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Is This Science? Students' Experiences Of Failure Make A Research-Based Course Feel Authentic, Emma C. Goodwin, Vladimir Anokhin, Mackenzie J. Gray, Daniel E. Zajic, Jason Podrabsky, Erin E. Shortlidge Mar 2021

Is This Science? Students' Experiences Of Failure Make A Research-Based Course Feel Authentic, Emma C. Goodwin, Vladimir Anokhin, Mackenzie J. Gray, Daniel E. Zajic, Jason Podrabsky, Erin E. Shortlidge

Biology Faculty Publications and Presentations

Course-based undergraduate research experiences (CUREs) and inquiry-based curricula both expose students to the scientific process. CUREs additionally engage students in novel and scientifically relevant research, with the intention of providing an "authentic" research experience. However, we have little understanding of which course design elements impact students' beliefs that they are experiencing "authentic" research. We designed a study to explore introductory biology students' perceptions of research authenticity in CURE and inquiry classes. Using the Laboratory Course Assessment Survey, we found that students in CURE sections perceived higher levels of authentic research elements than students in inquiry-based sections. To identify specific factors …

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Evaluating A Commercially Available In-Duct Bipolar Ionization Device For Pollutant Removal And Potential Byproduct Formation, Yicheng Zeng, Prashik Manwatkar, Aurelie Laguerre, Marina Beke, Insung Kang, Akram S. Ali, Delphine K. Farmer, Elliott T. Gall, Mohammad Heidarinejad, Brent Stephens Mar 2021

Evaluating A Commercially Available In-Duct Bipolar Ionization Device For Pollutant Removal And Potential Byproduct Formation, Yicheng Zeng, Prashik Manwatkar, Aurelie Laguerre, Marina Beke, Insung Kang, Akram S. Ali, Delphine K. Farmer, Elliott T. Gall, Mohammad Heidarinejad, Brent Stephens

Mechanical and Materials Engineering Faculty Publications and Presentations

We conducted a series of experiments to evaluate the gas and particle removal effectiveness and potential for byproduct formation resulting from the operation of a commercially available in-duct bipolar ionization device. Laboratory tests were conducted with the ionizer installed in a small air handler serving a large semi-furnished chamber. Chamber experiments were conducted under (i) normal operating conditions to characterize the impact of the ionizer on concentrations of particles (0.01–10 μm), ozone (O3), nitrogen dioxide (NO2), volatile organic compounds (VOCs), and aldehydes, and (ii) particle injection and decay conditions to characterize the impact of the ionizer operation on particle loss …

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Inferring The Subsurface Geometry And Strength Of Slow-Moving Landslides Using 3-D Velocity Measurements From The Nasa/Jpl Uavsar, Alexander L. Handwerger, Adam M. Booth, Mong-Han Huang, Eric J. Fielding Mar 2021

Inferring The Subsurface Geometry And Strength Of Slow-Moving Landslides Using 3-D Velocity Measurements From The Nasa/Jpl Uavsar, Alexander L. Handwerger, Adam M. Booth, Mong-Han Huang, Eric J. Fielding

Geology Faculty Publications and Presentations

The hazardous impact and erosive potential of slow‐moving landslides depends on landslide properties including velocity, size, and frequency of occurrence. However, constraints on size, in particular, subsurface geometry, are lacking because these types of landslides rarely fully evacuate material to create measurable hillslope scars. Here, we use pixel offset tracking with data from the NASA/JPL Uninhabited Aerial Vehicle Synthetic Aperture Radar to measure the three‐dimensional surface deformation of 134 slow‐moving landslides in the northern California Coast Ranges. We apply volume conservation to infer the actively deforming thickness, volume, geometric scaling, and frictional strength of each landslide. These landslides move at …

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Group Theory Visualized Through The Rubik's Cube, Ashlyn Okamoto Feb 2021

Group Theory Visualized Through The Rubik's Cube, Ashlyn Okamoto

University Honors Theses

In my thesis, I describe the work done to implement several Group Theory concepts in the context of the Rubik’s cube. A simulation of the cube was constructed using Processing-Java and with help from a YouTube series done by TheCodingTrain. I reflect on the struggles and difficulties that came with creating this program along with the inspiration behind the project. The concepts that are currently implemented at this time are: Identity, Associativity, Order, and Inverses. The functionality of the cube is described as it moves like a regular cube but has extra keypresses that demonstrate the concepts listed. Each concept …

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Combating Ecosystem Collapse From The Tropics To The Antarctic, Dana M. Bergstrom, Barbara C. Wienecke, John Van Den Hoff, Lesley Hughes, David B. Lindenmayer, Tracy D. Ainsworth, Christopher M. Baker, Lucie Bland, David M J S Bowman, Shaun T. Brooks, Josep G. Canadell, Andrew J. Constable, Katherine A. Dafforn, Michael H. Depledge, Catherine R. Dickson, Norman C. Duke, Kate J. Helmstedt, Andrés Holz Feb 2021

Combating Ecosystem Collapse From The Tropics To The Antarctic, Dana M. Bergstrom, Barbara C. Wienecke, John Van Den Hoff, Lesley Hughes, David B. Lindenmayer, Tracy D. Ainsworth, Christopher M. Baker, Lucie Bland, David M J S Bowman, Shaun T. Brooks, Josep G. Canadell, Andrew J. Constable, Katherine A. Dafforn, Michael H. Depledge, Catherine R. Dickson, Norman C. Duke, Kate J. Helmstedt, Andrés Holz

Geography Faculty Publications and Presentations

Globally, collapse of ecosystems-potentially irreversible change to ecosystem structure, composition and function-imperils biodiversity, human health and well-being. We examine the current state and recent trajectories of 19 ecosystems, spanning 58° of latitude across 7.7 M km , from Australia's coral reefs to terrestrial Antarctica. Pressures from global climate change and regional human impacts, occurring as chronic 'presses' and/or acute 'pulses', drive ecosystem collapse. Ecosystem responses to 5-17 pressures were categorised as four collapse profiles-abrupt, smooth, stepped and fluctuating. The manifestation of widespread ecosystem collapse is a stark warning of the necessity to take action. We present a three-step assessment and …

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Internationalization Of Environmental Education For Global Citizenship, Bowen Mcbeath, Qing Tian, Chen Wang, Bin Xu Feb 2021

Internationalization Of Environmental Education For Global Citizenship, Bowen Mcbeath, Qing Tian, Chen Wang, Bin Xu

School of Social Work Faculty Publications and Presentations

We present a teaching-and-learning case study of a 2018–2019 university-based summer institute in Beijing, China that concerned environmental education in support of global citizenship, involving Chinese and international faculty from education, social work, and related disciplines. The case study identifies: (1) the context of the summer institute; (2) its goals, design, and basic content; and (3) lessons learned for social work education. Specific attention is paid to: the importance of connecting university-based ecosocial work education with community-based practice in a Chinese context; addressing global social and environmental justice concerns through rural collaborative problem-solving; and navigating disciplinary boundaries involving social work …

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Alpine Ice-Core Evidence Of A Large Increase In Vanadium And Molybdenum Pollution In Western Europe During The 20th Century, Monica M. Arienzo, Michel Legrand, Susanne Preunkert, Andreas Stohl, Nathan Chellman, Sabine Eckhardt, Kelly E. Gleason, Joseph R. Mcconnell Feb 2021

Alpine Ice-Core Evidence Of A Large Increase In Vanadium And Molybdenum Pollution In Western Europe During The 20th Century, Monica M. Arienzo, Michel Legrand, Susanne Preunkert, Andreas Stohl, Nathan Chellman, Sabine Eckhardt, Kelly E. Gleason, Joseph R. Mcconnell

Environmental Science and Management Faculty Publications and Presentations

Pollutants emitted by industrial processes are deposited across the landscape. Ice core records from mid‐latitude glaciers located close to emission sources document the history of local‐to‐regional pollution since preindustrial times. Such records underpin attribution of pollutants to specific emission sources critical to developing abatement policies. Previous ice core studies from the Alps document the overall magnitude and timing of pollution related to nitrogen and sulfur‐derived species, as well as a few metals including lead. Here, we used subannually resolved measurements of vanadium (V) and molybdenum (Mo) in two ice cores from Col du Dome (French Alps), as well as atmospheric …

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Public Perceptions Of Ocean Health And Marine Protection: Drivers Of Support For Oregon’S Marine Reserves, Paul Manson, Max Nielsen-Pincus, Elise F. Granek, Thomas C. Swearingen Feb 2021

Public Perceptions Of Ocean Health And Marine Protection: Drivers Of Support For Oregon’S Marine Reserves, Paul Manson, Max Nielsen-Pincus, Elise F. Granek, Thomas C. Swearingen

Environmental Science and Management Faculty Publications and Presentations

Over the past several decades marine conservation policy has supported the implementation of protected areas in ocean and coastal environments to restrict some elements of human use for ecological benefits. The appropriate extent of protection and the allowable uses are often the subject of public debate about marine protected area policy. Local community dynamics around marine protected area designation and management have been the subject of much ocean and coastal management social science research. However, broader public opinions and attitudes about marine protected areas are not well understood and are critical for managers seeking to maintain their public trust obligations …

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Using The Gouy Phase Anomaly To Localize And Track Bacteria In Digital Holographic Microscopy 4d Images, True Gibson, Manuel Bedrossian, Eugene Serabyn, Chris Lindensmith, Jay Nadeau Feb 2021

Using The Gouy Phase Anomaly To Localize And Track Bacteria In Digital Holographic Microscopy 4d Images, True Gibson, Manuel Bedrossian, Eugene Serabyn, Chris Lindensmith, Jay Nadeau

Physics Faculty Publications and Presentations

Described over 100 years ago, the Gouy phase anomaly refers to the additional π phase shift that is accumulated as a wave passes through focus. It is potentially useful in analyzing any type of phase-sensitive imaging; in light microscopy, digital holographic microscopy (DHM) provides phase information in the encoded hologram. One limitation of DHM is the weak contrast generated by many biological cells, especially unpigmented bacteria. We demonstrate here that the Gouy phase anomaly may be detected directly in the phase image using the z-derivative of the phase, allowing for precise localization of unlabeled, micrometer-sized bacteria. The use of dyes …

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The Influence Of Spaceflight And Simulated Microgravity On Bacterial Motility And Chemotaxis, Jacqueline Acres, Myka Jaap Youngapelian, Jay Nadeau Feb 2021

The Influence Of Spaceflight And Simulated Microgravity On Bacterial Motility And Chemotaxis, Jacqueline Acres, Myka Jaap Youngapelian, Jay Nadeau

Physics Faculty Publications and Presentations

As interest in space exploration rises, there is a growing need to quantify the impact of microgravity on the growth, survival, and adaptation of microorganisms, including those responsible for astronaut illness. Motility is a key microbial behavior that plays important roles in nutrient assimilation, tissue localization and invasion, pathogenicity, biofilm formation, and ultimately survival. Very few studies have specifically looked at the effects of microgravity on the phenotypes of microbial motility. However, genomic and transcriptomic studies give a broad general picture of overall gene expression that can be used to predict motility phenotypes based upon selected genes, such as those …

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Distribution And Antibiotic Resistance Profiles Of Salmonella Enterica In Rural Areas Of North Carolina After Hurricane Florence In 2018, Yuqing Mao, Mohamed Zeineldin, Moiz Usmani, Sital Uprety, Joanna Shisler, Antarpreet Jutla, Avinash Unnikrishnan, Thanh H. Nguyen Feb 2021

Distribution And Antibiotic Resistance Profiles Of Salmonella Enterica In Rural Areas Of North Carolina After Hurricane Florence In 2018, Yuqing Mao, Mohamed Zeineldin, Moiz Usmani, Sital Uprety, Joanna Shisler, Antarpreet Jutla, Avinash Unnikrishnan, Thanh H. Nguyen

Civil and Environmental Engineering Faculty Publications and Presentations

The frequency and magnitude of extreme events are increasing globally (Arnell & Gosling, 2016). Inundation, as a result of massive flooding, has the potential to change environmental conditions abruptly, and as a result, add pressure to the metabolism and proliferation of microorganisms (Furtak et al., 2020). The resulting overland flows and additional burden from domestic sewer and septic tank systems during an extreme flood event can introduce pathogens into ecologically unstable water bodies. For example, Yu et al. (2018) reported elevated levels of Escherichia coli and antibiotic resistance genes (ARGs) in river water samples 6 months after flooding in Houston, …

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Modeling The Effectiveness Of Cooling Trenches For Stormwater Temperature Mitigation, Scott A. Wells Jan 2021

Modeling The Effectiveness Of Cooling Trenches For Stormwater Temperature Mitigation, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

Due to elevated runoff stormwater temperatures from impervious areas, one management strategy to reduce stormwater temperature is the use of underground flow through rock media termed a cooling trench. This paper examines the governing equations for the liquid phase and media phases for modeling the temperature leaving a cooling trench assuming that changes in temperature occurred longitudinally through the cooling trench. This model is dependent on parameters such as the media type, porosity, media initial temperature, inflow rate, and inflow temperature. Several approaches were explored mathematically for evaluating the change in temperature of the water and the cooling trench media. …

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Forecasting Optimal Parameters Of The Broken Wing Butterfly Option Strategy Using Differential Evolution, David Munoz Constantine Jan 2021

Forecasting Optimal Parameters Of The Broken Wing Butterfly Option Strategy Using Differential Evolution, David Munoz Constantine

Dissertations and Theses

Obtaining an edge in financial markets has been the objective of many hedge funds, investors, and market participants. Even with today's abundance of data and computing power, few individuals achieve a consistent edge over an extended time. To obtain this edge, investors usually use options strategies. The Broken Wing Butterfly (BWB) is an options strategy that has increased in popularity among traders. Profit is generated primarily by exploiting option value time decay. In this thesis, the selection of entry and exit BWB parameters, such as profit and loss targets, are optimized for an in-sample period. Afterward, they are used to …

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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 …

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Niche Partitioning Of Low-Light Adapted Prochlorococcus Subecotypes Across Oceanographic Gradients Of The North Pacific Subtropical Front, Anne W. Thompson, Kathleen Kouba, Nathan A. Ahlgren Jan 2021

Niche Partitioning Of Low-Light Adapted Prochlorococcus Subecotypes Across Oceanographic Gradients Of The North Pacific Subtropical Front, Anne W. Thompson, Kathleen Kouba, Nathan A. Ahlgren

Biology Faculty Publications and Presentations

The cyanobacterium Prochlorococcus is the most abundant photosynthetic cell on Earth and contributes to global ocean carbon cycling and food webs. Prochlorococcus is known for its extensive diversity that falls into two groups of ecotypes, the low‐light (LL) and high‐light (HL) adapted ecotypes. Previous work has shown niche partitioning of the very abundant HL adapted ecotypes and subecotypes across oceanographic gradients including temperature, nutrients, and day length. However, niche partitioning of subecotypes within the LL adapted ecotypes has not been studied as well because they are less abundant and less accessible than surface, HL populations. Through high‐throughput, cyanobacterial‐specific, sequencing of …

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Stability Conditions For Coupled Autonomous Vehicles Formations, Pablo Baldivieso, J. J. P. Veerman Jan 2021

Stability Conditions For Coupled Autonomous Vehicles Formations, Pablo Baldivieso, J. J. P. Veerman

Mathematics and Statistics Faculty Publications and Presentations

In this paper, we give necessary conditions for stability of coupled autonomous vehicles in R. We focus on linear arrays with decentralized vehicles, where each vehicle interacts with only a few of its neighbors. We obtain explicit expressions for necessary conditions for stability in the cases that a system consists of a periodic arrangement of two or three different types of vehicles, i.e. configurations as follows: 2-1-2-1 or 3-2-1-3-2-1. Previous literature indicated that the (necessary) condition for stability in the case of a single vehicle type (1-1-1) held that the first moment of certain coefficients of the interactions between vehicles …

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A Defense Of Locke’S Moral Epistemology, Jamie J. Hardy Jan 2021

A Defense Of Locke’S Moral Epistemology, Jamie J. Hardy

Philosophy Faculty Publications and Presentations

In An Essay Concerning Human Understanding, John Locke provides an empirical account of all of our ideas, including our moral ideas. However, Locke’s account of moral epistemology is difficult to understand leading to mistaken objections to his moral epistemological theory. In this paper, I offer what I believe to be the correct account of Locke’s moral epistemology. This account of his moral epistemology resolves the objections that morality is not demonstrable, that Locke’s account fails to demonstrate the normativity of statements, and that Locke has not provided us with the means to determine the correctness of the moral rules.

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Probability Axioms And Set Theory Paradoxes, Ari Herman, John Caughman Jan 2021

Probability Axioms And Set Theory Paradoxes, Ari Herman, John Caughman

Mathematics and Statistics Faculty Publications and Presentations

In this paper, we show that Zermelo–Fraenkel set theory with Choice (ZFC) conflicts with basic intuitions about randomness. Our background assumptions are the Zermelo–Fraenekel axioms without Choice (ZF) together with a fragment of Kolmogorov’s probability theory. Using these minimal assumptions, we prove that a weak form of Choice contradicts two common sense assumptions about probability—both based on simple notions of symmetry and independence.

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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 …

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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 …

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Amount And Depositional Fate Of Carbon Mobilized By Landsliding In Se Alaska, Bryce Alois Vascik Jan 2021

Amount And Depositional Fate Of Carbon Mobilized By Landsliding In Se Alaska, Bryce Alois Vascik

Dissertations and Theses

Forest disturbances in the form of landslides mobilize carbon (C) sequestered in vegetation and soils. The mobilized C has two basic depositional fates, deposition onto hillslopes or into water, which sequester C from and release C to the atmosphere at different time scales. The C-dense old-growth temperate forests of SE Alaska are a unique location to quantify the C mobilization rate by frequent landslide events. In this study, we estimate the amount of C mobilized by debris flows over historic time scales by combining a landslide inventory with maps of modeled biomass and soil carbon. We then infer depositional fate …

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Reassessing Hydrothermal Heat Discharge And The Relationship Of Hot Springs In The North Oregon Cascades, Aaron Alexander Orr Jan 2021

Reassessing Hydrothermal Heat Discharge And The Relationship Of Hot Springs In The North Oregon Cascades, Aaron Alexander Orr

Dissertations and Theses

Reservoir temperatures of hydrothermal systems in the Pacific Northwest reflect the feasibility of geothermal energy production and the tectonic framework of the region. Multicomponent geothermometry techniques were applied to new and historic water chemistry data in the north-central Oregon Western Cascades and the lower Wind River Valley in southern Washington in order to recalculate reservoir temperatures. Revised reservoir temperatures, water chemistry, and isotope data were used to determine relationships between hot springs in the north-central Oregon Cascades. Geothermal reservoir temperatures were estimated for the lower Wind River Valley (98.44 ± 0.96°C) and for Austin and Bagby Hot Springs (100.10 ± …

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Rock Glaciers And Related Cold Rocky Landforms: Overlooked Climate Refugia For Mountain Biodiversity, Stefano Brighenti, Scott Hotaling, Debra S. Finn, Andrew G. Fountain, Masaki Hayashi, David Herbst, Jasmine E. Saros, Lusha M. Tronstad, Constance I. Millar Jan 2021

Rock Glaciers And Related Cold Rocky Landforms: Overlooked Climate Refugia For Mountain Biodiversity, Stefano Brighenti, Scott Hotaling, Debra S. Finn, Andrew G. Fountain, Masaki Hayashi, David Herbst, Jasmine E. Saros, Lusha M. Tronstad, Constance I. Millar

Geology Faculty Publications and Presentations

Mountains are global biodiversity hotspots where cold environments and their associated ecological communities are predicted to be threatened by climate warming. Considerable research attention has been devoted to understanding the ecological effects of alpine glacier and snowfield recession. However, much less attention has been given to identifying climate refugia in mountain ecosystems where present-day environmental conditions will be maintained, at least in the near-term, as other habitats change. Around the world, montane communities of microbes, animals, and plants live on, adjacent to, and downstream of rock glaciers and related cold rocky landforms (CRL). These geomorphological features have been overlooked in …

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From Ideas To Items: A Primer On The Development Of Ordered Multiple-Choice Items For Investigating The Progression Of Learning In Higher Education Stem, Katherine Lazenby, Morgan E. Balabanoff, Nicole M. Becker, Alena Moon, Jack Barbera Jan 2021

From Ideas To Items: A Primer On The Development Of Ordered Multiple-Choice Items For Investigating The Progression Of Learning In Higher Education Stem, Katherine Lazenby, Morgan E. Balabanoff, Nicole M. Becker, Alena Moon, Jack Barbera

Chemistry Faculty Publications and Presentations

Identifying effective methods of assessment and developing robust assessments are key areas of research in chemistry education. This research is needed to evaluate instructional innovations and curricular reform. In this primer, we advocate for the use of a type of assessment, ordered multiple-choice (OMC), across postsecondary chemistry. OMC assessments are grounded in a developmental perspective, which treats students’ knowledge as developing in sophistication over time. This is in contrast to a dichotomous perspective, which asserts that students’ knowledge is either aligned or misaligned with scientifically accepted knowledge. By drawing on a developmental perspective, OMC assessments offer insights into student understanding …

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Curriculum Change 2021-2022, Portland State University Jan 2021

Curriculum Change 2021-2022, Portland State University

Bulletin & Curriculum Change Documents

No abstract provided.

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Bulletin: General Catalog Issue 2021-2022, Portland State University Jan 2021

Bulletin: General Catalog Issue 2021-2022, Portland State University

Bulletin & Curriculum Change Documents

No abstract provided.

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How Blockchain And Ai Enable Personal Data Privacy And Support Cybersecurity, Stanton Heister, Kristi Yuthas Jan 2021

How Blockchain And Ai Enable Personal Data Privacy And Support Cybersecurity, Stanton Heister, Kristi Yuthas

Business Faculty Publications and Presentations

Recent increases in security breaches and digital surveillance highlight the need for improved privacy and security, particularly over users’ personal data. Advances in cybersecurity and new legislation promise to improve data protection. Blockchain and distributed ledger technologies provide novel opportunities for protecting user data through decentralized identity and other privacy mechanisms. These systems can allow users greater sovereignty through tools that enable them to own and control their own data. Artificial intelligence provides further possibilities for enhancing system and user security, enriching data sets, and supporting improved analytical models.

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Ecohydrology Of Epiphytes: Modelling Water Balance, Cam Photosynthesis, And Their Climate Impacts, Gretta Miller, Samantha Hartzell, Amilcare Porporato Jan 2021

Ecohydrology Of Epiphytes: Modelling Water Balance, Cam Photosynthesis, And Their Climate Impacts, Gretta Miller, Samantha Hartzell, Amilcare Porporato

Civil and Environmental Engineering Faculty Publications and Presentations

Epiphytes are aerial plants, often characterized by CAM (crassulacean acid metabolism) photosynthesis, which make up a significant portion of the biomass in some rainforests. Their unique characteristics have not yet been included in ecohydrological models, and their potential impact on local hydrometeorology is largely unexplored. This work introduces a water balance model for epiphytes, which adapts the soil‐plant‐atmosphere continuum model to represent a plant system without soil and couples it to the Photo3 photosynthesis model, which includes CAM photosynthesis. The model, which is parameterized with field data of Guzmania monostachia, accurately captures the observed hydraulic and photosynthetic behaviour of …

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Boolean Network Control With Ideals, Ian H. Dinwoodie Jan 2021

Boolean Network Control With Ideals, Ian H. Dinwoodie

Mathematics and Statistics Faculty Publications and Presentations

A method is given for finding controls to transition an initial state x0 to a target set in deterministic or stochastic Boolean network control models. The algorithms use multivariate polynomial algebra. Examples illustrate the application.

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Simulations Of Single- And Two-Tone Tm-Doped Optical Fiber Laser Amplifiers, Tathagata Goswami, J. Grosek, Jay Gopalakrishnan Jan 2021

Simulations Of Single- And Two-Tone Tm-Doped Optical Fiber Laser Amplifiers, Tathagata Goswami, J. Grosek, Jay Gopalakrishnan

Mathematics and Statistics Faculty Publications and Presentations

This work uses numerical simulations of a thulium-doped optical fiber amplifier to predict various performance characteristics such as peak temperatures, expected output powers and efficiencies, presence of amplified spontaneous emission (ASE), and transverse mode instability (TMI) onset power thresholds. Single- and two-tone configurations are studied. In the latter case, the two laser sources are separated in frequency by the amount that corresponds to the peak Raman gain, and a few seed ratios at various total seed powers are examined. The goal is to provide the field with pertinent information on what is feasible for this type of amplifier.

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