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Portland State University

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Full-Text Articles in Engineering

Approximate Pattern Matching Using Hierarchical Graph Construction And Sparse Distributed Representation, Aakanksha Mathuria Sep 2020

Approximate Pattern Matching Using Hierarchical Graph Construction And Sparse Distributed Representation, Aakanksha Mathuria

Dissertations and Theses

With recent developments in deep networks, there have been significant advances in visual object detection and recognition. However, some of these networks are still easily fooled/hacked and have shown "bag of features" kinds of failures. Some of this is due to the fact that even deep networks make only marginal use of the complex structure that exists in real-world images. Primate visual systems appear to capture the structure in images, but how?

In the research presented here, we are studying approaches for robust pattern matching using static, 2D Blocks World images based on graphical representations of the various components ...


Indoor Air Quality Impacts Of A Woodstove Exchange Program In Washington County, Oregon, Matthew Forrest Survilo Sep 2020

Indoor Air Quality Impacts Of A Woodstove Exchange Program In Washington County, Oregon, Matthew Forrest Survilo

Dissertations and Theses

More than six million people in the United States use wood stoves as their primary heat source. Wood stoves emit air pollutants that may impact health, e.g., wood combustion products are associated with premature death and aggravation of pulmonary and cardiovascular conditions. There are few studies investigating the efficacy of wood stove exchange programs (WSEPs) as a method to improve indoor air quality (IAQ). In partnership with Washington County Department of Health and Human Services we conducted an air quality study to measure the impact of a WSEP on indoor and neighborhood levels of wood combustion products. Twenty households ...


Empirical Analysis Of Cbow And Skip Gram Nlp Models, Tejas Menon Sep 2020

Empirical Analysis Of Cbow And Skip Gram Nlp Models, Tejas Menon

University Honors Theses

CBOW and Skip Gram are two NLP techniques to produce word embedding models that are accurate and performant. They were invented in the seminal paper by T. Mikolov et al. and have since observed optimizations such as negative sampling and subsampling. This paper implements a fully-optimized version of these models using Py-Torch and runs them through a toy sentiment/subject analysis. It is weakly observed that different corpus types affect the skew of work embeddings such that fictional corpus are better suited for sentiment analysis and non-fictional for subject analysis.


Comparing The Promise And Reality Of E-Scooters: A Critical Assessment Of Equity Improvements And Mode-Shift, Michael Glenn Mcqueen Sep 2020

Comparing The Promise And Reality Of E-Scooters: A Critical Assessment Of Equity Improvements And Mode-Shift, Michael Glenn Mcqueen

Dissertations and Theses

In just three years, e-scooters have substantially disrupted and altered the urban mobility landscape. Throughout this period, they have been commonly touted as part of a larger micromobility solution that promises to erase equity barriers and solve the first-mile/last-mile problem. However, few studies in the nascent e-scooter literature have considered these claims. In this study, we surveyed students at Portland State University (n = 1,968) about the role that e-scooters, among other modes, played in meeting their general and university-related travel needs. We then estimated models that incorporated demographics, travel behavior, and latent attitudes distilled using exploratory factor analysis ...


Theoretical And Experimental Validation Of A Cubesat's L-Band Communication System, Evangelos Mastrogiannis Sep 2020

Theoretical And Experimental Validation Of A Cubesat's L-Band Communication System, Evangelos Mastrogiannis

Dissertations and Theses

An L-band uplink communication system was designed and validated in the lab for a CubeSat satellite operating in low Earth orbit (LEO). This paper investigates communication link analysis, discusses the design strategy for an inexpensive CubeSat receiver operating in L-band with a moderate power Earth station transmitter, and validates the link budget with prototype hardware using an anechoic chamber.

A receiver's required carrier-to-noise ratio (CNR) establishes the basis for a link budget. The requirement for a digital communication link is set by the bit-error-rate (BER) requirement of a chosen communication protocol which is inversely related to the energy per ...


Synthesizing Expressive Behaviors For Humanoid Robots, Mathias Irwan Sunardi Jul 2020

Synthesizing Expressive Behaviors For Humanoid Robots, Mathias Irwan Sunardi

Dissertations and Theses

Humanoid robots are expected to be able to communicate with expressive gestures at the same level of proficiency as humans. However, creating expressive gestures for humanoid robots is difficult and time consuming due to the high number of degrees of freedom (DOF) and the iterations needed to get the desired expressiveness.

Current robot motion editing software has varying levels of sophistication of motion editing tools ranging from basic ones that are text-only, to ones that provide graphical user interfaces (GUIs) which incorporate advanced features, such as curve editors and inverse kinematics. These tools enable users to create simple motions; but ...


Determinants Of Student Information Technology Adoption, Hans P. Vanderschaaf Jul 2020

Determinants Of Student Information Technology Adoption, Hans P. Vanderschaaf

Dissertations and Theses

Innovating service delivery in higher education is central to supporting institutional and societal goals of increasing the numbers of college graduates and for transforming higher education institutions to center on the needs of today's students. Within this context, technology plays a critical role. This research seeks to contribute to institutional, academic and educational technology sector efforts to dramatically enhance service quality, in support of improving undergraduate student outcomes (student success), by identifying the determinants of student information technology adoption and removing barriers to accessing higher education.

Using a mixed-methods and empirical approach based on the Unified Theory of Acceptance ...


Dynamic Effects Of Inertial Particles On The Wake Recovery Of A Model Wind Turbine, Sarah E. Smith Jul 2020

Dynamic Effects Of Inertial Particles On The Wake Recovery Of A Model Wind Turbine, Sarah E. Smith

Dissertations and Theses

Impacting particles such as rain, dust, and other debris can have devastating structural effects on wind turbines, but little is known about the interaction of such debris within turbine wakes. This study aims to characterize behavior of inertial particles within the turbulent wake of a wind turbine and relative effects on wake recovery. Here a model wind turbine is subjected to varied two-phase inflow conditions, with wind as the carrier fluid (Re[lambda]=49-88) and polydisperse water droplets (26 to 45µ m in diameter) at varied concentrations (Φv=0.24 x 10-5 - 1.3 x 10-5), comparing ...


Exploring Policies And Strategies For The Diffusion Of Remote Patient Monitoring (Rpm) For The Care Of Senior Population, Hamad Asri Alanazi Jul 2020

Exploring Policies And Strategies For The Diffusion Of Remote Patient Monitoring (Rpm) For The Care Of Senior Population, Hamad Asri Alanazi

Dissertations and Theses

Telemedicine offers great promise in addressing some of the healthcare challenges such as the increase of healthcare expenditure, a growing population, and a projected physician shortage; telemedicine is increasingly being included in the discussion of medicine's future. Telemedicine offers the capabilities to deliver healthcare across distances at reduced costs while maintaining or even increasing the quality of treatment and services.

The objective of this research is to develop a model to evaluate alternative solutions to increase the adoption of RPM for the senior population. Also, the research provides a systematic approach for a comprehensive assessment of teleconsultation adoption, develop ...


Droplet Ejections During Wet Lab Operations Aboard Spacecraft, Caleb Cushman Turner Jul 2020

Droplet Ejections During Wet Lab Operations Aboard Spacecraft, Caleb Cushman Turner

Dissertations and Theses

The breakup and rupture of liquid bridges, thin films, bubbles, droplets, rivulets, and jets can produce satellite droplets that are subsequently ejected into their surrounding environment. For example, when any solid object is withdrawn from a liquid bath, the formation of an ever-thinning columnar liquid bridge eventually ruptures along the axis of the bridge. When rupture occurs under typical pipetting conditions the dynamics governing the rupture almost always produce at a minimum a satellite droplet. When these droplets occur they are often too small and too fast to be observed by the human eye. In a terrestrial environment they are ...


Evaluating R&D Projects In Regulated Utilities: The Case Of Power Transmission Utilities, Edwin Garces Jul 2020

Evaluating R&D Projects In Regulated Utilities: The Case Of Power Transmission Utilities, Edwin Garces

Dissertations and Theses

R&D project selection is essential for many organizations; however, it is a complex decision since it is affected by many factors. These factors vary among organizations because of their different objectives and conditions. There are limited budgets for the investments, and the current R&D project selection methods are focused on financial analysis or complex mathematical probabilistic calculations. Therefore, the main motivation of this research is to create a method to help improve the ex-ante selection of R&D projects in regulated organizations. More importantly, the case application is the electric transmission utilities sector, which plays one of the most critical roles in the entire electric power ...


A Market Diffusion Potential (Mdp) Assessment Model For Residential Energy Efficient (Ee) Technologies In The U.S., Momtaj Khanam Jul 2020

A Market Diffusion Potential (Mdp) Assessment Model For Residential Energy Efficient (Ee) Technologies In The U.S., Momtaj Khanam

Dissertations and Theses

The Diffusion of Residential Energy Efficient (EE) Technologies has been studied for many years. Finding ways to bridge the energy efficiency gap and increase the diffusion of these technologies have been of much interest to researchers and practitioners alike. However, in most studies, diffusion is equated to adoption of EE technologies by consumers. The present study tries to break this mindset and develops a model to assess the diffusion of residential EE technologies from the market's perspective. The model assesses diffusion of an EE technology based on the market's ability to provide benefits to customers that are identified ...


Ultrasonic Coda Wave Comparison For Quality Control Of Manufactured Parts: Proof Of Feasibility, Alexei Marin-Cortes Jul 2020

Ultrasonic Coda Wave Comparison For Quality Control Of Manufactured Parts: Proof Of Feasibility, Alexei Marin-Cortes

Civil and Environmental Engineering Master's Project Reports

Manufactured parts are a staple of modern urban life, visible in homes (e.g., kitchen appliances), offices (e.g., printers), the automobile and aerospace industries (e.g., body parts), and more. This M.S. project intended to determine whether ultrasonic testing could be used in a simple and rapid manner to perform quality control of manufactured parts. Ultrasonic testing is employed for this purpose using two surface-coupled transducers, one being a transmitter and the other one a receiver. An ultrasonic pulse, which is generated by the transmitting transducer, propagates through the part, collecting information about material and geometry, as well ...


Ce-Qual-W2 Hydrodynamic And Water Quality Model Of The Cedar River Municipal Watershed, Amory Spencer Cervarich Jul 2020

Ce-Qual-W2 Hydrodynamic And Water Quality Model Of The Cedar River Municipal Watershed, Amory Spencer Cervarich

Dissertations and Theses

The laterally averaged, two-dimensional model CE-QUAL-W2 was used to develop a water quality model of the Cedar River Municipal Watershed as a reservoir management and climate change scenario tool. The 90,638-acre watershed, located 56 kilometers southeast of Seattle, WA, provides drinking water to over 1.4 million people. The watershed relies on two waterbodies for storage, Chester Morse Lake and the Masonry Pool. The Masonry Dam is the main storage structure in the watershed. The Cedar River flows downstream from the Masonry Dam for 57 kilometers to Lake Washington. The reservoir model simulated Chester Morse Lake and the Masonry ...


An Assessment Of The Decision-Making Units' Efficiency In Service Systems, Maoloud Yakhlif Dabab Jun 2020

An Assessment Of The Decision-Making Units' Efficiency In Service Systems, Maoloud Yakhlif Dabab

Dissertations and Theses

Most tools and models of performance and quality of service management are generic and do not solve complex technical systems. The critical components of the system need such tools to assess their efficiency to make a better decision about them. One of the primary objectives in the service systems is to improve the ability of efficiency, effectiveness, and sustainability of critical assets. One of the challenges with improving critical assets is the amount of major capital spending needed to upgrade a technology infrastructure with a high obsolescence rate. This along with usage and reliability issues, makes evaluating mobile cells to ...


Design Of A 7-Mhz Portable Direct Conversion Transceiver With Digitally Controlled Keying, Abram Morphew Jun 2020

Design Of A 7-Mhz Portable Direct Conversion Transceiver With Digitally Controlled Keying, Abram Morphew

Dissertations and Theses

This thesis outlines the design of a portable direct conversion transceiver system for the 7-MHz (or 40m) band. This band is popular due to its propagation characteristics which allow for world-wide communication with very low power. The transceiver utilizes a crystal-stabilized local oscillator optimized for frequency agility, low power consumption, and an optimal drive level of +7 dBm. A low power 8-bit microcontroller acts as an interface for either a straight key providing manual Morse code operation or digital logic control from a personal computer. It also acts as a side tone oscillator providing audio feedback to the operator during ...


Designing Gates And Architectures For Superconducting Quantum Systems, Sahar Daraeizadeh Jun 2020

Designing Gates And Architectures For Superconducting Quantum Systems, Sahar Daraeizadeh

Dissertations and Theses

Large-scale quantum computers can solve certain problems that are not tractable by currently available classical computational resources. The building blocks of quantum computers are qubits. Among many different physical realizations for qubits, superconducting qubits are one of the promising candidates to realize gate model quantum computers. In this dissertation, we present new multi-qubit gates for nearest-neighbor superconducting quantum systems. In the absence of a physical hardware, we simulate the dynamics of the quantum system and use the simulated environment as a framework for test, design, and optimization of quantum gates and architectures. We explore three different simulation-based gate design methodologies ...


Facilitating Mixed Self-Timed Circuits, Alexandra R. Hanson May 2020

Facilitating Mixed Self-Timed Circuits, Alexandra R. Hanson

University Honors Theses

Designers constrain the ordering of computation events in self-timed circuits to ensure the correct behavior of the circuits. Different circuit families utilize different constraints that, when families are combined, may be more difficult to guarantee in combination without inserting delay to postpone necessary events. By analyzing established constraints of different circuit families like Click and GasP, we are able to identify the small changes necessary to either 1) avoid constraints entirely; or 2) decrease the likelihood of necessary delay insertion. Because delay insertion can be tricky for novice designers and because the likelihood of its requirement increases when mixing different ...


Chehalis River And Tributary Water Quality And Hydrodynamic Modeling: Model Setup, Calibration Analysis For 2013-2015, Tel Jensen Apr 2020

Chehalis River And Tributary Water Quality And Hydrodynamic Modeling: Model Setup, Calibration Analysis For 2013-2015, Tel Jensen

Dissertations and Theses

The Chehalis River is located in southwest Washington State. Its headwaters are in the Willapa Hills, and it drains parts of the Doty Hills, the western foothills of the Cascade Mountains, and the southern Olympic Mountains. The Chehalis River is over 125 miles long and its basin is over 2000 square miles spanning parts of seven counties and diverse land uses.

CE-QUAL-W2 is a widely used two-dimensional (vertical and longitudinal) hydrodynamic and water quality model developed by the US Army Corp of Engineers and the Water Quality Research Group at Portland State University. Version 4.2 includes the ability to ...


A Numerical Investigation Of Microgravity Evaporation, Daniel Peter Ringle Apr 2020

A Numerical Investigation Of Microgravity Evaporation, Daniel Peter Ringle

Dissertations and Theses

Evaporation is important to myriad engineering processes such as cooling, distillation, thin film deposition, and others. In fact, NASA has renewed interest in using cabin air pressure evaporation as a means to recycle waste water in space. As one example, NASA recently conducted experiments aboard the International Space Station (ISS) to measure evaporation rates in microgravity and to determine the impacts of porous structure on the process. It has long been assumed that differences in evaporation rates between 1-g0 and microgravity are small. However, discrepancies by as much as 40% have been observed in practice. The assumption now ...


Absorptive Reflectionless Filters, Guy Barry Lemire Mar 2020

Absorptive Reflectionless Filters, Guy Barry Lemire

Dissertations and Theses

For many applications requiring some sort of signal filtering or signal conditioning, the filter requirements are usually approached with a single purpose in mind, which is to maximize both passband signal amplitude and stop band signal attenuation to the load with little to no thought given to what happens to the stop band signal energy. Many conventional filters have very poor impedance matching in the stopband resulting in reflected energy or large return loss (S11). This reflected energy can then cause interactions with adjoining system components which do not in general respond well to spurious reflected energy and can ...


Narrowing The Cognitive Distance Between Engineers And Customers: A Novel Approach, Based On Fuzzy Cognitive Mapping, Byung Sung Yoon Feb 2020

Narrowing The Cognitive Distance Between Engineers And Customers: A Novel Approach, Based On Fuzzy Cognitive Mapping, Byung Sung Yoon

Dissertations and Theses

During concept development, product developers consider product users and their future experience, cost, development and manufacturing efficiency, product function/quality, and differentiation of the product in the market. Development teams often struggle to adequately address all of these considerations, due to the following reasons: (1) Differences in technological and experiential knowledge, methods used, and communication styles that make it difficult for customers/user, marketing, and engineering to communicate effectively. As a result, important factors may not be sufficiently considered. (2) Product design factors, including technological alternatives, functions, features, benefits, and customer value are interdependent: in some cases, customers are willing ...


Classifying Seabed Parameters From Normal Incidence Reflections: Model Comparison And Inversion Technique, Megan Frantz Jan 2020

Classifying Seabed Parameters From Normal Incidence Reflections: Model Comparison And Inversion Technique, Megan Frantz

Dissertations and Theses

As of the year 2019, only about five percent of the seafloor has been topologically mapped and classified for type (e.g., sand, silt, gravel). To rapidly survey the seabed from surface ships or underwater vehicles, acoustic remote sensing methods are needed. In this thesis, acoustic measurements and inverse modeling is investigated as a way to classify seabed type based on estimating parameters such as density, sound speed, and interface roughness. The method uses normal incident acoustic measurements that can be made using either a single beam echo sounder or the normal incident beams from a side scan sonar. The ...


Robust Maximum Flow Network Interdiction Problem, Darshan Rajesh Chauhan Jan 2020

Robust Maximum Flow Network Interdiction Problem, Darshan Rajesh Chauhan

Dissertations and Theses

In this thesis, a maximum flow-based network interdiction problem considering uncertainties in arc capacities and interdiction resource consumption is solved. The problem consists of two entities with opposing objectives: the goal of the adversary is to maximize the flow of illicit drugs through the network, while the goal of the interdictor is to minimize the maximum flow by completely interdicting arcs given a specified amount of resources. Lack of complete information about the usage patterns of the transportation network by the adversary results in an uncertain estimate of arc capacity and resources required for interdiction by the interdictor. To account ...


Evaluation Of A Novel Remote Displacement Sensor Prototype Using Video And Laser-Based Technology For Civil Infrastructure Applications, Nicholas J. Brown Dec 2019

Evaluation Of A Novel Remote Displacement Sensor Prototype Using Video And Laser-Based Technology For Civil Infrastructure Applications, Nicholas J. Brown

Civil and Environmental Engineering Master's Project Reports

Deflection measurements on structures, especially with regards to long-term monitoring, continues to be a challenge with current sensor technologies. Material degradation and changes in the mechanical properties due to aging (for example, creep and shrinkage in concrete bridges) directly impact the deflections exhibited by a structure. In this article we introduce and discuss the evaluation of a novel laser and video-based displacement sensor prototype to monitor displacements and rotations in structures remotely. The sensor is both inexpensive, using off-the shelf components, but also accurate and practical for situations that do not allow the use of conventional displacement sensors, which require ...


Flood Dynamics In The Portland Metropolitan Area, Past, Present, And Future, Lumas Terence Helaire Dec 2019

Flood Dynamics In The Portland Metropolitan Area, Past, Present, And Future, Lumas Terence Helaire

Dissertations and Theses

The Portland area has an extensive flood history since it was founded in 1845. In the late 19th century, the Portland area was prone to flooding from snowmelt freshets (3-6 months duration) and brief winter rain or rain-on-snow events. Since that time the magnitude of spring freshets has been curtailed by 45% due to climate change, flow diversions, and reservoir management. Along with changes in hydrology, the bathymetry of the Lower Columbia River has been altered by the dredging of the navigation channel, diking, and land reclamation. To understand how these changes in hydrology and bathymetry have affected tidal and ...


Impact Of Titanium Dioxide Nanoparticles On Nutrient And Contaminant Reduction In Wastewater Treatment Wetlands, Madeline J. Hubbard Dec 2019

Impact Of Titanium Dioxide Nanoparticles On Nutrient And Contaminant Reduction In Wastewater Treatment Wetlands, Madeline J. Hubbard

Civil and Environmental Engineering Master's Project Reports

Metallic nanoparticles are found in a variety of commercial products and industrial processes, and have become more common in the last few decades. As nanoparticles are toxic to biota and have the potential to spread other types of contamination, their increased use has become a concern. Research into the transport of nanoparticles in subsurface and surface waters shows a wide range in mobility, but that they are most likely to collect in systems with low linear velocities and high organic content. As a result, wetlands are the most vulnerable to nanoparticle contamination. Wetlands receiving and treating wastewater effluent have an ...


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 ...


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 ...