrum in ECE courses. In this paper we will elaborate on how Scrum is applied across different years and how we scaffold student learning. Scrum ...


Aggregation Of Electric Water Heaters For Peak Shifting And Frequency Response Services, Thomas Leighton Clarke Jun 2019

Aggregation Of Electric Water Heaters For Peak Shifting And Frequency Response Services, Thomas Leighton Clarke

Dissertations and Theses

The increased penetration of renewable energy sources poses new challenges for grid stability. The stochastic and uncontrollable generation of solar and wind power cannot be adjusted to match the load profile, and the transition away from traditional synchronous generators is reducing the grid capacity to arrest and recover from frequency disturbances.

Additionally, the distributed nature of many renewable energy sources makes centralized control of generation more complicated. The traditional power system paradigm balances the supply and demand of electricity on the grid by regulating generation. As this becomes more difficult, one alternative is to adjust the load instead. This is ...


Physics-Based Signal Processing Methods For Terahertz Non-Destructive Evaluation Of Layered Media, Scott G. Schecklman Jun 2019

Physics-Based Signal Processing Methods For Terahertz Non-Destructive Evaluation Of Layered Media, Scott G. Schecklman

Dissertations and Theses

In recent years Terahertz (THz) time domain spectroscopy has emerged as a promising new technology with potential applications in a variety of fields, including industrial manufacturing, security screening and medical imaging. Pulsed THz systems are uniquely suited for non-destructive evaluation (NDE) of the sub-surface layers of dielectric packaging and coating materials, because they provide high dynamic range over a wide bandwidth in the far infrared portion of the electromagnetic spectrum. Often the dielectric materials of the packaging and/or surface coating layers exhibit relatively low loss and abrupt changes in the refractive index at the layer boundaries can be observed ...


Uhf And Microwave Phase-Modulated Scattering Array, Nasr Nomas Hussein Alkhafaji Jun 2019

Uhf And Microwave Phase-Modulated Scattering Array, Nasr Nomas Hussein Alkhafaji

Dissertations and Theses

This dissertation investigates the use an array of active nonlinear elements, with particular emphasis on controlling distortion products generated by nonlinear elements in space rather than using conventional ways such as transmission lines, waveguides, and power dividers and combiners. The nonlinear elements are made of assemblies of antennas and electronic switches, called modulated scatterers (MSs). These so-called MSs elements are utilized in a wide variety of applications such as radio frequency identification (RFID) systems, microwave imaging, Internet-of-Things sensors, etc. However, no research work has been reported in the literature regarding exploiting and controlling several distortion products generated by MSs at ...


Evaluation Of Bus-Bicycle And Bus/Right-Turn Traffic Delays And Conflicts, Katherine L. Keeling, Travis B. Glick, Miles Crumley, Miguel A. Figliozzi Jun 2019

Evaluation Of Bus-Bicycle And Bus/Right-Turn Traffic Delays And Conflicts, Katherine L. Keeling, Travis B. Glick, Miles Crumley, Miguel A. Figliozzi

Electrical and Computer Engineering Faculty Publications and Presentations

This research evaluates conflicts and delays caused by interactions among buses, bicycles, and right-turning vehicles at a mixed traffic corridor in Portland, OR. The study site has a near-side bus stop and a right curbside lane designated for buses and right-turning vehicles. Next to the bus/right-turn lane is a bicycle lane with a bicycle box ahead of the bus stop (i.e., between the intersection and the bus stop). This research examines two concerns caused by these overlapping bus, bicycle, and automobile facilities; the first is the number of bus-bicycle conflicts (as a proxy for safety) and the second ...


Electromagnetic Analysis Of A Wind Turbine Magnetic Gearbox, Kang Li, Sina Modaresahmadi, Wesley B. Williams, Jonathan Bird Jun 2019

Electromagnetic Analysis Of A Wind Turbine Magnetic Gearbox, Kang Li, Sina Modaresahmadi, Wesley B. Williams, Jonathan Bird

Electrical and Computer Engineering Faculty Publications and Presentations

The design of the second stage of a 59:1 multi-stage magnetic gearbox for a wind turbine demonstrator is presented. The multi-stage series-connected magnetic gearbox is composed of a 6.45 first stage and 9.14 second stage. A flux-focusing spoke-type rotor typology is used with a unique segmented fully laminated design. The impact of structural design changes is considered with respect to torque density. A new rotor typology is presented that enables the magnetic gearbox to be mechanically assembled first without magnets.


Very High Frequency Bipolar Junction Transistor Frequency Multiplier Drive Network Design And Analysis, Daniel Dale Schaeffer May 2019

Very High Frequency Bipolar Junction Transistor Frequency Multiplier Drive Network Design And Analysis, Daniel Dale Schaeffer

Dissertations and Theses

The function of a frequency multiplier is verbatim -- a frequency multiplier is a circuit that takes a signal of particular frequency at the input and produces harmonic multiples of the input signal's frequency at the output. Their use is widespread throughout history, primarily in the application of frequency synthesis. When implemented as a part of a large system, a chain of multipliers can be used to synthesize multiple reference signals from a single high-performance reference oscillator.

Frequency multiplier designs use a variety of nonlinear devices and topologies to achieve excitation of harmonics. This thesis will focus on the design ...


An Assessment Of The Decision Making Units’ Efficiency In Service Systems (The Case Of Cellular Telecom), Maoloud Dabab, Timothy R. Anderson May 2019

An Assessment Of The Decision Making Units’ Efficiency In Service Systems (The Case Of Cellular Telecom), Maoloud Dabab, Timothy R. Anderson

Student Research Symposium

Most tools and models on performance and quality of service management are generic and do not solve the complex technical systems, which the most critical component on the network and where these tools should be applied. The objective of this research is to assess the cellular performance and Base Transceiver Station (BTS) efficiency by proposing a robust model that is derived from multiple Key Performance Indicators (KPIs) based on technical and financial aspects. The novelty of this research provides a comprehensive multidimensional model for tuning the BTS parameters, which can lead to developing a standard global mobile network KPI. The ...


Explanation Methods For Neural Networks, Jack H. Chen, Christof Teuscher May 2019

Explanation Methods For Neural Networks, Jack H. Chen, Christof Teuscher

Student Research Symposium

Neural Networks (NNs) have become a basis of almost all state-of-the-art machine learning algorithms and classifiers. While NNs have been shown to generalize well to real-world examples, researchers have struggled to show why they work on an intuitive level. We designed several methods to explain the decisions of two state-of-the-art NN classifiers, ResNet and an All-CNN, in the context of the Japanese Society of Radiological Technology (JSRT) lung nodule dataset and the CIFAR-10 image dataset. Leading explanation methods LIME and Grad-CAM generate variations of heat maps which represent the regions of the input determined salient by the NN. We analyze ...


Reliable Explanations Via Adversarial Examples On Robust Networks, Walt Woods, Jack H. Chen, Christof Teuscher May 2019

Reliable Explanations Via Adversarial Examples On Robust Networks, Walt Woods, Jack H. Chen, Christof Teuscher

Student Research Symposium

Neural Networks (NNs) are increasingly used as the basis of advanced machine learning techniques in sensitive fields such as autonomous vehicles and medical imaging. However, NNs have been found vulnerable to a class of imperceptible attacks, called adversarial examples, which arbitrarily alter the output of the network. To close the schism between needing reliability in real-world applications and the fragility of NNs, we propose a new method for stabilizing networks, and show that as an added bonus, our technique results in reliable, high-fidelity explanations for the NN's decision. Compared to the state-of-the-art, this technique increased the area under the ...


Design And Performance Evaluation Of Linear And Axial-Flux Magnetic Gears, Mojtaba Bahrami Kouhshahi Apr 2019

Design And Performance Evaluation Of Linear And Axial-Flux Magnetic Gears, Mojtaba Bahrami Kouhshahi

Dissertations and Theses

The conversion from low speed to high speed and vice versa in various forms, including rotary and linear motion, is a requirement for a wide range of applications. For example, wind power generation requires a conversion of low speed rotation of turbine blades to high speed generator rotation, and ocean wave power generation is achievable by conversion of low speed linear motion to either high speed rotation or high speed linear motion. Mechanical gearboxes, hydraulic and pneumatic actuators are commonly used to achieve these conversions. However, these systems suffer from reliability issues, high maintenance requirements, noise, and lack of overload ...


Investigation Of Electronic And Optical Properties Of 2-Dimensional Semiconductor Tin Selenide (Snse) Thin Films, Shakila Afrin Mar 2019

Investigation Of Electronic And Optical Properties Of 2-Dimensional Semiconductor Tin Selenide (Snse) Thin Films, Shakila Afrin

Dissertations and Theses

Over the last 5 decades, the semiconductor industry has been well served by Si based technology due to its abundant availability, lower manufacturing cost, large wafer sizes and less complexity in fabrication. Over this period, electronic devices and integrated systems have been miniaturized by downscaling of the transistors. The miniaturization has been guided by the Moore's law where the numbers of transistors have doubled over every two years. However, the trend of transistor miniaturization is fast approaching its limit. Hence, alternate and innovative solutions are necessary to tackle this problem and this propels the research for finding novel materials ...


Efficient Methods For Robust Circuit Design And Performance Optimization For Carbon Nanotube Field Effect Transistors, Muhammad Ali Mar 2019

Efficient Methods For Robust Circuit Design And Performance Optimization For Carbon Nanotube Field Effect Transistors, Muhammad Ali

Dissertations and Theses

Carbon nanotube field-effect transistors (CNFETs) are considered to be promising candidate beyond the conventional CMOSFET due to their higher current drive capability, ballistic transport, lesser power delay product and higher thermal stability. CNFETs show great potential to build digital systems on advanced technology nodes with big benefits in terms of power, performance and area (PPA). Hence, there is a great need to develop proven models and CAD tools for performance evaluation of CNFET-based circuits. CNFETs specific parameters, such as number of tubes, pitch (spacing between the tubes) and diameter of CNTs determine current driving capability, speed, power consumption and area ...


Challenges In Designing A Mentorship Program For Electrical Engineering Freshmen, Branimir Pejcinovic, Melinda Holtzman Mar 2019

Challenges In Designing A Mentorship Program For Electrical Engineering Freshmen, Branimir Pejcinovic, Melinda Holtzman

Electrical and Computer Engineering Faculty Publications and Presentations

This Work in Progress Innovative Practice Paper addresses three challenges we face when teaching freshmen: a) how to present a wide variety of sub-fields in electrical engineering, b) how to establish the relevance of electrical engineering to things they care about, and c) how to relate electrical engineering to students' experiences. We are attempting to address these through a mentorship program involving recent alumni working with teams of freshman electrical engineering students. Mentors are expected to: (i) come to class and speak about their job experience, (ii) meet with their teams early in the term to help them get started ...


Spectral Clustering For Electrical Phase Identification Using Advanced Metering Infrastructure Voltage Time Series, Logan Blakely Jan 2019

Spectral Clustering For Electrical Phase Identification Using Advanced Metering Infrastructure Voltage Time Series, Logan Blakely

Dissertations and Theses

The increasing demand for and prevalence of distributed energy resources (DER) such as solar power, electric vehicles, and energy storage, present a unique set of challenges for integration into a legacy power grid, and accurate models of the low-voltage distribution systems are critical for accurate simulations of DER. Accurate labeling of the phase connections for each customer in a utility model is one area of grid topology that is known to have errors and has implications for the safety, efficiency, and hosting capacity of a distribution system. This research presents a methodology for the phase identification of customers solely using ...


Application Of Improved Feature Selection Algorithm In Svm Based Market Trend Prediction Model, Qi Li Jan 2019

Application Of Improved Feature Selection Algorithm In Svm Based Market Trend Prediction Model, Qi Li

Dissertations and Theses

In this study, a Prediction Accuracy Based Hill Climbing Feature Selection Algorithm (AHCFS) is created and compared with an Error Rate Based Sequential Feature Selection Algorithm (ERFS) which is an existing Matlab algorithm. The goal of the study is to create a new piece of an algorithm that has potential to outperform the existing Matlab sequential feature selection algorithm in predicting the movement of S&P 500 (^GSPC) prices under certain circumstances. The two algorithms are tested based on historical data of ^GSPC, and Support Vector Machine (SVM) is employed by both as the classifier. A prediction without feature selection ...


Aggregation Of Residential Water Heaters For Peak Shifting And Frequency Response Services, Thomas Leighton Clarke, Tylor Slay, Robert B. Bass, Conrad Eustis Jan 2019

Aggregation Of Residential Water Heaters For Peak Shifting And Frequency Response Services, Thomas Leighton Clarke, Tylor Slay, Robert B. Bass, Conrad Eustis

Electrical and Computer Engineering Faculty Publications and Presentations

The increased penetration of renewable energy resources poses challenges for grid stability. The stochastic generation of solar and wind power cannot be controlled to follow load. And, the transition away from synchronous generators is reducing the capacity to arrest and recover from frequency disturbances. Smart electric water heaters provide utilities with an appliance that can be remotely controlled and serve as a form of energy storage. They have very fast response times and make up a large amount of residential energy consumption, making them useful for load peak shifting as well as other ancillary grid services. As smart appliances become ...


Using Homing, Synchronizing And Distinguishing Input Sequences For The Analysis Of Reversible Finite State Machines, Martin Lukac, Michitaka Kameyama, Marek A. Perkowski, Pawel Kerntopf Jan 2019

Using Homing, Synchronizing And Distinguishing Input Sequences For The Analysis Of Reversible Finite State Machines, Martin Lukac, Michitaka Kameyama, Marek A. Perkowski, Pawel Kerntopf

Electrical and Computer Engineering Faculty Publications and Presentations

A digital device is called reversible if it realizes a reversible mapping, i.e., the one for which there exist a unique inverse. The field of reversible computing is devoted to studying all aspects of using and designing reversible devices. During last 15 years this field has been developing very intensively due to its applications in quantum computing, nanotechnology and reducing power consumption of digital devices. We present an analysis of the Reversible Finite State Machines (RFSM) with respect to three well known sequences used in the testability analysis of the classical Finite State Machines (FSM). The homing, distinguishing and ...