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Portland State University

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Dissertations and Theses

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Relationships Between In-Situ Tests And Soil Cyclic Strength For Earthquake Hazard Characterization In The Pacific Northwest, Tanner Scott Bryantt Dec 2020

Relationships Between In-Situ Tests And Soil Cyclic Strength For Earthquake Hazard Characterization In The Pacific Northwest, Tanner Scott Bryantt

Dissertations and Theses

Strong earthquake shaking is a natural hazard threat in the Pacific Northwest. Soil failure due to strong earthquake shaking -- known as cyclic soil failure or liquefaction -- is expected to cause large ground deformations and damage to roads, bridges, and other civil infrastructure. Cyclic soil strength (CRR) is often characterized with in-situ geotechnical tests including the cone penetration test (CPT). Relationships between CRR and in-situ test data are not well established for soils in the Pacific Northwest. Portland State University, in partnership with New Albion Geotechnical has compiled a database of cyclic lab tests for Pacific Northwest soils to characterize the ...


Achieving High Reliability Organizations Using Fuzzy Cognitive Maps - The Case Of Offshore Oil And Gas, Ahmed A. Alibage Dec 2020

Achieving High Reliability Organizations Using Fuzzy Cognitive Maps - The Case Of Offshore Oil And Gas, Ahmed A. Alibage

Dissertations and Theses

The safety culture of so-called high-reliability organizations (HROs) encompasses values, routines, and work processes that allow an organization to prevent mistakes and quickly bounce back if unexpected events occur. It is said to provide a model for improving organizational resilience in the offshore oil and gas industry, where small errors can grow into accidents with devastating environmental, social, and economic impacts. To date, such a transfer of successful practices is impeded by a lack of system perspective that would allow researchers and practitioners to fully understand the safety dynamics in HROs, adjust them to the unique setting of offshore oil ...


Entrainment Processes For A Jet In Cross-Flow: The Quantification Of Turbulent Contributions And Their Importance On Accurate Modeling, Graham Asher Freedland Dec 2020

Entrainment Processes For A Jet In Cross-Flow: The Quantification Of Turbulent Contributions And Their Importance On Accurate Modeling, Graham Asher Freedland

Dissertations and Theses

A jet in cross flow (JICF) is examined experimentally by injecting a stream of air into crossing fluid with an aim into quantifying entrainment process and downstream evolution. The behavior of JICF is important to fields ranging from turbine-blade cooling to smokestack pollution and volcanic eruption dynamics. Existing simplified volcanic plume models are tested; most importantly, the near-field contributions of complex interconnected vortex systems, which present significant uncertainties because they assume negligible turbulence. While jets in irrotational cross-flow have been investigated, this analysis has focused on the interaction between a turbulent jet in low and highly turbulent cross-flow created by ...


Methodologies To Quantify Transit Performance Metrics At The System-Level Using High-Resolution Gps, Stop-Level, And Gtfs Archived Transit Data, Travis Bradley Glick Nov 2020

Methodologies To Quantify Transit Performance Metrics At The System-Level Using High-Resolution Gps, Stop-Level, And Gtfs Archived Transit Data, Travis Bradley Glick

Dissertations and Theses

Performance metrics have typically focused at two main scales: a microscopic scale that focuses on specific locations, time-periods, and trips; and, a macroscopic scale that averages metrics over longer times, entire routes, and networks. When applied to entire transit systems, microscopic methodologies often have computational limitations while macroscopic methodologies ascribe artificial uniformity to non-uniform analysis areas. These limitations highlight the need for a middle approach. This dissertation presents a mesoscopic analysis based around timepoint-segments, which are a novel application of an existing system for many transit agencies. In the United States, fix-route transit is typically defined by a small subset ...


Determinants Of Green Purchase Intentions Of Saudi Consumers, Amani Mohammed Kaadoor Oct 2020

Determinants Of Green Purchase Intentions Of Saudi Consumers, Amani Mohammed Kaadoor

Dissertations and Theses

Much of the research on how and why consumers engage in pro-environmental consumption has occurred in the wealthy countries of the West, where green markets are increasingly well established. Research in other economic and cultural context is sparse and points to large regional differences that cause some researchers to call key theoretical foundations, such as the Theory of Planned Behavior, into question. In response, this study investigates the factors that predict green purchase intention for food and personal care products in Saudi Arabia, a wealthy country with a rapidly growing population, severe environmental challenges, and a nascent green consumer market ...


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 ...


Analog Statistical Design For Manufacturability, Yu-Shan Wang Sep 2020

Analog Statistical Design For Manufacturability, Yu-Shan Wang

Dissertations and Theses

The manufacturing yield, overkill, and defect level limit the feasibility of analog circuits in SoCs. The conventional method of handling process and environmental variation is to assign a design margin such that the design meets specifications at several processes and environmental corners. However, checking only extreme corners limits performance in comparison to the more rigorous statistical approach of the computing manufacturing and quality figure of merit. The statistical approach requires transistor-level simulation of hundreds or even thousands of samples, not just a few corners, and thus is very time consuming.

This research offers a method for reducing the time required ...


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 ...


A Scoring Model To Evaluate Offshore Oil Projects: Case Of Eni And Mellitah Oil & Gas, Abdulhakim Giadedi Sep 2020

A Scoring Model To Evaluate Offshore Oil Projects: Case Of Eni And Mellitah Oil & Gas, Abdulhakim Giadedi

Dissertations and Theses

Offshore oil projects have many different and unique characteristics, such as larger project size, higher number of scopes, and higher complexity. In fact, offshore oil projects described as mega projects are ones that require significant assessment and acquisition methods in order to reduce risks and failures. Traditionally, cash flow analysis and return on investment are the most known factors to evaluate offshore oil projects. However, there are several other internal and external factors that affect the overall performance of offshore oil projects. A comprehensive approach and advanced tools are required to evaluate these factors that can have a significant impact ...


Synthesis And Assessment Of Radiotherapy-Enhancing Nanoparticles, Hayden Winter Aug 2020

Synthesis And Assessment Of Radiotherapy-Enhancing Nanoparticles, Hayden Winter

Dissertations and Theses

Radiation Therapy (RT) is a common treatment for cancerous lesions that acts by ionizing matter in the affected tissue, causing cell death. The disadvantage of RT is that it is most often delivered via an external beam of radiation which must pass through healthy tissues to reach the target site, ionizing matter within healthy tissues as well. To address this drawback, techniques are being developed for increasing RT-induced cell death in a target tissue while minimizing cell death in surrounding tissues. This effect is known as radiation dose enhancement or RT enhancement.

The approach to RT enhancement studied in this ...


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 (Reλ = 49 - 88) and polydisperse water droplets (26 to 45µm in diameter) at varied concentrations (Φv=0.24 x 10-5 - 1.3 x 10 ...


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 ...


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 ...


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 ...


Optimal Boundary Detection Using Autonomous Mobile Sensors, Phillip Justin Kearns Jan 2020

Optimal Boundary Detection Using Autonomous Mobile Sensors, Phillip Justin Kearns

Dissertations and Theses

A fundamental challenge to modern science and engineering is the ability to rapidly and accurately determine the spatial extent of environmental phenomena. In monitoring the spread of hazardous pollution, for example, all points with pollutant concentration above or below a fixed threshold can be considered as two classes in a binary classification problem. In this instance, the goal is to accurately estimate the decision boundary as quickly as possible. To generate models and predictions, scientists must choose their sampling locations from a vast array of possibilities. This thesis develops a policy for determining the optimal sample locations for a fixed ...


The Optimization Of Machining Parameters For Milling Operations By Using The Nelder Mead Simplex Method, Yubin Lee Jan 2020

The Optimization Of Machining Parameters For Milling Operations By Using The Nelder Mead Simplex Method, Yubin Lee

Dissertations and Theses

Machining operations need to be optimized to maximize profit for computer numerical control (CNC) machines. Although minimum production time could mean high productivity, it can not guarantee maximum profit rate in CNC milling operations. The possible range of machining parameters is limited by several constraints, such as maximum machine power, surface finish requirements, and maximum cutting force for the stability of milling operations. Among CNC machining parameters, cutting speed and feed have the greatest effect on machining operations. Therefore, cutting speed and feed are considered as main process variables to maximize the profit rate of CNC milling operations.

A variety ...


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 ...