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Can Diatom Motility Indices Reflect Excess Fine Sediment Condition In Streams?, Christine L. Weilhoefer, Yangdong Pan

Environmental Science and Management Faculty Publications and Presentations

The diatom motility trait is widely used in bioassessment studies, however, there is no strong consensus as to what environmental conditions diatom motility reflects. We used random forest models to explore the behavior of several diatom-based motility indices and examined whether stronger diatom motility-environmental relationships could be developed by controlling for environmental factors that influence natural sediment loads and factors that co-occur with anthropogenic sediment loading. Across the study area, median values of most stressors were low; streambed fine sediments ranged from 0 to 100% (median: 6.7%) and total phosphorus concentrations ranged from 0 to 2587 µg L−1 (median: 17 …

Ssita: Seal Serving Institutional Transformation Assessment: Excelencia In Education & Portland State University, Cynthia Carmina Gómez, Oscar Fernandez, Cristina Herrera, Emanuel Magaña, Allyson Meyers, Perla Pinedo, Rebecca Rodas, Tanya Sanchez

Global Diversity and Inclusion Publications and Presentations

In the Spring of 2022, Portland State University was invited to participate in Excelencia in Education’s pilot Seal Serving Institutional Transformation Assessment or SSITA. This SSITA report is a preliminary institutional assessment of Portland State University’s (PSU) efforts to intentionally serve Latiné students and advance degree completion. Between now and June 2023, a committee of faculty, staff, and students will lead the effort to complete a Seal of Excelencia application. We will reach out to all parts of the institution to gather additional information, data, and stories about how units serve our growing Latiné student population. The next round of …

Learning Nonparametric Ordinary Differential Equations: Application To Sparse And Noisy Data, Kamel Lahouel, Michael Wells, David Lovitz, Victor Rielly, Ethan Lew, Bruno Jedynak

Mathematics and Statistics Faculty Publications and Presentations

Learning nonparametric systems of Ordinary Differential Equations (ODEs) x˙=f(t,x) from noisy and sparse data is an emerging machine learning topic. We use the well-developed theory of Reproducing Kernel Hilbert Spaces (RKHS) to define candidates for f for which the solution of the ODE exists and is unique. Learning f consists of solving a constrained optimization problem in an RKHS. We propose a penalty method that iteratively uses the Representer theorem and Euler approximations to provide a numerical solution. We prove a generalization bound for the L2 distance between x and its estimator. Experiments are provided for the FitzHugh Nagumo oscillator …

The Average Number Of Divisors In Certain Arithmetic Sequences, Liubomir Chiriac

Mathematics and Statistics Faculty Publications and Presentations

In this paper we study the sum p≤xτ(np), where τ(n) denotes the number of divisors of n, and {np} is a sequence of integers indexed by primes. Under certain assumptions we show that the aforementioned sum is x as x → ∞. As an application, we consider the case where the sequence is given by the Fourier coefficients of a modular form.

Reducing Opioid Use Disorder And Overdose Deaths In The United States: A Dynamic Modeling Analysis, Erin J. Stringfellow, Tse Yang Lim, Keith Humphreys, Catherine Digennero, Celia Stafford, Elizabeth Beaulieu, Jack Homer, Wayne Wakeland, Multiple Additional Authors

Complex Systems Faculty Publications and Presentations

Opioid overdose deaths remain a major public health crisis. We used a system dynamics simulation model of the U.S. opioid-using population age 12 and older to explore the impacts of 11 strategies on the prevalence of opioid use disorder (OUD) and fatal opioid overdoses from 2022 to 2032. These strategies spanned opioid misuse and OUD prevention, buprenorphine capacity, recovery support, and overdose harm reduction. By 2032, three strategies saved the most lives: (i) reducing the risk of opioid overdose involving fentanyl use, which may be achieved through fentanyl-focused harm reduction services; (ii) increasing naloxone distribution to people who use opioids; …

A Multi-City Urban Atmospheric Greenhouse Gas Measurement Data Synthesis, Logan E. Mitchell, John C. Lin, Lucy R. Hutyra, David R. Bowling, Ronald C. Cohen, Kenneth J. Davis, Elizabeth Digangi, Riley M. Duren, Andrew Rice, Multiple Additional Authors

Physics Faculty Publications and Presentations

Urban regions emit a large fraction of anthropogenic emissions of greenhouse gases (GHG) such as carbon dioxide (CO2) and methane (CH4) that contribute to modern-day climate change. As such, a growing number of urban policymakers and stakeholders are adopting emission reduction targets and implementing policies to reach those targets. Over the past two decades research teams have established urban GHG monitoring networks to determine how much, where, and why a particular city emits GHGs, and to track changes in emissions over time. Coordination among these efforts has been limited, restricting the scope of analyses and insights. Here we present a …

Making Curry With Rice: An Optimizing Curry Compiler, Steven Libby

Dissertations and Theses

In this dissertation we present the RICE optimizing compiler for the functional logic language Curry. This is the first general optimizing compiler for a functional logic language. Our work is based on the idea of compiling through program transformations, which we have adapted from the functional language compiler community. We also present the GAS system for generating new program transformations, which uses the power of functional logic programming to provide a flexible framework for describing transformations. This allows us to describe and implement a wide range of optimizations including inlining, shortcut deforestation, unboxing, and case shortcutting, a new optimization we …

Exploring Structure-Function Relationship In Small-Molecular Catalysts Using Computational And Experimental Methodologies, Avik Bhattacharjee

Dissertations and Theses

Molecular modeling is a useful tool in the field of catalyst design for various processes. The use of Density Functional Theory (DFT) is routine in almost every discipline of chemistry. This allows for a deeper understanding of a molecular system even in situations where implementation of an experimental technique is unfeasible. However, without the right choice of theory and insufficient description, the model becomes susceptible to produce ambiguous results. This often leads to poor correlation with experimental findings hence an incomplete understanding of the system under study. Hence, to acquire a thorough knowledge of the intricacies involved in a system, …

A Multi‑Analytical Approach To Identify Red Colorants On Woodblock Prints Attributed To Suzuki Harunobu, Lyndsay Nichole Kissell, Trine K. Quady, Dario Durastanti, Samantha Springer, Jeannie Kenmotsu, Tami Lasseter Clare

Chemistry Faculty Publications and Presentations

Red organic dye identification is an important topic for conservation of Japanese ukiyo-e prints. Of particular interest are the works of Suzuki Harunobu, who was working at the inception of full-color printmaking. These prints were made on thin kōzo paper and woodblock printed with semi-transparent to opaque regions of dye(s) and/ or pigment(s) mixed with binder. This study used imaging analysis, X-ray fluorescence (XRF), Raman, and surfaceenhanced Raman spectroscopies (SERS) to identify the red dyes and pigments on Harunobu prints in the collection of the Portland Art Museum. Through image analysis (visible, UV, and IR illuminations), 23 prints were categorized …

Analytic Solution Of 1d Diffusion-Convection Equation With Varying Boundary Conditions, Małgorzata B. Glinowiecka-Cox

University Honors Theses

A diffusion-convection equation is a partial differential equation featuring two important physical processes. In this paper, we establish the theory of solving a 1D diffusion-convection equation, subject to homogeneous Dirichlet, Robin, or Neumann boundary conditions and a general initial condition. Firstly, we transform the diffusion-convection equation into a pure diffusion equation. Secondly, using a separation of variables technique, we obtain a general solution formula for each boundary type case, subject to transformed boundary and initial conditions. While eigenvalues in the cases of Dirichlet and Neumann boundary conditions can be constructed easily, the Robin boundary condition necessitates solving a transcendental algebraic …

Policing By Proxy: Interrogating Big Tech's Role In Law Enforcement, Claire Elizabeth

University Honors Theses

Predictive policing, sometimes referred to as data-driven or actuarial policing, is a method of policing that uses a risk-based approach to law enforcement. For-profit technology companies market proprietary risk assessment algorithms to law enforcement organizations as tools meant to proactively mitigate crime. Using data collected from a vast array of sources, both personal and public, police are able to "predict" the likelihood of criminal activity in a given area using these algorithms. Proponents claim that risk assessment tools have the potential to fight crime with unbiased accuracy and speed by predicting when, where, and whom to police by relying on …

Working Paper No. 64, Ecological Economics Versus Environmental Economics, Audrey Demeaux

Working Papers in Economics

This inquiry seeks to establish that the field within the Discipline of Economic Science known as Ecological Economics is based upon assumptions and methodological foundations that differ from the field of Environmental Economics. It shall be argued that Environmental Economics did not emerge as the result of a new shift in economic thinking, but rather formed around a reorientation of standard neoclassical assumptions. This was undertaken in an effort to address environmental issues emerging several decades back. In contrast, it shall be argued that the field of Ecological Economics has brought to the Economics Discipline an appreciation for novel assumptions …

Working Paper No. 55, An Inquiry Into The Assumptions And Tenets Of Neoclassical Economics That Lead Towards Income Inequality, Katharine Nester

Working Papers in Economics

This inquiry seeks to establish that key assumptions foundational to Neoclassical Economics contribute towards income inequality. A consideration of the Neoclassical interpretation and assumptions of the laissez-faire approach to market economies opens the inquiry. I examine the economic outcomes that result when the assumptions underpinning the Neoclassical application of laissez-faire are false, as they often are in the real world. The inquiry then turns to the theories and natural “laws” as advanced by Vilfredo Pareto (1848-1923) and John Bates (J. B.) Clark (1847-1938), which were built upon the Neoclassical adaptation of laissez-faire and became canon in the Neoclassical school. Finally, …

Detection And Quantification Of Arsenic Pollution With A Moss Bio-Indicator And Icp-Ms, Erin R. Bowey

University Honors Theses

Heavy metal pollution is a recognized concern with an established source of anthropogenic activity, which is ever-increasing. While work has been done to make the monitoring of some metals more accessible, resourceful, and efficient with the use of epiphytic moss as a bio-indicator, this method has not been optimized for the detection of arsenic. Previously used analytical instrumentation has not proven sensitive enough to reliably detect arsenic, creating a gap in the monitoring process. However, inductively coupled plasma mass spectrometry (ICP-MS) is proposed as the solution to fill this gap. Its potential for low limits of detection and quantification express …

Electron Backscatter Diffraction Analysis Of Olivine In Ureilite Meteorites: Evaluation Of The Partially Magmatic Catastrophic Disruption Model Of The Ureilite Parent Body (Upb), James Karl Frye

Dissertations and Theses

Past studies of olivine have yielded insights into crystallographic slip systems and how they are activated thermally. Using this information in conjunction with Electron Backscatter Diffraction (EBSD) analysis and metrics developed for chondrites, I constrained the thermal environment and the cooling rate for four ureilite meteorites in an attempt to test the model of catastrophic disruption of the ureilite parent body while it was partly molten. Present evidence for deformation, along with thermal metrics, were examined in order to conclude the following: Deformation of the meteorites took place at high temperatures followed by swift cooling, leaving little time for annealing. …

Examining Probation Lengths In Philadelphia, Pa, Madeline Grace Davis

Dissertations and Theses

One out of every 22 adults in Philadelphia, PA is under community supervision which is more than double the national average (Schiraldi, 2018). Even though probation has been seen as a more lenient alternative to prison it actually serves as a net-widener (Phelps, 2020). Probation can result in increased punishments for low-level offenses when failure to meet probation conditions results in jail or prison time when there was never a possibility of long-term incarceration at the time of sentencing (Phelps, 2020). This study uses public court information data from Philadelphia to analyze the effects different dosages of probation have on …

Investigating Student Engagement In General Chemistry Active Learning Activities Using The Activity Engagement Survey (Aces), Nicole Naibert, Jack Barbera

Chemistry Faculty Publications and Presentations

Investigating student engagement in active learning activities could provide valuable insight into variations of student learning outcomes when active learning is included in a course. This study sought to explore students’ engagement in relation to active learning activities incorporated in a general chemistry lecture course using the Activity Engagement Survey (AcES). The AcES can be used to simultaneously assess students’ overall engagement, as well as dimensions above and beyond overall engagement including their combined behavioral/cognitive engagement, emotional engagement, and social engagement. As students’ engagement may be influenced by aspects related to the learning environment and context, differences in engagement were …

Faculty Senate Monthly Packet June 2022, Portland State University Faculty Senate

Faculty Senate Monthly Packets

The June 2022 Monthly packet includes the May agenda and appendices and the Faculty Senate minutes and attachments from the meeting held May 5, 2022.

Transportation Mode Choice Behavior In The Era Of Autonomous Vehicles: The Application Of Discrete Choice Modeling And Machine Learning, Sangwan Lee

Dissertations and Theses

New mobility technologies, such as shared mobility services (e.g., car-sharing) and, more importantly, autonomous vehicles (AVs), continue to evolve. The supply-side advancement will likely disrupt and transform transportation mode choice behaviors, and create a new paradigm since they are emerging and becoming increasingly feasible alternatives to the existing modes of transportation. Accordingly, this dissertation employs discrete choice modeling (DCM) and machine learning (ML) using a U.S. nationwide stated choice experiment to understand how travelers adopt new transportation modes or continue to use conventional modes of transportation.

This dissertation consists of three papers. The first examines future market shares of each …

"We've Created Cheap Energy Off The Backs Of Salmon": Dam Removal Politics And Alliances In The Lower Snake River Basin, Krista Harrington

Dissertations and Theses

Dams, once considered by many to be good for water development in the Western U.S., might not be a part of a climate resilient future. Dams have come under increasing scrutiny due to undesirable ecological implications. Although dam removal proposals are growingly popular in recent decades, they are controversial since they impact different stakeholders in different ways. In the Pacific Northwest, the Lower four Snake River dams have long been criticized for their negative impacts on salmon. In February 2021, US Congressman Mike Simpson (R-Idaho) proposed a comprehensive framework to deconstruct the Lower four Snake River dams as an attempt …

Mapping Ecosystem Service Flows Of Estuary Restoration Projects On The Oregon Coast To Identify Impacted Stakeholders, Shersten King Finley

Dissertations and Theses

The recent impetus for estuarine restoration has largely focused on resolving key ecological problems; however, less is known about how people might benefit or be impacted by restoration. By mapping benefits that flow from functional salt marshes and estuarine systems I examined how different social groups might be impacted by restoration based on race and class. In this study, I considered three ecosystem services (recreation, aesthetics, cultural/historical/spiritual) and where they might impact surrounding communities. In this paper I argue that stakeholder groups can be identified by mapping ecosystem service flow areas. I hypothesized that these three ecosystem services would have …

The Future Of Camera Technology With Atul Ingle, Atul Ingle

PDXPLORES Podcast

Single-photon camera sensors have the potential to revolutionize digital camera technology. These sensors can capture individual photons at high speeds, circumventing some of the limitations of current digital camera technologies. One challenge, however, is the sheer amount of data generated by the sensor, which is a hindrance to their widespread adoption. With the support of the National Science Foundation, Assistant Professor Atul Ingle is developing algorithms to solve this problem--algorithms that could enable the adoption of single-photon sensors in applications ranging from autonomous vehicles to medical imaging and the cameras in cellphones.

A Three-Dimensional, Analytical Wind Turbine Wake Model: Flow Acceleration, Empirical Correlations, And Continuity, Zein Ahmad Sadek

Dissertations and Theses

A new, three-dimensional, analytical, steady state wake model is presented which includes local flow acceleration near the rotor improving wake description compared to existing models. Wake structures such as the momentum deficit and regions of accelerated flow are concisely described with compound and normal Gaussian functions. Large-eddy simulations (LES) are used as training data to develop the model using two, inline turbines under various inflow conditions parameterized by hub height wind speed and turbulence intensity. Mass conservation is considered by fixing two components of the wake velocity model and optimizing the third to best satisfy continuity; after which, the model …

Geochronological And Geochemical Investigation Into Rhyolite Volcanism Of The High Lava Plains And Columbia River Basalt Group Provinces Of Eastern Oregon, Usa, Vanessa Marie Swenton

Dissertations and Theses

Voluminous and widespread bimodal volcanism has significantly impacted the Pacific Northwest, USA, throughout the Miocene to present day. The two primary volcanic provinces of eastern Oregon include the Columbia River Basalt Group (CRBG) province and the High Lava Plains (HLP) trend. The magmatic and tectonic processes responsible for generating bimodal volcanism, and particularly rhyolites of the ~17-15 Ma CRBG and 12-0 Ma HLP provinces has recently been a popular topic of debate. Rhyolite volcanism of the HLP province has been ascribed to either buoyancy-driven westward plume spreading or to slab rollback and mantle convection spanning from southeast Oregon to Newberry …

An Examination Of Educator Perspectives On Career And College Pathways For Black, Indigenous, And Students Of Color With Disabilities, Rachel Anne Herrick

Dissertations and Theses

Black, Indigenous, and students of color (BIPOC students) in high school, who are dually experiencing the socially constructed labels of race and disability (BIPOC-SWD), are not provided with equitable access to Career and College Pathway (CCP) programs, which contributes to a lack of preparedness and success within postsecondary settings. Despite school reform policy efforts that incorporate Culturally Relevant Pedagogy (CRP) and Career and College Readiness frameworks, BIPOC-SWD perpetually have lower achievement rates, poorer postsecondary outcomes, and are less prepared for careers or college.

Utilizing a Disability Critical Race Theory (DisCrit) lens, this comparative case study was used to examine educator …

A New Approach To Machine Learning Hardware Classifier Design Based On Functional Decomposition Of Multi-Valued Functions, Saad Mohammad Al-Askaar

Dissertations and Theses

This dissertation presents a novel design of a hardware classifier based on combining modified Ashenhurst-Curtis Decomposition and multiplexer-based synthesis. The PSUD classifier brings three new contributions: an approach to solve the column multiplicity problem, an approach to encode multiple-valued variables, and a decomposition algorithm based on modified Ashenhurst-Curtis Decomposition. One of the biggest challenges in Boolean function decomposition is the variable partitioning problem. Thus, we introduce a new representation of two combined classifiers for multiple-valued functions to overcome the variable partitioning problem which allows finding the minimal column multiplicity and consequently to find high quality decompositions leading to a good …

A Bayesian Latent Scale Model For Multivariate Longitudinal Data, Kruti Pandya

Dissertations and Theses

In order to understand the entire course of slow progressing diseases like Alzheimer's dementia or multiple sclerosis, it is essential to characterize long term disease dynamics from a healthy stage to a late disease stage. Cohort studies typically recruit subjects at different stages of the disease and then follow them for a relatively short period of time. In this dissertation, we propose a novel Bayesian nonlinear mixed effects model with latent time scale to characterize long term disease dynamics using the observed short term longitudinal data from cohort studies without relying on clinical diagnosis. This model can accommodate noisy longitudinal …

Methodologies For Quantum Circuit And Algorithm Design At Low And High Levels, Edison Tsai

Dissertations and Theses

Although the concept of quantum computing has existed for decades, the technology needed to successfully implement a quantum computing system has not yet reached the level of sophistication, reliability, and scalability necessary for commercial viability until very recently. Significant progress on this front was made in the past few years, with IBM planning to create a 1000-qubit chip by the end of 2023, and Google already claiming to have achieved quantum supremacy. Other major industry players such as Intel and Microsoft have also invested significant amounts of resources into quantum computing research.

Any viable computing system requires both hardware and …

Basic Concepts Of Structural Design For Architecture Students, Anahita Khodadadi

PDXOpen: Open Educational Resources

This book aims to narrate fundamental concepts of structural design to architecture students such that they have minimum involvement with math problem-solving. Within this book, students learn about different types of loads, forces and vector addition, the concept of equilibrium, internal forces, geometrical and material properties of structural elements, and rules of thumb for estimating the proportion of some structural systems such as catenary cables and arches, trusses, and frame structures.

Please see the Open Textbook Library for faculty reviews of this textbook

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Lgbtq+ Social Services And Needs In Portland Oregon, Jay M. Tomlinson

University Honors Theses

Research shows a significant link between being LGBTQ+ and living in poverty, but little research has been done on what services are available to providers and individuals in need. This study was conducted to discover what types of social services are available to low-income LGBTQ+ people living in Portland, Oregon, and what services providers identify as unmet needs. This study consisted of a series of interviews with service providers to find out what services they offer and what they feel is still missing. Data was analyzed following a qualitative data analysis method. Data showed that housing was the largest unmet …