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Portland State University

Dissertations and Theses

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Full-Text Articles in Engineering

A Method For Comparative Analysis Of Trusted Execution Environments, Stephano Cetola Jun 2021

A Method For Comparative Analysis Of Trusted Execution Environments, Stephano Cetola

Dissertations and Theses

The problem of secure remote computation has become a serious concern of hardware manufacturers and software developers alike. Trusted Execution Environments (TEEs) are a solution to the problem of secure remote computation in applications ranging from "chip and pin" financial transactions to intellectual property protection in modern gaming systems. While extensive literature has been published about many of these technologies, there exists no current model for comparing TEEs. This thesis provides hardware architects and designers with a set of tools for comparing TEEs. I do so by examining several properties of a TEE and comparing their implementations in several technologies ...


Incorporating Conditional ß-Mean Based Equity Metric In Coverage Based Facility Location Problems, Rohan Sirupa Jun 2021

Incorporating Conditional ß-Mean Based Equity Metric In Coverage Based Facility Location Problems, Rohan Sirupa

Dissertations and Theses

A classical maximum coverage facility location problem (MCLP) tries to maximize the coverage by serving all possible demands within the specified coverage radius. Depending on the applications, several families of MCLP variants have been developed - each with its unique set of additional constraints. One specific application is locating Emergency medical service (EMS) units. EMS units such as ambulances or drones with emergency supplies are located using models such as the maximum expected survival location problem (MEXSLP). However, a classical MEXSLP model tends to locate EMS units near densely populated regions, resulting in increased response times for lowly populated regions. If ...


Method Of Modeling The Swing Equation Using Time Synchronized Measurements, Robert Ferraro May 2021

Method Of Modeling The Swing Equation Using Time Synchronized Measurements, Robert Ferraro

Dissertations and Theses

In three phase, high-voltage transmission systems, synchronous generators accelerate or decelerate to adapt to changing power transfer requirements that occur during system disturbances. In network electrical power systems, frequency changes constantly based on system dynamics. Modeling network dynamics from oscillations and transients using time-synchronized measurements can provide real-time information, including angular displacements, voltage and current phasors, frequency changes, and rate of signal system decay from positive-sequence components. Power system voltage and current waveforms are not steady-state sinusoids, especially during system disturbances. These waveforms contain sustained harmonic and non-harmonic components. Additionally, because of faults and other switching electromagnetic transients, there may ...


Development Of A Design Guideline For Pile Foundations Subjected To Liquefaction-Induced Lateral Spreading, Milad Souri May 2021

Development Of A Design Guideline For Pile Foundations Subjected To Liquefaction-Induced Lateral Spreading, Milad Souri

Dissertations and Theses

Extensive loss of stiffness and strength in liquefied soils can cause large ground deformations during strong earthquake shaking. One of the major sources of damage in pile foundations in liquefied soil is the excessive deformation due to lateral spreading. Pile-supported wharves subjected to earthquake motions are expected to accommodate inertial loads imposed at pile head from the superstructure as well as the kinematic loads imposed on piles from the lateral ground deformations. Current design codes significantly vary on how to combine inertia and kinematic demands. Recent research on soil-foundation-structure interaction suffers from lack of experiment-based data. There is a serious ...


An Analysis Of Suspended Sediment Dynamics In A Partially Mixed Estuary, Riyadh Hamad Muttaleb Mar 2021

An Analysis Of Suspended Sediment Dynamics In A Partially Mixed Estuary, Riyadh Hamad Muttaleb

Dissertations and Theses

The purpose of this work is to investigate via data analysis and numerical modeling the SPM (suspended particulate matter) dynamics of a heavily contaminated partially urban estuary, the Lower Passaic River estuary (LPR), NJ. Accordingly, I investigate the quantity and mechanics of variation of fine and coarse SPM in the LPR via data analysis. Data analysis focuses on the parameters that affect SPM dynamics at six moored stations occupied during the Fall and Spring seasons, from near the estuary mouth to tidal freshwater. A 3D hydrodynamic model (Delft3D-FM) is used to analyze the effects of estuary topography on the dynamic ...


Memristor Crossbar Array Testing Using Sneak Paths, Rasika Dhananjay Joshi Mar 2021

Memristor Crossbar Array Testing Using Sneak Paths, Rasika Dhananjay Joshi

Dissertations and Theses

Moore's law decline has paved the way to shift to new technologies at architectural and device levels. CMOS based technologies are facing many challenges with the growing demand for miniaturization. The growing heat dissipation is the major limitation for performance, energy efficiency and reliability with the increasing transistor count in integrated circuits. Manufacturing costs and process/memory performance gap have also grown steadily over the last several decades with the scaling down of the CMOS feature size. Memristor, a nanoscale device, has the potential to address the CMOS limitations because of its non-volatility, high density, low power operation, low ...


Power Distribution System Tools For Analyzing Impacts Of Projected Electric Vehicle Load Growth Using Gridlab-D, Shahad Alomani Feb 2021

Power Distribution System Tools For Analyzing Impacts Of Projected Electric Vehicle Load Growth Using Gridlab-D, Shahad Alomani

Dissertations and Theses

The increased penetration of Electric Vehicle (EV) will provide substantial benefits to the environment. However, each EV will present a significant additional load to electric power distribution infrastructure, especially to radial distribution feeders. The additional load may cause transformers to operate beyond their thermal limits, unacceptable voltage drops along distribution lines, and primary conductor overloads. It is now, more than ever, vital to understand the limitations of existing infrastructure in light of an accelerating push for greener alternatives with insight that stems from modeling, simulation, and proper analysis as the backbone to a well-informed response.

The objective of this work ...


Automated Test Generation For Validating Systemc Designs, Bin Lin Jan 2021

Automated Test Generation For Validating Systemc Designs, Bin Lin

Dissertations and Theses

Modern system design involves integration of all components of a system on a single chip, namely System-on-a-Chip (SoC). The ever-increasing complexity of SoCs and rapidly decreasing time-to-market have pushed the design abstraction to the electronic system level (ESL), in order to increase design productivity. SystemC is a widely used ESL modeling language that plays a central role in modern SoCs design process. ESL SystemC designs usually serve as executable specifications for the subsequent SoCs design flow. Therefore, undetected bugs in ESL SystemC designs may propagate to low-level implementations or even final silicon products. In addition, modern SoCs design often involves ...


Methods For Object Tracking With Machine Vision, Zachary Simon Stamler Jan 2021

Methods For Object Tracking With Machine Vision, Zachary Simon Stamler

Dissertations and Theses

As machine learning and deep learning systems continue to find applications in science and engineering, the problem of providing these systems with high-quality data continues to increase in importance. Many of these systems utilize machine vision as their primary source of information, and in order to maximally leverage their abilities it is important to be able to provide them with high quality, accurate data. Unfortunately, many sets of tracking data extracted from video suffer from the problem of missing frames, which can arise from a multitude of causes depending on the system. These missing frames can result in confusion between ...


Mit-S1 Constitutive Model Calibration For A Portland-Area Soil, Steven Ryan Young Jan 2021

Mit-S1 Constitutive Model Calibration For A Portland-Area Soil, Steven Ryan Young

Dissertations and Theses

Soils that are intermediate to sands and clays are a challenge for geotechnical engineers since most methods for interpreting soil properties or soil behaviors are based on sands or clays and do not address behaviors of intermediate soils. This is a particular challenge for engineers in the Portland-area where many of the major soil units are composed of intermediate soils. Analysis of intermediate soils is further challenged since many standard constitutive models are based on sandy or clay-like soils. However, the MIT-S1 constitutive model is capable of capturing intermediate soil behavior. A calibration of the MIT-S1 constitutive model for Portland-area ...


Development Of Graphene Synthesis And Characterization Techniques Toward Cmos Applications And Beyond, Otto Kno Zietz Jan 2021

Development Of Graphene Synthesis And Characterization Techniques Toward Cmos Applications And Beyond, Otto Kno Zietz

Dissertations and Theses

Graphene exhibits mechanical and electrical properties which, coupled with its two dimensional (2D) morphology, make it an attractive material component for inclusion in a wide range of industries. Since the discovery of graphene in 2004, industry adoption has been limited due to the demanding synthesis requirements for high quality and connected graphene as well as the difficulties associated with direct incorporation. Chemical vapor deposition (CVD) has emerged as the most cost efficient method for producing high quality graphene at scales suitable for mass production. However, the 1000°C temperatures and micrometer thick catalysts required for this process preclude direct inclusion ...


Numerical Simulation Of Continuous Cone Penetration And Interpretation Of Cptu Dissipation Tests, Andrew Phillip Eugene Huffman Jan 2021

Numerical Simulation Of Continuous Cone Penetration And Interpretation Of Cptu Dissipation Tests, Andrew Phillip Eugene Huffman

Dissertations and Theses

The piezocone penetration test (CPTu) is a commonly used method of geotechnical site investigation. The CPTu is especially useful because it provides a nearly continuous data profile of in-situ soil behavior, which can be correlated to useful engineering parameters. However, limitations exist for interpretation of geotechnical properties from CPTu data and for numerical analysis of cone penetration problems. The research presented in this thesis examines interpretation of coefficient of consolidation from CPTu dissipation test data and implementation of an algorithm to advance numerical simulation of cone penetration problems. This thesis presents analysis of CPTu dissipation responses from field-measured and numerically ...


Examining Bicycle And Motorized Vehicle Speeds And Their Relationships In The Context Of Urban Roadways, Jaclyn Sue Schaefer Dec 2020

Examining Bicycle And Motorized Vehicle Speeds And Their Relationships In The Context Of Urban Roadways, Jaclyn Sue Schaefer

Dissertations and Theses

This thesis presents a compilation of papers exploring passenger car and bicycle speeds through their interactions with each other and with urban roadway factors.

First, following a concern raised in part of the traffic literature that a large mode shift toward bicycling may cause travel time delays and potentially exacerbate congestion instead of alleviate it unless bicycle lanes are installed, an empirical study detailing how the presence of bicycles on urban roads without bicycle lanes may affect passenger car speeds is presented. Pneumatic tube data from six predominantly low speed, low volume roads in Portland, Oregon were utilized to identify ...


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. For this research, routes are divided into a consecutive group of bus stops ...


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 ...


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 ...


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 ...


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 ...


Statistical Modeling Of Historical Daily Water Temperatures In The Lower Columbia River, Malia Hanae Scott Jul 2020

Statistical Modeling Of Historical Daily Water Temperatures In The Lower Columbia River, Malia Hanae Scott

Dissertations and Theses

Water temperature affects numerous aspects of aquatic life, and its stability is critical to cold water fish such as salmonids. With rising anthropogenic influence in natural environments, the future existence of these organisms is becoming less certain. In this study, I examined the evolution of historical water temperatures in the lower Columbia River by creating a statistical model to estimate daily historical water temperatures between the 1850s and 2010s. Daily air temperature and river flow measurements were used as inputs to the model, which estimated daily water temperatures at Bonneville Dam. The model used time lags between air temperature and ...


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 ...


Memristive Architectures And Algorithms For Approximate Graph-Based Inference, Mohammad M.A. Taha Jul 2020

Memristive Architectures And Algorithms For Approximate Graph-Based Inference, Mohammad M.A. Taha

Dissertations and Theses

The goal of this thesis is to design fast, low-power, robust graph-based inference systems. Our approach to this is by using (1) in-memory computing, (2) approximate computing principles, and (3) memristive devices.

This work is motivated by the fact that conventional von Neumann architectures are not efficient for inference applications, mainly due to the data transfer bottleneck. Adding cache memories and using GPUs is a remedy, however, does not eliminate this bottleneck. In-memory computing is an alternative approach that performs all computations inside the memory, thus eliminating the data transfer bottleneck.

The memristor, which is a passive two-terminal device, is ...