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Full-Text Articles in Engineering

Exploring How Antecedent Precipitation Amount And The Effects Of Covid-19 Affect Stormwater Runoff Quality Along Urban Gradients, Daniel Ramirez, Katherine Gelsey Aug 2021

Exploring How Antecedent Precipitation Amount And The Effects Of Covid-19 Affect Stormwater Runoff Quality Along Urban Gradients, Daniel Ramirez, Katherine Gelsey

REU Final Reports

Stormwater runoff quality is affected by a multitude of factors including surrounding land characteristics, human activities, and antecedent precipitation amounts. We explore how seasonal and variable precipitation affect E. Coli, total suspended solids, nitrogen-nitrate, orthophosphate, lead, and zinc concentrations in Portland, OR, USA. Correlation analysis was conducted between the pollutant concentrations and antecedent rainfall each sample site received for the previous 1, 3, 5, 7, and 30 days from when the sample was taken. We ran Mann-Whitney tests to determine if the levels of the pollutants were statistically different between the wet season and the dry season. We found that …


Modeling Renal Function During Pregnancy, Christina A. Valtierra Aug 2021

Modeling Renal Function During Pregnancy, Christina A. Valtierra

REU Final Reports

The main goal of this research project is to build a computational model that illustrates the main processes in renal function during pregnancy. The analysis of how pregnancy affects all the factors that take place within the kidney will allow for a better understanding of how pathologies like proteinuria, hypertension, and glomerular endotheliosis develop. This model is a small part of a more complex model that showcases the complete pathophysiology of preeclampsia.


E-Scooter Safety And How To Improve It, Eric Valentino Aug 2021

E-Scooter Safety And How To Improve It, Eric Valentino

altREU Projects

In the last few years, electronic scooters have taken over cities as a means of personal transportation. Between 2017 and 2019 alone, over 30 million trips were recorded across over 100 cities in the US. These scooters pose a safety risk, as 20 in 100,000 trips will result in injury of the rider. On top of this, scooters can cause damage to property, injury pedestrians and motor vehicle drivers, as well as obstruct important infrastructure such as wheelchair ramps. For these reasons, it is important to develop an understanding of the factors that contribute to e-scooter related injuries in order …


Assessing The Impact Of Changing Drought Conditions On Wildfire Emissions In Washington And Oregon, Maggie Liu Aug 2021

Assessing The Impact Of Changing Drought Conditions On Wildfire Emissions In Washington And Oregon, Maggie Liu

altREU Projects

Wildfires impact public health, and threaten life, livelihood, and property across the United States, particularly on the West Coast. This project seeks to find correlations between drought and wildfire emissions by comparing the Modified Palmer Drought Index (PMDI) with smoke particulate (PM2.5) emissions from fires in Oregon and Washington. PM2.5 emissions were taken from 2002 – 2020 from the National Center for Atmospheric Research’s FINN model, which uses satellite observations of active fires to assign burned area, and compares against observed vegetation to model emissions. This project found the strongest positive correlation between fire activity for a summer season (July …


Online Grocery Shopping: A Staple Of The Present -- And Maybe The Future?, Henry B. Chao Aug 2021

Online Grocery Shopping: A Staple Of The Present -- And Maybe The Future?, Henry B. Chao

altREU Projects

This project aims to understand how the COVID-19 pandemic has affected people's food shopping tendencies, specifically focusing on the use of online grocers. It uses data collected by a team of researchers led out of Portland State University. This data consists of roughly 8000 surveys distributed starting in September of 2020. The survey asks respondents to discuss their demographics, household resources, and shopping tendencies.

In particular, this project wants to understand how inclined a respondent is to use online grocers based on their personal experience with COVID-19. To do this, the project uses a Latent Class Model (LCM) to classify …


Modeling The Effect Of The Covid-19 Pandemic On Azithromycin Prescription In General Practices Across The Uk, Oluwasegun Isaac Daramola Aug 2021

Modeling The Effect Of The Covid-19 Pandemic On Azithromycin Prescription In General Practices Across The Uk, Oluwasegun Isaac Daramola

altREU Projects

In the early months of the COVID-19 pandemic, it was reported that some antibiotics were prescribed as a remedy for viral treatment and prophylaxis based on non-randomized, uncontrolled short clinical trials. A major antibiotic consulted being Azithromycin; a broad-spectrum macrolide selected based on its immunomodulatory effects in chronic inflammatory lung diseases, with a seasonal prescription increase of 21.5% in March 2020 compared to March 2019.

To analyze the effect and possible antimicrobial resistance impact of the pandemic on Azithromycin prescription across general practices in the United Kingdom (UK), this study uses a time series decomposition modeling method to compare a …


Developing A Strategy For Creating Affordable Student Housing Solutions, Juan D. Campolargo Aug 2021

Developing A Strategy For Creating Affordable Student Housing Solutions, Juan D. Campolargo

altREU Projects

College is becoming more and more expensive, and students are graduating with more and more debt. In 2021, we have almost 1.6 trillion dollars of student loan debt. While students are in college, they need a place to live, and this project will be about how to develop a strategy for creating affordable student housing solutions.

Housing should not be another cause of concern to students or really anyone.

The way it’s done is that people get more loans to pay for housing, or they work as much as they can when they’re not studying to pay for rent. Affordable …


Forest Park Trail Monitoring, Adan Robles, Colton S. Maybee, Erin Dougherty Aug 2021

Forest Park Trail Monitoring, Adan Robles, Colton S. Maybee, Erin Dougherty

REU Final Reports

Forest Park, one of the largest public parks in the United States with over 40 trails to pick from when planning a hiking trip. One of the main problems this park has is that there are too many trails, and a lot of the trails extend over 3 miles. Due to these circumstances’ trails are not checked frequently and hikers are forced to hike trails in the area with no warnings of potential hazards they can encounter. In this paper I researched how Forest Park currently monitors its trails and then set up a goal to solve the problem. We …


Finding Lonely Routes For Runners And Bikers, Ethan T. Spicher Aug 2021

Finding Lonely Routes For Runners And Bikers, Ethan T. Spicher

REU Final Reports

With COVID-19 raging around the world, personal health is even more important to a lot of people. One way to maintain good physical and mental health is to exercise according to Deslandes [2]. When exercising it may be important to make sure that you are running/biking on trails that are less populated than others, as well as taking into account the distance. This can be solved by creating an algorithm that allows the user to choose the starting and end point, and the algorithm will then find the optimal path between the two points with the distance and popularity of …


Digitally Reporting Trail Obstructions In Forest Park, Colton S. Maybee Aug 2021

Digitally Reporting Trail Obstructions In Forest Park, Colton S. Maybee

REU Final Reports

The inclusion of technology on the trail can lead to better experiences for everyone involved in the hobby. Hikers can play a more prominent role in the maintenance of the trails by being able to provide better reports of obstructions while directly on the trail. This paper goes into the project of revamping the obstruction report system applied at Forest Park in Portland, Oregon. Most of my contributions to the project focus on mobile app development with some research into path planning algorithms related to the continuations of this project.


Agent-Based Activity Generation Of Runners For City Infrastructure Planning, Quang Le Aug 2021

Agent-Based Activity Generation Of Runners For City Infrastructure Planning, Quang Le

REU Final Reports

Since the pandemic started, many gyms and indoor classes have been shut down to mitigate the spread of Coronavirus. Many people have been forced to get onto pavement streets to get some fresh air while running around and coping with the new reality. There are over 60 million runners in the U.S., and that number is growing rapidly during this time without any sign of stopping once life gets back to normal. In this project, an agent-based model has been developed to generate a set of routes that runners would take in their daily run in a neighborhood of Portland …


Multi-Agent Radiation Localization, Teresa Nguyen Aug 2021

Multi-Agent Radiation Localization, Teresa Nguyen

REU Final Reports

Advancement of radiation detection technology is an ongoing process, and adjustments are made based on pre-existing conditions of radiation presence--both natural and man made. Tools that are currently used for safely detecting radiation in urban environments exist in several forms: drones, robots, or handheld radiation detection devices. This is a harm reductive way to explore radiation-infected environments while preserving human health as best as possible. In order for these autonomous platforms to successfully detect radiation sources, an algorithm needs to be created that is capable of gathering crucial data on its own with little to no human interference. Machine learning …


Automated Statistical Structural Testing Techniques And Applications, Yang Shi Aug 2021

Automated Statistical Structural Testing Techniques And Applications, Yang Shi

Dissertations and Theses

Statistical structural testing(SST) is an effective testing technique that produces random test inputs from probability distributions. SST shows superiority in fault-revealing power over random testing and deterministic approaches since it heritages the merits from both of them. SST ensures testing thoroughness by setting up a probability lower-bound criterion for each structural cover element and test inputs that exercise a structural cover element sampled from the probability distribution, ensuring testing randomness. Despite the advantages, SST is not a widely used approach in practice. There are two major limitations. First, to construct probability distributions, a tester must understand the underlying software's structure, …


The Effect Of A Ferrite-Core Relay Vs. An Air-Core Relay On The Output Power Characteristics Of A Three-Coil Wireless Power Transfer System, Jakob L. White Aug 2021

The Effect Of A Ferrite-Core Relay Vs. An Air-Core Relay On The Output Power Characteristics Of A Three-Coil Wireless Power Transfer System, Jakob L. White

University Honors Theses

The purpose of this thesis is to determine the effect of using a ferrite-core relay on the output power characteristics of a three-coil, parallel-tuned, domino-resonator wireless power transfer (WPT) system in comparison to the effect of using an air-core relay in such a system. First, a general mathematical model is presented to describe both the ferrite-core-relay system and the air-core-relay system and to calculate their output power characteristics for seven different resistive loads at each of five different distance configurations between the coils. Next, experimental results are analyzed and compared to the mathematical results to confirm model accuracy. Finally, the …


Ronald E. Mcnair Scholars Program Profiles And Abstracts 2021, Mcnair Scholars Program Aug 2021

Ronald E. Mcnair Scholars Program Profiles And Abstracts 2021, Mcnair Scholars Program

McNair Symposium

This is the complete event program and provides presentation abstracts and biographies of McNair scholars and their mentors.


Quantum Grover's Oracles With Symmetry Boolean Functions, Peng Gao Aug 2021

Quantum Grover's Oracles With Symmetry Boolean Functions, Peng Gao

Dissertations and Theses

Quantum computing has become an important research field of computer science and engineering. Among many quantum algorithms, Grover's algorithm is one of the most famous ones. Designing an effective quantum oracle poses a challenging conundrum in circuit and system-level design for practical application realization of Grover's algorithm.

In this dissertation, we present a new method to build quantum oracles for Grover's algorithm to solve graph theory problems. We explore generalized Boolean symmetric functions with lattice diagrams to develop a low quantum cost and area efficient quantum oracle. We study two graph theory problems: cycle detection of undirected graphs and generalized …


Graphical Models In Reconstructability Analysis And Bayesian Networks, Marcus Harris, Martin Zwick Jul 2021

Graphical Models In Reconstructability Analysis And Bayesian Networks, Marcus Harris, Martin Zwick

Complex Systems Faculty Publications and Presentations

Reconstructability Analysis (RA) and Bayesian Networks (BN) are both probabilistic graphical modeling methodologies used in machine learning and artificial intelligence. There are RA models that are statistically equivalent to BN models and there are also models unique to RA and models unique to BN. The primary goal of this paper is to unify these two methodologies via a lattice of structures that offers an expanded set of models to represent complex systems more accurately or more simply. The conceptualization of this lattice also offers a framework for additional innovations beyond what is presented here. Specifically, this paper integrates RA and …


An Analysis Of Capillary Flow In Finite Length Interior Corners, Samuel Shaw Mohler Jul 2021

An Analysis Of Capillary Flow In Finite Length Interior Corners, Samuel Shaw Mohler

Dissertations and Theses

We analyze the mathematical robustness of slow massively parallel interior corner flows in low gravity environments. An interior corner provides a preferential orientation in low gravity environments. This is a luxury usually only found on earth. It also provides a passive pumping mechanism due to geometry of a conduit. The driving force for this flow is a pressure difference due to local surface curvature gradients. An alternative reasoning is that due to the geometrical constraints the interior corner surface energy is unbounded below. This results in the liquid wicking into corners indefinitely. Interior corner flow's main quantity of interest is …


Kinematic Demands On Pile-Supported Wharves Due To Liquefaction-Induced Lateral Ground Deformations, Thomas John Torkelson Ii Jul 2021

Kinematic Demands On Pile-Supported Wharves Due To Liquefaction-Induced Lateral Ground Deformations, Thomas John Torkelson Ii

Dissertations and Theses

Kinematic demands from lateral soil deformations can be a major cause of damage to maritime and highway transportation structures such as wharves, ports, and bridges. Data from five centrifuge tests on pile-supported wharves were used to evaluate the accuracy of Newmark Sliding Block Analysis in estimating the kinematic demands on piles. The piles in the centrifuge tests were subjected to varying degrees of liquefaction-induced lateral ground deformations. Pile-pinning effects were included in the analysis by incorporating the lateral pile resistance in the limit-equilibrium slope stability analysis. The results of the analysis have shown that the median Newmark displacements better estimated …


Modeling Cyanotoxin Production, Fate And Transport In Surface Waterbodies, Bernadel Rose Hintz Garstecki Jul 2021

Modeling Cyanotoxin Production, Fate And Transport In Surface Waterbodies, Bernadel Rose Hintz Garstecki

Dissertations and Theses

Cyanobacteria exist throughout the world and are frequently associated with forming toxic blooms. The toxins produced by cyanobacteria, cyanotoxins, are harmful to both humans and animals. Rising temperatures due to global climate change, increased nutrient loading, and other anthropogenic impacts on waterbodies are expected to increase the prevalence of cyanobacteria. It is vital that we protect our drinking water supplies and natural water resources. Modeling the production and movement of these toxins is an important step in limiting exposure to them and evaluating management strategies to mitigate their impact. Cyanotoxins are diverse and the conditions under which they are formed …


Field Trials And Long-Term Monitoring Of Microbially-Induced Desaturation For The Treatment Of Liquefiable Silty Soils, Kayla Rae Sorenson Jul 2021

Field Trials And Long-Term Monitoring Of Microbially-Induced Desaturation For The Treatment Of Liquefiable Silty Soils, Kayla Rae Sorenson

Dissertations and Theses

Earthquake liquefaction hazards in silty soils are a critical problem in Portland, Oregon, and other areas around the world. This is a particular problem for existing facilities founded on liquefiable soils, for which there exists no cost-effective liquefaction mitigation solution at the present time. It is essential from both a seismic safety and a seismic resilience perspective to be able to mitigate potentially liquefiable soils underneath existing structures, and to do so in a cost-effective manner. Recent studies suggest that liquefaction mitigation using microbially-induced desaturation (MID) may provide this capability.

The objective of MID is to reduce earthquake-induced excess pore …


Using Quantitative Stereology On High Resolution Sem Images To Estimate Diatom Percentages, Ariadna Covarrubias Ornelas Jul 2021

Using Quantitative Stereology On High Resolution Sem Images To Estimate Diatom Percentages, Ariadna Covarrubias Ornelas

Dissertations and Theses

Diatoms are single-celled organisms of various shapes and sizes typically found in aquatic environments. When diatoms die, the organic material decomposes, and the outer skeletons (i.e., frustules) settle and accumulate as sedimentary deposits. These soils, called diatomaceous soils, exhibit nontraditional behavior since the diatom particles are typically hollow skeletons composed of amorphous silica with intricately patterned and abrasive surfaces. Recent studies have shown that diatomaceous soils are challenging geomaterials since even a small percentage of diatom particles will notably affect engineering behavior. Furthermore, laboratory studies on diatomaceous soil mixtures have demonstrated that many engineering soil properties depend on the percentage …


Fixed Bottom Wind Turbine Wave-Wake Interaction, Ondrej Fercak Jul 2021

Fixed Bottom Wind Turbine Wave-Wake Interaction, Ondrej Fercak

Dissertations and Theses

The interest and benefits of offshore wind energy has also brought along legitimate design challenges for engineers. Most notably, the complex interaction between wind and turbine is further complicated by the addition of dynamic ocean waves. This dynamic coupling between wind, wave, and turbine is not fully understood. Even small improvements in wind turbine performance are welcome, so characterizing a fundamental dynamic in offshore energy is necessary to optimize design. Experimentation and simulation have been used to characterize inflow and turbine wakes and separately, wind-wave interactions. But only simulations have just begun to look at the wind, wave, and turbine …


Simulation Of Light Propagation Captured By Photoemission Electron Microscopy (Peem), Nabila Islam Jul 2021

Simulation Of Light Propagation Captured By Photoemission Electron Microscopy (Peem), Nabila Islam

Dissertations and Theses

The Photoemission electron microscopes (PEEM) is a powerful tool capable of synchronously imaging wave nature of light manifested by interference patterns as well as its particle nature through the energy exchange between the incident photons and the photoemitted imaging electrons. PEEM offers a non-invasive high-resolution approach for studying light propagation and interaction phenomena within a nanophotonic waveguide [7,8]. The electric field intensity variation of the interference pattern yielded by the interaction between the incident light and the guided mode coupled into the waveguide produces varying photoemission yields creating contrast in PEEM image. The guided modes cannot be excited simply by …


Differing Effects Of Four Building Materials On Viable Bacterial Communities And Vocs, Gwynne Á. Mhuireach, Leslie Dietz, Willem Griffiths, Patrick Finn Horve, Aurélie Laguerre, Dale Northcutt, Roo Vandegrift, Elliott T. Gall, Kevin Van Den Wymelenberg Jul 2021

Differing Effects Of Four Building Materials On Viable Bacterial Communities And Vocs, Gwynne Á. Mhuireach, Leslie Dietz, Willem Griffiths, Patrick Finn Horve, Aurélie Laguerre, Dale Northcutt, Roo Vandegrift, Elliott T. Gall, Kevin Van Den Wymelenberg

Mechanical and Materials Engineering Faculty Publications and Presentations

Indoor environmental quality is a paramount concern among architects. Exposure to VOCs and microorganisms impacts occupant health, yet the role of materials on these exposures remains poorly understood. In this study, we placed four material types in individual microcosms to test whether material type influences bacterial community structure and VOC emission. We used culture-independent methods to characterize bacterial communities and TD-GC-MS to measure VOC emission. We found that viable bacterial communities had different patterns of abundance, diversity, and composition, in comparison with total (viable plus dead cells) bacterial communities. Examining viable bacteria only, Earth had the highest abundance and diversity, …


Amazon Robotic Service (Ars), Patil Girija, John Mareena, Jin Fenny, Kandula Swapna, Ketsaraporn Kaewkhiaolueang Jul 2021

Amazon Robotic Service (Ars), Patil Girija, John Mareena, Jin Fenny, Kandula Swapna, Ketsaraporn Kaewkhiaolueang

Engineering and Technology Management Student Projects

Warehouse robots are the most effective replacement to minimize the pressure and availability of manual labor. The warehouse robots are mainly used for heavy lifting, picking up packages, transporting, and other tasks in the facility. The growing market of Internet of Things, Artificial Intelligence, and machine learning in the warehouse industry is forecasted to grow in the robots market in the near future. In order to build the final product i.e technology roadmap our team did market research, analysed competitors for the company, identified target customers, analyzed market, product and pricing strategy and at the end came up with the …


Assessment Of Heat-Affected Zone Softening Of Hot-Press-Formed Steel Over 2.0 Gpa Tensile Strength With Bead-On-Plate Laser Welding, Kwangsoo Kim, Namhyun Kang, Minjung Kang, Cheolhee Kim Jul 2021

Assessment Of Heat-Affected Zone Softening Of Hot-Press-Formed Steel Over 2.0 Gpa Tensile Strength With Bead-On-Plate Laser Welding, Kwangsoo Kim, Namhyun Kang, Minjung Kang, Cheolhee Kim

Mechanical and Materials Engineering Faculty Publications and Presentations

High-strength hot-press-formed (HPF) steels with a fully martensitic microstructure are being widely used in the fabrication of automotive body structure, and 2.0 GPa-strength HPF steel has recently been commercially launched. However, heat-affected zone (HAZ) softening is unavoidable in welding martensitic steel. In this study, the HAZ softening characteristic of 2.0 GPa HPF steel was investigated by applying a high-brightness laser welding process, wherein the heat input was controlled by varying the welding speed. Microstructural evaluation and hardness test results showed that the base metal with a fully martensitic microstructure was changed to the same type of fully martensitic microstructure in …


Optimization Of 3d Printed Mold Performance For Injection Molding Via Hollow Infill Patterns, Alan Fong Jul 2021

Optimization Of 3d Printed Mold Performance For Injection Molding Via Hollow Infill Patterns, Alan Fong

University Honors Theses

The applicability of hollow infill patterns has been explored for its applications in making 3D printed polymer-based injection molds in the additive manufacturing industry. Hollow infill patterns offer a significant reduction in material costs as well as the opportunity for reducing the cooling times via pumping a coolant fluid through the hollow cavity in a similar fashion to traditional conformal cooling channels. A 3D Jacks Support Hollow mold model was determined to be the best performing design. FEA analysis was conducted to determine the maximum reduction in internal volume (percentage of material saved) that could be achieved without exceeding the …


Comparing Instruments For Measuring Runoff From Experimental Ecoroof Platforms: A Case Study On Test Plots At Portland State University, Chance F. Hodges Jul 2021

Comparing Instruments For Measuring Runoff From Experimental Ecoroof Platforms: A Case Study On Test Plots At Portland State University, Chance F. Hodges

University Honors Theses

Stormwater management is a primary ecological benefit ecoroofs provide to ecosystems. Quantification of runoff from large scale ecoroofs is difficult to replicate, so researchers often utilize smaller experimental ecoroof platforms. This approach is becoming increasingly common, so it is useful to compare and contrast approaches for runoff measurement at the platform scale. This paper uses the four 17.86 m2 ecoroof platforms located on the Science Research and Teaching Center (SRTC) at Portland State University (PSU) in Portland, OR as a case study. A unique condition of these platforms is that they are installed at grade on the roof with …


Flavour Chemicals, Synthetic Coolants And Pulegone In Popular Mint-Flavoured And Menthol-Flavoured E-Cigarettes., Esther E. Omaiye, Wentai Luo, Kevin J. Mcwhirter, James F. Pankow, Prue Talbot Jun 2021

Flavour Chemicals, Synthetic Coolants And Pulegone In Popular Mint-Flavoured And Menthol-Flavoured E-Cigarettes., Esther E. Omaiye, Wentai Luo, Kevin J. Mcwhirter, James F. Pankow, Prue Talbot

Civil and Environmental Engineering Faculty Publications and Presentations

The Food and Drug Administration (FDA) has recently banned flavours from pod-style electronic cigarettes (e-cigarettes), except for menthol and tobacco. JUUL customers have quickly discovered that flavoured disposable e-cigarettes from other manufacturers, such as Puff, are readily available. Our goal was to compare flavour chemicals, synthetic coolants and pulegone in mint-flavoured/menthol-flavoured e-cigarettes from JUUL and Puff, evaluate the cytotoxicity of the coolants and perform a cancer risk assessment for pulegone, which is present in both JUUL pods and disposable Puff products.