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Articles 2881 - 2910 of 6918
Full-Text Articles in Entire DC Network
Secondary Analysis Of Concussion Data, Martin Zwick, Stephanie Kolakowsky-Hayner, Nancy Carney, Maya Balamane, Tracie Nettleton, D. Wright
Secondary Analysis Of Concussion Data, Martin Zwick, Stephanie Kolakowsky-Hayner, Nancy Carney, Maya Balamane, Tracie Nettleton, D. Wright
Complex Systems Faculty Publications and Presentations
Clinical studies are expensive & time-consuming. Typically in these studies specific hypotheses are subjected to confirmatory test. Yet the data may harbor evidence of unanticipated relations between variables. It is thus desirable to subject the data to secondary analyses in the hope of discovering novel & valuable associations. Exploratory analysis, however, is tentative: findings should be replicated in new data. This presentation reports some secondary analyses on concussion data. Data mining on 2 datasets will be discussed, & some unexpected findings reported. The analyses use reconstructability analysis (RA), a probabilistic graphical modeling method implemented in the Occam software package developed …
Using Transects To Understand Cyanobacterial Blooms, John Rueter
Using Transects To Understand Cyanobacterial Blooms, John Rueter
Environmental Science and Management Faculty Publications and Presentations
Presentation focuses on Toxic algae (and cyanobacteria) and on short-term mitigation:
- Monitoring
- Possible approaches
Effects Of Antibiotic Mixtures Across Marine Intertidal Trophic Levels: Examining Environmentally-Relevant Contaminant Concentrations, Jaclyn Rebecca Teixeira
Effects Of Antibiotic Mixtures Across Marine Intertidal Trophic Levels: Examining Environmentally-Relevant Contaminant Concentrations, Jaclyn Rebecca Teixeira
Dissertations and Theses
Approximately 48% of Americans use prescription drugs within each 30-day period, and there are signs this trend is increasing. Although many studies track pharmaceuticals’ fates in contaminating waterways, only fairly recent efforts have examined the potential impacts of these drugs on non-target organisms. The antibiotics sulfamethoxazole and trimethoprim, often prescribed together to treat bacterial infections, have been detected worldwide in marine and estuarine environments at concentrations up to 700-800 ng/L each. Toxic effects of these drugs have been identified in freshwater organisms, with synergistic effects observed in short-term studies of mixtures of the two; however, little research has examined possible …
The Edge Of The Known Is Infinite: Original Contributions In Undergraduate Research (Full Issue)
The Edge Of The Known Is Infinite: Original Contributions In Undergraduate Research (Full Issue)
PSU McNair Scholars Online Journal
No abstract provided.
A Measurement System For Science And Engineering Research Center Performance Evaluation, Elizabeth Carole Gibson
A Measurement System For Science And Engineering Research Center Performance Evaluation, Elizabeth Carole Gibson
Dissertations and Theses
This research provides performance metrics for cooperative research centers that enhance translational research formed by the partnership of government, industry and academia. Centers are part of complex ecosystems that vary greatly in the type of science conducted, organizational structures and expected outcomes. The ability to realize their objectives depends on transparent measurement systems to assist in decision making in research translation.
A generalizable, hierarchical decision model that uses both quantitative and qualitative metrics is developed based upon program goals. Mission-oriented metrics are used to compare the effectiveness of the cooperative research centers through case studies.
The US National Science Foundation …
Image Stitching: Handling Parallax, Stereopsis, And Video, Fan Zhang
Image Stitching: Handling Parallax, Stereopsis, And Video, Fan Zhang
Dissertations and Theses
Panorama stitching increases the field of view in an image by assembling multiple views together. Traditional stitching techniques are proven to be effective only when dealing with parallax-free monocular images. Many challenges that remain unsolved in the stitching research area include how to stitch monocular images with large parallax, how to stitch stereoscopic images to maintain their stereoscopic consistency and original disparity distribution, and how to create panoramic videos with temporally coherent content. To provide more powerful stitching techniques with more universality, we first develop a parallax-tolerant image stitching technique. With the help of it, we then effectively extend the …
The Application Of Electrochemical Impedance Spectroscopy To Immediately Diagnose The Protective Quality Of Coatings On Artistic And Architectural Metalwork, Kathryn Nicole Hosbein
The Application Of Electrochemical Impedance Spectroscopy To Immediately Diagnose The Protective Quality Of Coatings On Artistic And Architectural Metalwork, Kathryn Nicole Hosbein
Dissertations and Theses
Corrosion is a spontaneous process that causes irreversible damage to nearly all metals, which has world-wide implications for architectural and artistic metalwork, such as bridges, buildings, airplanes and sculptures. Protective coatings such as wax, paint, or polymeric clear coatings are used to prolong the lifetime of metals such as steel and bronze. Unfortunately, these coatings fail over time due to oxidative damage by UV rays and by failure to exclude water that can carry salts and pollutants that cause corrosion of the underlying substrate. The current method of coating assessment is visual inspection but when coating failure is detected at …
The Impact Of Innovation: New Frontiers In Undergraduate Research (Full Issue)
The Impact Of Innovation: New Frontiers In Undergraduate Research (Full Issue)
PSU McNair Scholars Online Journal
No abstract provided.
Exploring Transformation: An Analysis Of Culture, Identity & Borderlands (Full Issue)
Exploring Transformation: An Analysis Of Culture, Identity & Borderlands (Full Issue)
PSU McNair Scholars Online Journal
No abstract provided.
Hydrogeochemical Evaluation Of The Uinta Formation And Green River Formation, Piceance Creek Basin, Northwestern Colorado, Usa, Megan E. Masterson
Hydrogeochemical Evaluation Of The Uinta Formation And Green River Formation, Piceance Creek Basin, Northwestern Colorado, Usa, Megan E. Masterson
Dissertations and Theses
The Piceance Creek Basin in northwestern Colorado contains extensive oil shale deposits that produce natural gas and which could potentially yield ~1.5 trillion barrels of shale oil. However, much of the oil shale lies at depths too great for traditional mining practices and various innovative approaches for in situ conversion of kerogen to oil have been proposed. A firm understanding of the existing hydrogeochemistry is needed as resulting mineralogical changes or rock-fluid reactions may affect rock porosity and permeability. Using an existing database complied by the USGS, the water chemistry of 267 surface and groundwater samples in the Piceance Creek …
Comparing Sanitation Delivery Modalities In Urban Informal Settlement Schools: A Randomized Trial In Nairobi, Kenya, Kate Bohnert, Anna N. Chard, Alex Mwaki, Amy E., Kirby, Richard Muga, Corey L. Nagel, Evan A. Thomas, Matthew C. Freeman
Comparing Sanitation Delivery Modalities In Urban Informal Settlement Schools: A Randomized Trial In Nairobi, Kenya, Kate Bohnert, Anna N. Chard, Alex Mwaki, Amy E., Kirby, Richard Muga, Corey L. Nagel, Evan A. Thomas, Matthew C. Freeman
Mechanical and Materials Engineering Faculty Publications and Presentations
The provision of safely managed sanitation in informal settlements is a challenge, especially in schools that require durable, clean, sex-segregated facilities for a large number of children. In informal settlements in Nairobi, school sanitation facilities demand considerable capital costs, yet are prone to breakage and often unhygienic. The private sector may be able to provide quality facilities and services to schools at lower costs as an alternative to the sanitation that is traditionally provided by the government. We conducted a randomized trial comparing private sector service delivery (PSSD) of urine-diverting dry latrines with routine waste collection and maintenance and government …
Technology Trajectory Mapping Using Data Envelopment Analysis: The Ex-Ante Use Of Disruptive Innovation Theory On Flat Panel Technologies, Dong-Joon Lim, Timothy R. Anderson
Technology Trajectory Mapping Using Data Envelopment Analysis: The Ex-Ante Use Of Disruptive Innovation Theory On Flat Panel Technologies, Dong-Joon Lim, Timothy R. Anderson
Engineering and Technology Management Faculty Publications and Presentations
In this paper, we propose a technology trajectory mapping approach using Data Envelopment Analysis (DEA) that scrutinizes technology progress patterns from multidimensional perspectives. Literature reviews on technology trajectory mappings have revealed that it is imperative to identify key performance measures that can represent different value propositions and then apply them to the investigation of technology systems in order to capture indications of the future disruption. The proposed approach provides a flexibility not only to take multiple characteristics of technology systems into account but also to deal with various tradeoffs among technology attributes by imposing weight restrictions in the DEA model. …
2016 Columbia River Flowering Rush Survey, Rich Miller, Mark D. Sytsma
2016 Columbia River Flowering Rush Survey, Rich Miller, Mark D. Sytsma
Center for Lakes and Reservoirs Publications and Presentations
Flowering rush (Butomus umbellatus L.) early detection surveys were conducted in Lake Umatilla during the summer of 2016. Flowering rush is a Class A Noxious Weed in Washington State due to its aggressive nature, ecological and economic impacts, and limited distribution. Dense stands can outcompete native riparian plants, interfere with boating and fishing, and impede irrigation flows. Flowering rush has been reported in eight Washington counties (WSDA 2016) including a large infestation detected during 2008 in the Yakima River, Benton County. Several pioneering populations have since been detected further downstream in Lake Wallula and Lake Umatilla on the Columbia River …
Scientific Engagement At Fda: A Report To The Fda Science Board From The Scientific Engagement Subcommittee, Anthony Bahinski, Maria C. Friere, Mark R. Mclellan, Bruce M. Psaty, Dan M. Roden, Scott J. Steele
Scientific Engagement At Fda: A Report To The Fda Science Board From The Scientific Engagement Subcommittee, Anthony Bahinski, Maria C. Friere, Mark R. Mclellan, Bruce M. Psaty, Dan M. Roden, Scott J. Steele
Biology Faculty Publications and Presentations
Maintaining active interactions with the broad external scientific community is vital for FDA to fulfill its expanding public health mission. It is essential for the Agency to be well positioned to address emerging areas of regulatory science and rapidly advancing technologies.
Scientific engagement also helps FDA accomplish its mission by increasing awareness of FDA’s responsibilities and helping with the Agency’s critical recruitment and succession planning needs. FDA uses a range of mechanisms for scientific exchange. The Subcommittee was charged with considering:
a. how FDA can improve its interface with the outside scientific community, particularly regarding public-private partnerships (PPPs) and fellowship …
Systems Thinking In The Forest Service: A Framework To Guide Practical Application For Social-Ecological Management In The Enterprise Program, Megan Kathleen Kmon
Systems Thinking In The Forest Service: A Framework To Guide Practical Application For Social-Ecological Management In The Enterprise Program, Megan Kathleen Kmon
Dissertations and Theses
The U.S. Forest Service (USFS) Enterprise Program (EP), which provides fee-for-service consulting services to the USFS, is interested in integrating systems thinking into its service offerings. Despite there being several excellent sources on the range and diversity of systems thinking, no single framework exists that thoroughly yet concisely outlines what systems thinking is along with its deep history, theoretical tenets, and soft and hard approaches. This thesis is an attempt to create such a framework, aimed specifically at practical application in a land management agency, through literature synthesis injected with original analysis. The usefulness of the framework is then tested …
To Disappear, Rachel Chenven Powers
To Disappear, Rachel Chenven Powers
Dissertations and Theses
This is a selection of linked lyric essays, covering explorations of memory, experience, nature, transcendence, insignificance, orientation, boredom, privilege, vocation, and more.
Congestion Modeling And Mitigation In The National Airspace System, David Lovell
Congestion Modeling And Mitigation In The National Airspace System, David Lovell
PSU Transportation Seminars
Dr. Lovell will talk about three projects funded by NASA and the FAA, addressing congestion in the National Airspace System. Dr. Lovell's team developed diffusion-based queuing models of individual airports that could support better building blocks for network-wide congestion models. The advantage of the new models is their flexibility with respect to input distributions. In a study for the FAA, Dr. Lovell's team developed day-of-operations collaboration "languages" suitable for the FAA and individual carriers in order to collectively manage expected airspace disruptions. Finally, he will discuss a study on predictability in the airspace, with a focus on scheduled block times.
Development Of The Idaho Statewide Travel Demand Model Trip Matrices Using Cell Phone Od Data And Origin Destination Matrix Estimation, Ben Stabler
PSU Transportation Seminars
As part of the initial phase of development for the Idaho Statewide Travel Demand Model, Parsons Brinckerhoff developed a base year auto and truck trip matrix using AirSage cell phone OD data, a statewide network in Cube, traffic counts, and origin-destination matrix estimation (ODME) procedures. To begin, the 4000+ statewide zone system was aggregated into a 700 super zone system for collecting the cell phone OD data. Next, the cell phone data was collected for the month of September 2013 for the following market segments: Average weekday resident HBW, HBO, NHB, and visitor NHB trips. The cell phone trips were …
Understanding The Links Between Cyanobacteria Physiology And Hydrodynamics May Help Find Adaption Strategies For Toxic Blooms, John Rueter
Environmental Science and Management Faculty Publications and Presentations
Even though we are managing lakes to decrease algal blooms overall, harmful algal blooms seem to be showing up more and more frequently. Although the word “blooms” connotes dominance and rapid growth, dangerous accumulations of cyanobacteria can occur because of combinations of physiological advantages and particular weather and hydrodynamic conditions. I am particularly interested in specific conditions that might favor Aphanizomenon versus those that might favor Microcystis in Upper Klamath and Agency Lakes. Aphanizomenon is a nuisance and large blooms can lead to oxygen depletion and fish deaths. Microcystis can both be a nuisance and is toxic. The comparison of …
Faculty Senate Monthly Packet October 2016, Portland State University Faculty Senate
Faculty Senate Monthly Packet October 2016, Portland State University Faculty Senate
Faculty Senate Monthly Packets
The October 2016 Monthly packet includes the October agenda and appendices and the Faculty Senate minutes and attachments from the meeting held June 1, 2016.
Glaciers In Equilibrium, Mcmurdo Dry Valleys, Antarctica, Andrew G. Fountain, Hassan J. Basagic, Spencer Niebuhr
Glaciers In Equilibrium, Mcmurdo Dry Valleys, Antarctica, Andrew G. Fountain, Hassan J. Basagic, Spencer Niebuhr
Geology Faculty Publications and Presentations
The McMurdo Dry Valleys are a cold, dry polar desert and the alpine glaciers therein exhibit small annual and seasonal mass balances, often
Modeling The Thickness Of Perennial Ice Covers On Stratified Lakes Of The Taylor Valley, Antarctica, Maciej K. Obryk, Peter T. Doran, Jared A. Hicks, Christopher P. Mckay, John Charles Priscu
Modeling The Thickness Of Perennial Ice Covers On Stratified Lakes Of The Taylor Valley, Antarctica, Maciej K. Obryk, Peter T. Doran, Jared A. Hicks, Christopher P. Mckay, John Charles Priscu
Geology Faculty Publications and Presentations
A 1-D ice cover model was developed to predict and constrain drivers of long-term ice thick-ness trends in chemically stratified lakes of Taylor Valley, Antarctica. The model is driven by surface ra-diative heat fluxes and heat fluxes from the underlying water column. The model successfully reproduced 16 a (between 1996 and 2012) of ice thickness changes for the west lobe of Lake Bonney (average ice thickness = 3.53 m) and Lake Fryxell (average ice thickness = 4.22 m). Long-term ice thick-ness trends require coupling with the thermal structure of the water column. The heat stored within the temperature maximum of …
Förster Resonance Energy Transfer Between Molecules In The Vicinity Of Graphene- Coated Nanoparticles, Tingting Bian, Railing Chang, Pui T. Leung
Förster Resonance Energy Transfer Between Molecules In The Vicinity Of Graphene- Coated Nanoparticles, Tingting Bian, Railing Chang, Pui T. Leung
Physics Faculty Publications and Presentations
The recent demonstration of the plasmonic enhanced Förster resonance energy transfer (FRET) between two molecules in the vicinity of planar graphene monolayers is further investigated using graphene-coated nanoparticles (GNP). Due to the flexibility of these nanostructures in terms of their geometric (size) and dielectric (e.g. core material) properties, greater tunability of the FRET enhancement can be achieved employing the localized surface plasmons. It is found that while the typical characteristic graphene plasmonic enhancements are manifested from using these GNP’s, even higher enhancements can be possible via doping and manipulating the core materials. In addition, the broadband characteristics is further expanded …
The Physics Of Juggling A Spinning Ping-Pong Ball., Ralf Widenhorn
The Physics Of Juggling A Spinning Ping-Pong Ball., Ralf Widenhorn
Physics Faculty Publications and Presentations
Juggling a spinning ball with a ping-pong paddle represents a challenge both in terms of hand-eye coordination and physics concepts. Here, we analyze the ping-pong ball’s motion, and explore how the correct paddle angle relates to the ball’s spin and speed, as it moves vertically up and down. For students, this requires engaging with concepts like momentum, angular momentum, free-body diagrams, and friction. The activities described in this article include high-speed video motion tracking of the ping-pong ball and the investigation of the frictional characteristics of the paddle. They can be done in a physics lab or at home, requiring …
Fast And Adaptive Indexing Of Multi-Dimensional Observational Data, Sheng Wang, David Maier, Beng Chin Ooi
Fast And Adaptive Indexing Of Multi-Dimensional Observational Data, Sheng Wang, David Maier, Beng Chin Ooi
Computer Science Faculty Publications and Presentations
Sensing devices generate tremendous amounts of data each day, which include large quantities of multi-dimensional measurements. These data are expected to be immediately available for real-time analytics as they are streamed into storage. Such scenarios pose challenges to state-of-the-art indexing methods, as they must not only support efficient queries but also frequent updates. We propose here a novel indexing method that ingests multi-dimensional observational data in real time. This method primarily guarantees extremely high throughput for data ingestion, while it can be continuously refined in the background to improve query efficiency. Instead of representing collections of points using Minimal Bounding …
Inverse Structure Functions In The Canonical Wind Turbine Array Boundary Layer, Bianca Viggiano, Moira Gion, Naseem Ali, Murat Tutkun, Raúl Bayoán Cal
Inverse Structure Functions In The Canonical Wind Turbine Array Boundary Layer, Bianca Viggiano, Moira Gion, Naseem Ali, Murat Tutkun, Raúl Bayoán Cal
Mechanical and Materials Engineering Faculty Publications and Presentations
Wind tunnel measurements for a 3×3 canonical wind turbine array boundary layer are obtained using hot-wire anemometer velocity signals. Two downstream locations are considered, referring to the near- and far-wake, and 21 vertical points are acquired per profile. Velocity increments and exit distances are used to quantify inverse structure functions at both downstream locations. Inverse structure functions in the near-wake show a similar profile for the main vertical locations, but diverge as the moment is increased. In the far-wake, inverse structure functions converge toward a single function for all vertical location and moments. The scaling exponents for inverse structure functions …
Discontinuities In Hygroscopic Growth Below And Above Water Saturation For Laboratory Surrogates Of Oligomers In Organic Atmospheric Aerosols, Natasha Hodas, Andreas Zuend, Katherine Schilling, Thomas Berkemeier, Manabu Shiraiwa, Richard C. Flagan, John H. Seinfeld
Discontinuities In Hygroscopic Growth Below And Above Water Saturation For Laboratory Surrogates Of Oligomers In Organic Atmospheric Aerosols, Natasha Hodas, Andreas Zuend, Katherine Schilling, Thomas Berkemeier, Manabu Shiraiwa, Richard C. Flagan, John H. Seinfeld
Environmental Science and Management Faculty Publications and Presentations
Discontinuities in apparent hygroscopicity below and above water saturation have been observed for organic and mixed organic–inorganic aerosol particles in both laboratory studies and in the ambient atmosphere. However, uncertainty remains regarding the factors that contribute to observations of low hygroscopic growth below water saturation but enhanced cloud condensation nuclei (CCN) activity for a given aerosol population. Utilizing laboratory surrogates for oligomers in atmospheric aerosols, we explore the extent to which such discontinuities are influenced by organic component molecular mass and viscosity, non-ideal thermodynamic interactions between aerosol components, and the combination of these factors. Measurements of hygroscopic growth under subsaturated …
Ecological Investigations To Select Mitigation Options To Reduce Vehicle-Caused Mortality Of A Threatened Butterfly, Sara B. Zielin, Jalene Littlejohn, Catherine E. De Rivera, Winston P. Smith, Sandra L. Jacobson
Ecological Investigations To Select Mitigation Options To Reduce Vehicle-Caused Mortality Of A Threatened Butterfly, Sara B. Zielin, Jalene Littlejohn, Catherine E. De Rivera, Winston P. Smith, Sandra L. Jacobson
Environmental Science and Management Faculty Publications and Presentations
Whereas roads that bisect habitat are known to decrease population size through animal-vehicle collisions or interruption of key life history events, it is not always obvious how to reduce such impacts, especially for flying organisms. We needed a quick, cost-efficient and effective way to determine how best to decrease vehicle-caused mortality while maintaining habitat connectivity for the federally listed Oregon silverspot butterfly, Speyeria zerene hippolyta. Therefore, we gathered targeted ecological information that informed selection of a mitigation option prior to implementation. We sampled butterfly behavior and environmental conditions along a highway and conducted a small-scale experiment along a decommissioned …
Variation In Green Roof Storage Capacity, Associated Drivers, And Implications For Stormwater Management In Portland, Oregon, Melecio Estrella
Variation In Green Roof Storage Capacity, Associated Drivers, And Implications For Stormwater Management In Portland, Oregon, Melecio Estrella
University Honors Theses
Greens roofs, also known as ecoroofs or living roofs, provide numerous ecosystem services and are becoming widely integrated into urban stormwater management systems. Despite a long and robust history of green roof projects in Portland, Oregon, there is a distinct lack of research on in situ performance. This thesis addressed this gap by investigating the hydrologic performance of five green roofs in Portland for a time period spanning November through February. Despite difficulty with the sensor calibrations, our analysis of moisture content data from these roofs revealed variation in: (1) total evapotranspiration, which serves as a proxy for total stormwater …
Mapped Tent Pitching Schemes For Hyperbolic Systems, Jay Gopalakrishnan, Joachim Schöberl, C. Wintersteiger
Mapped Tent Pitching Schemes For Hyperbolic Systems, Jay Gopalakrishnan, Joachim Schöberl, C. Wintersteiger
Portland Institute for Computational Science Publications
A spacetime domain can be progressively meshed by tent shaped objects. Numerical methods for solving hyperbolic systems using such tent meshes to advance in time have been proposed previously. Such schemes have the ability to advance in time by different amounts at different spatial locations. This paper explores a technique by which standard discretizations, including explicit time stepping, can be used within tent-shaped spacetime domains. The technique transforms the equations within a spacetime tent to a domain where space and time are separable. After detailing techniques based on this mapping, several examples including the acoustic wave equation and the Euler …