Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Portland State University

Discipline
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 991 - 1020 of 8690

Full-Text Articles in Entire DC Network

The Radical Relationality Of Complex Partnerships: Community-Member Experiences In Critical Community-Based Learning, Amie Riley Aug 2023

The Radical Relationality Of Complex Partnerships: Community-Member Experiences In Critical Community-Based Learning, Amie Riley

Dissertations and Theses

Through a radical relationality within the social-ecological systems that sustain us, critical community-based learning (CBL) in higher education offers a praxis for engaging the demanding pedagogical and community challenges we face. When CBL is implemented as both a critical and sustainability pedagogy, as a strategy for social change, the relationships created by CBL partnerships have the potential to generate transformational outcomes for all partnership agents. Using a critical complexity theoretical framework, a bricolage of complexity science and critical theory, this critical qualitative study sought to understand the systemic patterns and behaviors of a community-based learning partnership by elevating community-member voices. …


Ronald E. Mcnair Scholars Program Profiles And Abstracts 2023, Motutama Sipelii Aug 2023

Ronald E. Mcnair Scholars Program Profiles And Abstracts 2023, Motutama Sipelii

McNair Symposium

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


Modeling Of Signals And Spectra: 5g And Beyond, Xianzhen Yang Aug 2023

Modeling Of Signals And Spectra: 5g And Beyond, Xianzhen Yang

Dissertations and Theses

The collection of papers addresses various aspects of spectra and signals in RF wireless systems for 5G and beyond. The first paper focuses on the nonlinear effects of amplified dual-band OFDM signals, providing a spectrum model for intermodulation and cross-modulation. The second paper extends this analysis beyond bandwidth restrictions, enabling accurate prediction of amplified dual-band spectrum. The third paper emphasizes the significance of out-of-band intermodulation products and derives an analytical expression using third-order intercept points. The fourth paper presents a unified spectrum expression for OFDM, FBMC, and F-OFDM, facilitating comparative insights into these signals. The fifth paper explores second-order intermodulation …


Phase Stability Of Lead Phosphate Apatite, Jiahong Shen, Dale Gaines Ii, S. Shahabfar, Zi Li, Dohun Kang, Sean Griesemer, Adolfo Salgado-Casanova, Tzu-Chen Liu, Yi Xia, Multiple Additional Authors Aug 2023

Phase Stability Of Lead Phosphate Apatite, Jiahong Shen, Dale Gaines Ii, S. Shahabfar, Zi Li, Dohun Kang, Sean Griesemer, Adolfo Salgado-Casanova, Tzu-Chen Liu, Yi Xia, Multiple Additional Authors

Mechanical and Materials Engineering Faculty Publications and Presentations

Recently, Cu-substituted lead apatite LK-99 was reported to have room-temperature ambientpressure superconductivity. Here we utilize density functional theory (DFT) total energy and harmonic phonon calculations to investigate the thermodynamic and dynamic stability of two lead phosphate apatites in their pure and Cu-substituted structures. Though Pb10(PO4)6O and Pb10(PO4)6(OH)2 are found to be thermodynamically stable (i.e., on the T=0K ground state convex hull), their Cu-substituted counterparts are above the convex hull. Harmonic phonon calculations reveal dynamic instabilities in all four of these structures. Oxygen vacancy formation …


Modeling And Validating Temporal Rules With Semantic Petri Net For Digital Twins, Han Liu, Xiaoyu Song, Ge Gao, Hehua Zhang, Yu-Shen Liu, Ming Gu Aug 2023

Modeling And Validating Temporal Rules With Semantic Petri Net For Digital Twins, Han Liu, Xiaoyu Song, Ge Gao, Hehua Zhang, Yu-Shen Liu, Ming Gu

Electrical and Computer Engineering Faculty Publications and Presentations

Semantic rule checking on RDFS/OWL data has been widely used in the construction industry. At present, semantic rule checking is mainly performed on static models. There are still challenges in integrating temporal models and semantic models for combined rule checking. In this paper, Semantic Petri-Net (SPN) is proposed as a novel temporal modeling and validating method, which implements the states and transitions of the Colored Petri-Net directly based on RDFS and SPARQL, and realizes two-way sharing of knowledge between domain semantic webs and temporal models in the runtime. Several cases are provided to demonstrate the possible applications in digital twins …


Water Quality Land Cover Change And Water Quality In Wetlands At The City Of Gresham, Or, Evelyn Barajas, Michael Gonzalez Aug 2023

Water Quality Land Cover Change And Water Quality In Wetlands At The City Of Gresham, Or, Evelyn Barajas, Michael Gonzalez

altREU Projects

The City of Gresham, Oregon has implemented constructed wetlands around the area as an attempt to collect, filter, and purify water from different sources such as rain, agricultural waste, and domestic waste. We focused our research on three different facilities: Columbia Slough Water Quality Facility (CSWQF), Fairview Creek Water Quality Facility, and Brookside Water Quality Facility. For each of these, we conducted tests and looked at the concentration levels for nitrogen and phosphorus nutrients such as NH3-N (ammonium), NO3-N (nitrate), TKN (total Kjeldahl nitrogen), O-PO4 (phosphate), and Total P (total phosphorus), as well as heavy metals like Total Cu (total …


Human-Modified Landscapes Driving The Global Primate Extinction Crisis, Erik Joaquín Torres-Romero, Vincent Nijman, David Fernández, Timothy M. Eppley Aug 2023

Human-Modified Landscapes Driving The Global Primate Extinction Crisis, Erik Joaquín Torres-Romero, Vincent Nijman, David Fernández, Timothy M. Eppley

Anthropology Faculty Publications and Presentations

The world's primates have been severely impacted in diverse and profound ways by anthropogenic pressures. Here, we evaluate the impact of various infrastructures and human-modified landscapes on spatial patterns of primate species richness, at both global and regional scales. We overlaid the International Union for the Conservation of Nature (IUCN) range maps of 520 primate species and applied a global 100 km2 grid. We used structural equation modeling and simultaneous autoregressive models to evaluate direct and indirect effects of six human-altered landscapes variables (i.e., human footprint [HFP], croplands [CROP], road density [ROAD], pasture lands [PAST], protected areas [PAs], and Indigenous …


Multidrug Resistance Of Escherichia Coli From Outpatient Uncomplicated Urinary Tract Infections In A Large United States Integrated Healthcare Organization, Katia J. Bruxvoort, Jennifer H. Ku, S. Bianca Salas, Cara D. Varley, Joan A. Casey, Eva Raphael, Sarah C. Robinson, Keeve E. Nachman, Bruno J. Lewin, Multiple Additional Authors Aug 2023

Multidrug Resistance Of Escherichia Coli From Outpatient Uncomplicated Urinary Tract Infections In A Large United States Integrated Healthcare Organization, Katia J. Bruxvoort, Jennifer H. Ku, S. Bianca Salas, Cara D. Varley, Joan A. Casey, Eva Raphael, Sarah C. Robinson, Keeve E. Nachman, Bruno J. Lewin, Multiple Additional Authors

OHSU-PSU School of Public Health Faculty Publications and Presentations

Background

Urinary tract infections (UTIs) cause significant disease and economic burden. Uncomplicated UTIs (uUTIs) occur in otherwise healthy individuals without underlying structural abnormalities, with uropathogenic Escherichia coli (UPEC) accounting for 80% of cases. With recent transitions in healthcare toward virtual visits, data on multidrug resistance (MDR) (resistant to ≥3 antibiotic classes) by care setting are needed to inform empiric treatment decision making.

Methods

We evaluated UPEC resistance over time by care setting (in-person vs virtual), in adults who received outpatient care for uUTI at Kaiser Permanente Southern California between January 2016 and December 2021.

Results

We included 174 185 individuals …


Exploring And Testing Wildfire Risk Decision-Making In The Face Of Deep Uncertainty, Bart R. Johnson, Alan A. Ager, Cody Evers, David Hulse, Max Nielsen-Pincus, John P. Bolte Aug 2023

Exploring And Testing Wildfire Risk Decision-Making In The Face Of Deep Uncertainty, Bart R. Johnson, Alan A. Ager, Cody Evers, David Hulse, Max Nielsen-Pincus, John P. Bolte

Environmental Science and Management Faculty Publications and Presentations

We integrated a mechanistic wildfire simulation system with an agent-based landscape change model to investigate the feedbacks among climate change, population growth, development, landowner decision-making, vegetative succession, and wildfire. Our goal was to develop an adaptable simulation platform for anticipating risk-mitigation tradeoffs in a fire-prone wildland– urban interface (WUI) facing conditions outside the bounds of experience. We describe how five social and ecological system (SES) submodels interact over time and space to generate highly variable alternative futures even within the same scenario as stochastic elements in simulated wildfire, succession, and landowner decisions create large sets of unique, path-dependent futures for …


Evaluating How Well Active Fault Mapping Predicts Earthquake Surface-Rupture Locations, Chelsea Scott, Ramon Arrowsmith, Rachel Adam, Christopher Madugo, Joseph Powell, John Ford, Brian Gray, Ashley Streig, Multiple Additional Authors Aug 2023

Evaluating How Well Active Fault Mapping Predicts Earthquake Surface-Rupture Locations, Chelsea Scott, Ramon Arrowsmith, Rachel Adam, Christopher Madugo, Joseph Powell, John Ford, Brian Gray, Ashley Streig, Multiple Additional Authors

Geology Faculty Publications and Presentations

Earthquake surface-fault rupture location uncertainty is a key factor in fault displacement hazard analysis and informs hazard and risk mitigation strategies. Geologists often predict future rupture locations from fault mapping based on the geomorphology interpreted from remote-sensing data sets. However, surface processes can obscure fault location, fault traces may be mapped in error, and a future rupture may not break every fault trace. We assessed how well geomorphology-based fault mapping predicted surface ruptures for seven earthquakes: 1983 M 6.9 Borah Peak, 2004 M 6.0 Parkfield, 2010 M 7.2 El Mayor–Cucapah, 2011 M 6.7 Fukushima-Hamadori, 2014 M 6.0 South Napa, 2016 …


Low Internal Air Space In Plants With Crassulacean Acid Metabolism May Be An Anatomical Spandrel, Alistair Leverett, Anne Borland, Emma Inge, Samantha Hartzell Aug 2023

Low Internal Air Space In Plants With Crassulacean Acid Metabolism May Be An Anatomical Spandrel, Alistair Leverett, Anne Borland, Emma Inge, Samantha Hartzell

Civil and Environmental Engineering Faculty Publications and Presentations

Crassulacean Acid Metabolism (CAM) is a photosynthetic adaptation found in at least 38 plant families. Typically, the anatomy of CAM plants is characterised by large photosynthetic cells and a low percentage of leaf volume comprised of internal air space (% IAS). It has been suggested that reduced mesophyll conductance (gm) arising from low % IAS benefits CAM plants by preventing the movement of CO2 out of cells and ultimately minimising leakage of CO2 from leaves into the atmosphere during day-time decarboxylation. Here, we propose that low % IAS does not provide any adaptive benefit to …


A Study On The Gaseous Radionuclide Dispersion In The Highway Across Urban Blocks: Effects Of The Urban Morphology, Roadside Vegetation And Leakage Location, Rui Jia, Jianzhi Yang, Xiaowei Zhu, Fusuo Xu, Liping Wang Aug 2023

A Study On The Gaseous Radionuclide Dispersion In The Highway Across Urban Blocks: Effects Of The Urban Morphology, Roadside Vegetation And Leakage Location, Rui Jia, Jianzhi Yang, Xiaowei Zhu, Fusuo Xu, Liping Wang

Mechanical and Materials Engineering Faculty Publications and Presentations

Spent fuel is a used nuclear waste that poses a great hazard to human body and the environment. In this work, the dispersion of gaseous radionuclides from the highway to downstream urban is simulated using CFD based on a hypothetical spent fuel transport accident, with focus on the effects of urban morphology, roadside vegetation and leakage location. The velocity field, TKE (turbulent kinetic energy) distribution and radionuclide concentration under different conditions are carefully explored. The results show that the dispersion of radionuclides is greatly influenced by the velocity field and TKE distribution. The health risk to the residents of sparse …


Quantifying Damages To Soil Health And Emissions From Land Development In The State Of Illinois (Usa), Elena A. Mikhailova, Hamdi A. Zurqani, Zhenbang Hao, Mark A. Schlautman, Gregory C. Post, George B. Shepherd, Christopher C. Post, Renee M. Dixon Aug 2023

Quantifying Damages To Soil Health And Emissions From Land Development In The State Of Illinois (Usa), Elena A. Mikhailova, Hamdi A. Zurqani, Zhenbang Hao, Mark A. Schlautman, Gregory C. Post, George B. Shepherd, Christopher C. Post, Renee M. Dixon

Geography Faculty Publications and Presentations

The concept of soil health is increasingly being used as an indicator for sustainable soil management and even includes legislative actions. Current applications of soil health often lack geospatial and monetary analyses of damages (e.g., land development), which can degrade soil health through loss of carbon (C) and productive soils. This study aims to evaluate the damages to soil health (e.g., soil C, the primary soil health indicator) attributed to land developments within the state of Illinois (IL) in the United States of America (USA). All land developments in IL can be associated with damages to soil health, with 13,361.0 …


Rift-Induced Disruption Of Cratonic Keels Drives Kimberlite Volcanism, Thomas M. Gernon, Stephen M. Jones, Sascha Brune, Thea K. Hincks, Martin Palmer, John C. Schumacher, Rebecca M. Primiceri, Matthew Field, William L. Griffin, Suzanne Y. O'Reilly, Derek Keir, Christopher J. Spencer, Andrew S. Merdith, Anne Glerum Jul 2023

Rift-Induced Disruption Of Cratonic Keels Drives Kimberlite Volcanism, Thomas M. Gernon, Stephen M. Jones, Sascha Brune, Thea K. Hincks, Martin Palmer, John C. Schumacher, Rebecca M. Primiceri, Matthew Field, William L. Griffin, Suzanne Y. O'Reilly, Derek Keir, Christopher J. Spencer, Andrew S. Merdith, Anne Glerum

Geology Faculty Publications and Presentations

Kimberlites are volatile-rich, occasionally diamond-bearing magmas that have erupted explosively at Earth’s surface in the geologic past1,2,3. These enigmatic magmas, originating from depths exceeding 150 km in Earth’s mantle1, occur in stable cratons and in pulses broadly synchronous with supercontinent cyclicity4. Whether their mobilization is driven by mantle plumes5 or by mechanical weakening of cratonic lithosphere4,6 remains unclear. Here we show that most kimberlites spanning the past billion years erupted about 30 million years (Myr) after continental breakup, suggesting an association with rifting processes. Our dynamical …


How Unequal Access To Personal And Professional Networks Impacts Success Among Construction Apprentices, Cameron Elliot Arnold Jul 2023

How Unequal Access To Personal And Professional Networks Impacts Success Among Construction Apprentices, Cameron Elliot Arnold

Dissertations and Theses

The construction industry is still primarily white male dominated, and while there is significant research on gendered experiences in the trades, there is not research on experiences and attitudes towards support that occurs outside of the trades across gender and other intersectional identities. My study aims to start filling the gap and answer the questions: How does access to personal and professional networks impact success among Oregon apprentices? How is access to and attitudes towards receiving support impacted by gender and race? To answer these questions this study uses qualitative interviews of Oregon apprentices who completed or terminated in 2018-2019. …


Communion Anthropoid, Joshua Stanek Jul 2023

Communion Anthropoid, Joshua Stanek

Dissertations and Theses

In National Lampoon's Vegas Vacation, a man of good will offers all he has to a dear brother-in-law--recognizing the snakes he keeps as toys, the camper, the stones, dirt, and arid shrubbery are likewise dear to him. They go out to the desert at night and dig shallow holes, seemingly at random. Their imprecision is surprisingly fruitful. Imagine the constellation they made for the stars. In Communion Anthropoid, I am digging shallow holes in the dark with a mind to unearth what I believe I have lost. The dearness, I suppose. These poems vary in form from eight …


Confronting Web3 Technology: Opportunities, Challenges And Community Formation, Christopher-John Rogers Jul 2023

Confronting Web3 Technology: Opportunities, Challenges And Community Formation, Christopher-John Rogers

Dissertations and Theses

The emergence of blockchain technology created an entire industry of innovative new digital assets--or tokens--and diverse new fields of expertise founded on ideological aspirations of a new World Wide Web that reimagines digital value transfer through decentralization and disintermediation. Experimentation in the so-called "Web3" industry produces rich new fields of ethnographic study revealing the experiences of diverse individuals navigating novel technological capabilities which give way to new avenues of identity formation, community building, and ecosystem creation. These exciting new endeavors come with difficult challenges threatening the realization of ambitious visions for digital futures. Ethnographic research conducted through discourse analysis, participant …


Disentangling Groundwater Dynamics At Oregon's Mckenzie River Headwaters, Taylor Nicole Salazar Jul 2023

Disentangling Groundwater Dynamics At Oregon's Mckenzie River Headwaters, Taylor Nicole Salazar

Dissertations and Theses

Widespread mountain snowpack declines have been occurring across the western United States over the last century, and are increasing in duration and severity, with several record-breaking low-snowpack years in the last decade. In the Pacific Northwest, summer streamflow is largely a result of melting snow and groundwater discharge, as summers are typically dry and warm in this Mediterranean bioclimate, thus making spring-fed rivers critical for regional water resources. However, current trends and predictions in hydroclimate modeling indicate spring-fed rivers will experience reduced summer discharge driven by the increasingly larger impact of anthropogenic climate change (warming) on (decreased) mountain snowpack. A …


Radical Urban Natures: Mitigating Urban Heat With Nature-Based Techniques In Portland, Oregon, Heather Day-Melgar Jul 2023

Radical Urban Natures: Mitigating Urban Heat With Nature-Based Techniques In Portland, Oregon, Heather Day-Melgar

Dissertations and Theses

Anthropogenic rising heat associated with climatic changes in the built environment has become a serious global issue. The built environment is often comprised of impermeable, paved surfaces, lack of vegetation to make way for development, tree removal, and loss or alteration of urban waterways, which leads to a degraded ecosystem for humans and non-human life, and less of an ability for carbon capture, all of which contribute to higher urban temperatures. This alteration of the existing natural environment leads to populations often unable to conceptualize that a built environment is still an ecosystem, and restoration is possible and necessary for …


A Daily Investigation Of The Recovery Paradox: Examining The Dynamic Interplay Of Workload, Recovery Experiences, And Microbreaks, Morgan Rose Taylor Jul 2023

A Daily Investigation Of The Recovery Paradox: Examining The Dynamic Interplay Of Workload, Recovery Experiences, And Microbreaks, Morgan Rose Taylor

Dissertations and Theses

Research has highlighted the importance of recovery from work stress during non-work time for employee health and wellbeing. Building on the recovery from work stress literature, this study examines the recovery paradox which suggests that employees may recover from work demands the least when they need it the most. Therefore, the purpose of this study is to shed light on the mechanisms underlying the recovery paradox. Specifically, this study examined whether a common work stressor, workload in the morning, is indirectly related to poorer recovery experiences in the evening through negative states at the end of workday. Furthermore, this study …


Assessing The Performance Of Exchange-Correlation Functionals On Lattice Constants Of Binary Solids At Room Temperature Within The Quasiharmonic Approximation, Xiaofei Shao, Peitao Liu, Cesare Franchini, Yi Xia, Jiangang He Jul 2023

Assessing The Performance Of Exchange-Correlation Functionals On Lattice Constants Of Binary Solids At Room Temperature Within The Quasiharmonic Approximation, Xiaofei Shao, Peitao Liu, Cesare Franchini, Yi Xia, Jiangang He

Mechanical and Materials Engineering Faculty Publications and Presentations

The exchange-correlation functional is at the core of density functional theory (DFT) and determines the accuracy of DFT in describing the interactions among electrons/ions in solids and molecules. The strongly constrained and appropriately normed functional (SCAN) and its derivatives, regularized SCAN (rSCAN) and regularized-restored SCAN (r2SCAN), are particularly promising due to their remarkable overall accuracy in the description of various properties while retaining a high computational efficiency as compared to hybrid functionals. However, an exhaustive assessment on the performance of these functionals in predicting the finite-temperature lattice constant of solids is still lacking. Here, we systematically study the room-temperature lattice …


Compensation Of Seeding Bias For Particle Tracking Velocimetry In Turbulent Flows, Thomas Barois, Bianca Viggiano, Thomas Basset, Raúl Bayoán Cal, Romain Volk, Mathieu Gibert, Mickael Bourgoin Jul 2023

Compensation Of Seeding Bias For Particle Tracking Velocimetry In Turbulent Flows, Thomas Barois, Bianca Viggiano, Thomas Basset, Raúl Bayoán Cal, Romain Volk, Mathieu Gibert, Mickael Bourgoin

Mechanical and Materials Engineering Faculty Publications and Presentations

When a fluid in turbulent motion is tagged by a nonuniform concentration of ideal tracers, the mean velocity of the tracers may not match with the mean velocity of the fluid flow. This implies that conventional particle tracking velocimetry will not produce the mean flow of a turbulent flow unless the particle seeding is homogeneous. In this work, we consider the problem of mean flow estimation from a set of particle tracks obtained in a situation of nonhomogeneous seeding. To compensate the bias caused by the nonhomogeneous particle seeding, we propose a modified particle tracking velocimetry method. This method is …


Systematic Characterization Of Power Side Channel Attacks For Residual And Added Vulnerabilities, Aurelien Tchoupou Mozipo Jul 2023

Systematic Characterization Of Power Side Channel Attacks For Residual And Added Vulnerabilities, Aurelien Tchoupou Mozipo

Dissertations and Theses

Power Side Channel Attacks have continued to be a major threat to cryptographic devices. Hence, it will be useful for designers of cryptographic systems to systematically identify which type of power Side Channel Attacks their designs remain vulnerable to after implementation. It’s also useful to determine which additional vulnerabilities they have exposed their devices to, after the implementation of a countermeasure or a feature. The goal of this research is to develop a characterization of power side channel attacks on different encryption algorithms' implementations to create metrics and methods to evaluate their residual vulnerabilities and added vulnerabilities. This research studies …


In Their Words: Prospective Teachers' Experiences As A Context For Investigating Their Views Of Authority In A Mathematics Classroom, Brenda Lynn Rosencrans Jul 2023

In Their Words: Prospective Teachers' Experiences As A Context For Investigating Their Views Of Authority In A Mathematics Classroom, Brenda Lynn Rosencrans

Dissertations and Theses

Mathematics teacher educators enact inquiry-based preparatory courses with the underlying expectation that their students (prospective teachers) will take ownership (authority) of their mathematical learning through sharing their ideas and collaboratively discussing the reasonableness of their shared ideas. Yet, prospective teachers' expectations are often not yet in alignment with those of mathematics teacher educators, instead they enter these courses expecting their instructors to provide clear examples and directions for how to solve mathematics problems. This project investigates this dynamic through an authority lens, seeking to understand and characterize different views of authority prospective teachers hold and the impact these views have …


Quantifying Uncertainties In Direct-Numerical-Simulation Statistics Due To Wall-Normal Numerics And Grids, Peng E. S. Chen, Xiaowei Zhu, Yipeng Shi, Xiang I. A. Yang Jul 2023

Quantifying Uncertainties In Direct-Numerical-Simulation Statistics Due To Wall-Normal Numerics And Grids, Peng E. S. Chen, Xiaowei Zhu, Yipeng Shi, Xiang I. A. Yang

Mechanical and Materials Engineering Faculty Publications and Presentations

This paper takes the perspective of a user of direct-numerical-simulation (DNS) data and quantifies the uncertainties in DNS statistics for plane channel flows. We focus on high-order statistics, such as skewness, kurtosis, and viscous dissipation, and quantify the uncertainties due to wall-normal numerics and grids while minimizing the sampling error and the discretization error in the wall-parallel directions. Two grid distributions and four discretization methods are considered, which are representative of the existing DNSs. Our results show that the available DNS data contain at least a 7% uncertainty in the computed mean viscous dissipation in the buffer layer. Moreover, since …


Load Effects Of Truck Platooning On Existing Bridges In Oregon, Patricia Oleson Jul 2023

Load Effects Of Truck Platooning On Existing Bridges In Oregon, Patricia Oleson

Civil and Environmental Engineering Master's Project Reports

Truck Platooning (TP) involves managing multiple trucks closely together to reduce aerodynamic drag. While TP offers benefits such as fuel savings, emission reductions, and enhanced safety, it raises concerns for existing infrastructure. This study reviews literature on TP and conducts bridge analyses comparing representative truck platoon configurations allowed under Oregon law with current truck loadings. It also explores the effects of truck head spacing and bridge span lengths, utilizing the research results to calculate rating factors using real-world case studies. The objective is to identify truck platoon configurations that may exceed acceptable load levels for Oregon bridges. The findings will …


Distributed Deep Learning Optimization Of Heat Equation Inverse Problem Solvers, Zhuowei Wang, Le Yang, Haoran Lin, Genping Zhao, Zixuan Liu, Xiaoyu Song Jul 2023

Distributed Deep Learning Optimization Of Heat Equation Inverse Problem Solvers, Zhuowei Wang, Le Yang, Haoran Lin, Genping Zhao, Zixuan Liu, Xiaoyu Song

Electrical and Computer Engineering Faculty Publications and Presentations

The inversion problem of partial differential equation plays a crucial role in cyber-physical systems applications. This paper presents a novel deep learning optimization approach to constructing a solver of heat equation inversion. To improve the computational efficiency in large-scale industrial applications, data and model parallelisms are incorporated on a platform of multiple GPUs. The advanced Ring-AllReduce architecture is harnessed to achieve an acceleration ratio of 3.46. Then a new multi-GPUs distributed optimization method GradReduce is proposed based on Ring-AllReduce architecture. This method optimizes the original data communication mechanism based on mechanical time and frequency by introducing the gradient transmission scheme …


Lift Force Analysis For An Electrodynamic Wheel Maglev Vehicle, Colton W. Bruce, Jonathan Bird, Matthew K. Grubbs Jul 2023

Lift Force Analysis For An Electrodynamic Wheel Maglev Vehicle, Colton W. Bruce, Jonathan Bird, Matthew K. Grubbs

Electrical and Computer Engineering Faculty Publications and Presentations

This paper used an analytic based 3-D second order vector potential model to study the vertical dynamic force ripple and dynamic airgap height change when using a one pole-pair electrodynamic wheel (EDW) maglev vehicle. A one-pole pair EDW creates the lowest lift specific power; however transient finite element analysis (FEA) also shows that the one pole-pair EDW will create a large oscillating vertical force when maintaining a static airgap height. A dynamically coupled eddy current model was used to confirm that when the airgap length is allowed to change with time then an increase in vertical airgap creates a large …


Modeling Cyanotoxin Production, Fate, And Transport In Surface Water Bodies Using Ce-Qual-W2, Bernadel Rose Hintz Garstecki, Scott A. Wells Jul 2023

Modeling Cyanotoxin Production, Fate, And Transport In Surface Water Bodies Using Ce-Qual-W2, Bernadel Rose Hintz Garstecki, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

Cyanobacteria 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 are expected to increase the occurrence of cyanobacteria, and it is vital that we protect our drinking water supplies and natural water resources. Modeling the production, fate, and transport of these toxins is an important step in limiting exposure to them and evaluating management strategies to mitigate their impact. The research provided here offers an overview of some of the main cyanotoxins of concern and presents preliminary models for the transport and …


Cu2o Heterojunction Solar Cell With Photovoltaic Properties Enhanced By A Ti Buffer Layer, Binghao Wang, Zhiqiang Chen, Feng Zhao Jul 2023

Cu2o Heterojunction Solar Cell With Photovoltaic Properties Enhanced By A Ti Buffer Layer, Binghao Wang, Zhiqiang Chen, Feng Zhao

Center for Electron Microscopy and Nanofabrication Publications and Presentations

In this study, semiconductor oxide cuprite (Cu2O) and indium tin oxide (ITO) heterojunction solar cells with and without a 10 nm thick titanium (Ti) thin film as the buffer layer were fabricated and characterized for comparison. The Cu2O film was formed by low-cost electrodeposition, and Ti and ITO layers were deposited on a glass substrate by sputtering. The interfacial microstructures, surface topology, and electrical and photovoltaic properties of both solar cells were investigated. The test results showed that the Ti buffer layer changed the surface morphology, resistivity, and contact potential of the electrodeposited Cu2O film. With these changes, the photovoltaic …