Digital Commons Network^™

Asymmetry Of Tidal Plume Fronts In An Eastern Boundary Current Regime, David A. Jay, Jiayi Pan, Philip M. Orton, Alexander R. Horner-Devine

Civil and Environmental Engineering Faculty Publications and Presentations

The Columbia River tidal plume or near-field is formed twice daily by the ebb outflow of the Columbia River. It is a part of a larger, anticyclonic plume bulge, which in turn is embedded in far-field plume and coastal waters. Because of the mixing caused directly and indirectly by plume fronts, the interaction of the tidal plume and bulge with the California Current upwelling regime plays a vital role in coastal productivity on the Oregon and Washington shelves. The tidal plume is initially supercritical with respect to the internal Froude number on all stronger ebbs. It is separated from the …

The Convergence Of V-Cycle Multigrid Algorithms For Axisymmetric Laplace And Maxwell Equations, Jay Gopalakrishnan, Joseph E. Pasciak

Mathematics and Statistics Faculty Publications and Presentations

We investigate some simple finite element discretizations for the axisymmetric Laplace equation and the azimuthal component of the axisymmetric Maxwell equations as well as multigrid algorithms for these discretizations. Our analysis is targeted at simple model problems and our main result is that the standard V-cycle with point smoothing converges at a rate independent of the number of unknowns. This is contrary to suggestions in the existing literature that line relaxations and semicoarsening are needed in multigrid algorithms to overcome difficulties caused by the singularities in the axisymmetric Maxwell problems. Our multigrid analysis proceeds by applying the well known regularity …

Oxygen Demand Trends, Land Cover Change, And Water Quality Management For An Urbanizing Oregon Watershed, Michael Karl Boeder

Dissertations and Theses

In-stream aquatic habitat depends on adequate levels of dissolved oxygen. Human alteration of the landscape has an extensive influence on the biogeochemical processes that drive oxygen cycling in streams. Historic datasets allow researchers to track trends in chemical parameters concomitant with urbanization, while land cover change analysis allows researchers to identify linkages between water quality trends and landscape change.

Using the Seasonal Kendall's test, I examined water quality trends in oxygen demand variables during the mid-1990s to 2003, for twelve sites in the Rock Creek sub-watershed of the Tualatin River, northwest Oregon. Significant trends occurred in each parameter. Dissolved oxygen …

Fundamentals For Student Success In The Middle Grades, Mike Muir, Vincent A. Anfara Jr., P. Gayle Andrews, Micki M. Caskey, Steven B. Mertens, David Hough

Curriculum and Instruction Faculty Publications and Presentations

Determining how to provide the best education possible for young adolescents begins with the answers to three essential questions: Who are young adolescents? What do we know about them, their abilities, interests and strengths? Based on what we know about young adolescents, what should schools do to provide a quality education for each and every student? And finally, is there evidence that these recommended practices improve student achievement? How do we know programs and practices designed specifically with young adolescents in mind make a difference? To answer these questions, we will first outline some of the developmental characteristics of young …

Image-Based Nanocrystallography With Online Database Support, Peter Moeck, Ján Zahornadsky, Boris Dusek

Physics Faculty Publications and Presentations

The crystallographic phase and morphology of many materials change with the crystal size so that new needs arise to determine the crystallography of nanocrystals. Direct space high-resolution phase-contrast transmission electron microscopy (HRTEM) and atomic resolution scanning TEM (STEM) when combined with tools for image-based nanocrystallography in two (2D) and three (3D) dimensions possess the capacity to meet these needs. After a concise discussion of lattice-fringe visibility spheres and maps, this paper discusses lattice-fringe fingerprinting in 2D and tilt protocol applications. On-line database developments at Portland State University (PSU) that support image-based nanocrystallography are also mentioned.

Lattice Fringe Fingerprinting In Two Dimensions With Database Support, Peter Moeck, B. Seipel, R. Bjorge, P. Fraundorf

Physics Faculty Publications and Presentations

A brief introduction to lattice fringe fingerprinting in two dimensions (2D) with database support is given. The method is employed for the identification of the crystal phase of a small ensemble of nanocrystals. The enhanced viability of this method in aberration-corrected transmission electron microscopes (TEMs) and scanning TEMs (STEMs) is also illustrated.

Periodic Atlas Of The Metroscape: The Geography Of Water, Vivek Shandas, Alton Straub, Yongxia Kou

Institute for Sustainable Solutions Publications and Presentations

Describes the geography of water in the Portland, Oregon metropolitan area: groundwater, rivers, irrigation, water supply, and sewer lines.

Interview With Myo Demayo, Urbanstead Farm (Audio), Myo Demayo

All Sustainability History Project Oral Histories

Interview of Myo DeMayo by Tyler Anderson.

The interview index is available for download.

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Binary Decision Diagrams And Crisp Possibilistic Reconstructability Analysis, Martin Zwick, Alan Mishchenko

Complex Systems Faculty Publications and Presentations

The paper discusses the application of Binary Decision Diagrams (BDDs) in the reconstructability analysis of crisp possibilistic systems. In particular, we show how BDDs can be used to represent set-theoretic relations and implement the three basic operations of reconstructability analysis.

Combining Linear Regression With Reconstructability Analysis: A Study Of Differences In Health Status, Renato Carletti, Martin Zwick

Complex Systems Faculty Publications and Presentations

A linear regression model was used to predict variations in health status with the hypothesis that literacy level as a proximal measure for educational attainment would show a strong correlation with health status. Groups of other independent variables have also been introduced in the model to test whether the effect of literacy on health would have been mediated by other factors, or increased by them. The linear regression model did not show any strong relation between literacy and health, but pointed to other factors as predictors of health status.

Methods of data mining have been used for exploring throughout all …

The Heart Of The Matter: Aligning Curriculum, Pedagogy And Engagement In Higher Education, Kevin Kecskes, Seanna Kerrigan, Judy Patton

Public Administration Faculty Publications and Presentations

This essay explores the themes of curriculum and pedagogy, as outlined by the editors of this special edition, in the context of Portland State University's institutional transformation. We elucidate select mechanisms that support curricular-community interactions, known at PSU as "community-based learning." In doing so we discuss how CBL and other civic engagement strategies relate to the disciplines, departments, and interdisciplinary work as well as how these various collaborative approaches affect pedagogy and epistemology at PSU.

Variation In The Response Of Crustacean Zooplankton Species Richness And Composition To The Invasive Predator Bythotrephes Longimanus, Angela L. Strecker, Shelley E. Arnott, Norman D. Yan, Robert Girard

Environmental Science and Management Faculty Publications and Presentations

The predacious invertebrate Bythotrephes longimanus has invaded >90 freshwater lakes in North America. There is some evidence that B. longimanus has a negative effect on summer zooplankton species richness; however, no study has examined the effect of B. longimanus throughout the ice-free season in more than one lake. We visited 10 invaded and 4 reference lakes every 2 weeks from May to September, collecting B. longimanus, crustacean zooplankton, and water chemistry samples. Composite samples were pooled across the study season for each lake. Bythotrephes longimanus significantly reduced cladoceran species richness, diversity, and abundance, and the total zooplankton community also exhibited …

Changes In Riparian Vegetation Buffers In Response To Development In Three Oregon Cities, J. Alan Yeakley, Connie P. Ozawa, A. M. Hook

Environmental Science and Management Faculty Publications and Presentations

Riparian vegetation buffer loss was investigated for three cities with contrasting local regulatory controls in urbanizing northwest Oregon. The cities examined were Hillsboro, Oregon City and Portland, all having experienced high rates of population increase in the 1990s. All cities are covered under Oregon’s land use law that provides goals for the protection of open space and natural resources. On the municipality level, regulatory controls in Portland included a system of environmental zoning for riparian area protection, while regulatory controls on development in riparian areas in Hillsboro and Oregon City were less stringent. Digital aerial photographs covering buffer areas within …

Addressing Cheating And Workload Characterization In Online Games, Christopher Chambers

Dissertations and Theses

The Internet has enabled the popular pastime of playing video games to grow rapidly by connecting game players in disparate locations. However, with popularity have come the two challenges of hosting a large number of users and detecting cheating among users. For reasons of control, security, and ease of development, the most popular system for hosting on-line games is the client server architecture. This is also the most expensive and least scalable architecture for the game publisher, which drives hosting costs upwards with the success of the game. In addition to the expense of hosting, as a particular game grows …

Ce-Qual-W2: A Two-Dimensional, Laterally Averaged, Hydrodynamic And Water Quality Model, Version 3.5, Thomas M. Cole, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

This manual documents the two-dimensional, laterally averaged, hydrodynamic and water quality model CE-QUAL-W2. This manual was prepared in the Environmental Laboratory (EL), us Army Engineer Waterways Experiment Station (WES), Vicksburg, MS. Bonita Niel and Dr. William Roper, CERD-C provided funding for Version 3.1 of the manual under the Numerical Model Maintenance Program. The principal investigator for Version 3.2 of CE-QUAL-W2 and the User Manual was Mr. Thomas M. Cole of the Water Quality and Contaminant Modeling Branch (WQCMB), Environmental Processes and Effects Division (EPED), EL. This report supersedes the Version 3.2 manual. Revisions made in this V3.5 manual were made …

2005 Diamond Lake Submersed Aquatic Vegetation Survey, Mark D. Sytsma, Mary Pfauth

Center for Lakes and Reservoirs Publications and Presentations

Diamond Lake is a large natural lake having a surface area of some 3214 acres (1300.7 hectares) and a maximum depth of 52 feet (15.8 meters). It is located within the Umpqua National Forest in the Southern Cascade Mountains of Oregon, at an elevation of over 5000 feet (>1524 meters). Diamond Lake is a high-use waterbody that supports angling, public campgrounds, recreational boating, swimming, and water skiing. The human activity associated with the lake has been a significant contributor to the economy of southern Oregon since the early part of the twentieth century.

Historically Diamond Lake was fishless but …

Comments On The Mechanism Of Aging Of Antimony Doped Tin Oxide Based Electrochromic Devices, Joo C. Chan, Nicole A. Hannah, Shankar B. Rananavare, Laura Yeager, Liviu Dinescu, Ashok Saraswat, Pradeep Iyer, James P. Coleman

Chemistry Faculty Publications and Presentations

Electrochromic effects of antimony doped tin oxide (ATO) nanoparticles are investigated to probe device yellowing (degradation). Voltage vs contrast ratio curves exhibit hysteresis, i.e., image-sticking phenomena due to irreversible charge insertion. X-ray, impedance and optical b* studies suggest that the yellowing/charge trapping is nanoparticle size-dependent with 4 nm size particles exhibiting the least yellowing. Yellowing results in increased impedances of electrode–electrolyte interface and electrode corrosion. Plausible sources of discoloration are formation of insulating complex alkali oxide film, carrier inversion (n-to-p type) through electrochemical Li doping, redeposition of the corroded electrode material and perhaps residual concentration of charge-transfer species.

Investigation Of The Probe-Sample Interaction In The Ultrasonic/Shear-Force Microscope: The Phononic Friction Mechanism, Xiquan Cui, Andres H. La Rosa

Physics Faculty Publications and Presentations

The dissipative and conservative interactions between a sharp probe and a flat Si sample in the ultrasonic/shear-force microscope are investigated. It is shown that, when working in the ambient condition, there are two distinct probe-sample interaction regions: the pure dissipative interaction region in the relatively far probe-sample distance, and the highly correlated dissipative and conservative interaction region in the close probe-sample distance. The ultrasonic data suggest that the phonon generation is a dissipative channel for the probe-sample interaction in the shear force microscope. A shaking potential model is proposed to explain the phononic friction mechanism

Diversity Of Methanogens And Other Archaea In Permanently Cold, Anoxic Marine Sediments, Melissa Mary Kendell

Dissertations and Theses

Little is known about the mechanism of methanogenic degradation of acetate or the fate of hydrogen and formate in cold marine sediments, or the ability of methanogens to grow and produce methane there. We used cultivation and molecular techniques to examine the microbes that produce methane from these substrates in permanently cold, anoxic marine sediments at Skan Bay, Alaska (57°N, 167°W, depth 65 m), at the Nankai Trough (32°21'N, 134°56'E, depth 247 m), and at Hydrate Ridge, Oregon (44°35'N, 125°10'W, depth 800 m). Most probable number (MPN) analyses were conducted for CO2-reducing, methylotrophic, and aceticlastic methanogens from Skan Bay and …

Structural And Chiroptical Properties Of The Two Coordination Isomers Of Ybdota-Type Complexes, Lorenzo Di Bari, Gennaro Pescitelli, A. Dean Sherry, Mark Woods

Chemistry Faculty Publications and Presentations

Studies of the structural, physical, and chemical properties of the lanthanide(III) complexes of DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) and related ligands are often complicated by the presence of two coordination isomers in solution. Since these coordination isomers are in exchange and cannot be separated, many techniques offer information only on the weighted average of the two isomers. Lanthanide ion complexes formed with the ligands S(RRRR)NO₂BnDOTMA and S(SSSS)NO₂BnDOTMA preferentially adopt only one of the two common coordination isomers in solution, so the ytterbium complexes of these ligands offer a unique opportunity to study …

Effects Of Gramicidin-A On The Adsorption Of Phospholipids To The Air–Water Interface, Samares C. Biswas, Shankar B. Rananavare, Stephen B. Hall

Chemistry Faculty Publications and Presentations

Prior studies suggest that the hydrophobic surfactant proteins, SP-B and SP-C, promote adsorption of the lipids in pulmonary surfactant to an air–water interface by stabilizing a negatively curved rate-limiting structure that is intermediate between bilayer vesicles and the surface film. This model predicts that other peptides capable of stabilizing negative curvature should also promote lipid adsorption. Previous reports have shown that under appropriate conditions, gramicidin-A (GrA) induces dioleoyl phosphatidylcholine (DOPC), but not dimyristoyl phosphatidylcholine (DMPC), to form the negatively curved hexagonal-II (HII) phase. The studies reported here determined if GrA would produce the same effects on adsorption of DMPC and …

Sluice Boxes On The Shores: An Environmental History Of Gold Mining On Oregon's South Coast, Tania Louise Hyatt-Evenson

Dissertations and Theses

Environmental historians have researched, analyzed, and concluded that gold mining significantly altered the environment in Southern Oregon. Environmental case studies have examined mining's impact on the watersheds in the Rogue Valley, but none have analyzed the effect gold miners had on the Southern Oregon coast. While gold mining occurred on the South Coast from the 1850s to the 1940s, on a smaller scale, the impact from environmental change is just as significant. The purpose of this study is to understand how mining changed the landscape of the South Coast, and how this change affected the human populations that lived in …

Reconstructability Analysis As A Tool For Identifying Gene-Gene Interactions In Studies Of Human Diseases: Ieee Version, Martin Zwick, Stephen Shervais, Patricia Kramer

Complex Systems Faculty Publications and Presentations

There are a number of human diseases that are caused by the epistatic interaction of multiple genes. Detecting these interactions with standard statistical tools is difficult, because there may be an interaction effect, but minimal or no main effect. Reconstructability analysis uses Shannon’s information theory to detect relationships between variables in categorical datasets. We apply reconstructability analysis to data generated by five different models of gene-gene interaction, with heritability levels from 0.053 to 0.008, using 200 controls and 200 cases. We find that even with heritability levels as low as 0.008, and with the inclusion of 50 non-associated genes in …

Impact Of Bythotrephes Invasion On Zooplankton Communities In Acid-Damaged And Recovered Lakes On The Boreal Shield, Angela L. Strecker, Shelley E. Arnott

Environmental Science and Management Faculty Publications and Presentations

Invasive species introductions into freshwater ecosystems have had a multitude of effects on aquatic communities. Few studies, however, have directly compared the impact of an invader on communities with contrasting structure. Historically high levels and subsequent reductions of acid deposition have produced landscapes of lakes of varying acidity and zooplankton communitystructure. We conducted a 30-day enclosure experiment in Killarney Provincial Park, Ontario, Canada, to test the effects ofBythotrephes longimanus, an invasive invertebrate predator, on two contrasting zooplankton communities at different stages of recovery from acidification: recovered and acid damaged. Bythotrephes significantly decreased zooplankton biomass and abundance in both communities but …

Wavelet Based Feature Extraction And Dimension Reduction For The Classification Of Human Cardiac Electrogram Depolarization Waveforms, Christopher S. De Voir

Dissertations and Theses

An essential task for a pacemaker or implantable defibrillator is the accurate identification of rhythm categories so that the correct electrotherapy can be administered. Because some rhythms cause a rapid dangerous drop in cardiac output, it is necessary to categorize depolarization waveforms on a beat-to-beat basis to accomplish rhythm classification as rapidly as possible. In this thesis, a depolarization waveform classifier based on the Lifting Line Wavelet Transform is described. It overcomes problems in existing rate-based event classifiers; namely, (1) they are insensitive to the conduction path of the heart rhythm and (2) they are not robust to pseudo-events. The …

Frame-Shifting In Humor And Irony, L. David Ritchie

Communication Faculty Publications and Presentations

Coulson's (2001) analysis of humor as "frame-shifting" is extended to irony and compared to other current theories of humor and irony, including Giora's (2003) graded salience model. It is argued that the effects of humor and irony often depend on a subversive relationship between the initial and alternative frames, which adds to both cognitive and social meaning; understanding these effects requires consideration of the expansion of common ground (Clark, 1996) and relevance effects (Sperber & Wilson, 1986) triggered by the shift from a culturally licensed to a subversive frame. Reanalysis of several examples from recent studies in the light of …

Dependence, Dispersiveness, And Multivariate Hazard Rate Ordering, Baha-Eldin Khaledi, Subhash C. Kochar

Mathematics and Statistics Faculty Publications and Presentations

To compare two multivariate random vectors of the same dimension, we define a new stochastic order called upper orthant dispersive ordering and study its properties. We study its relationship with positive dependence and multivariate hazard rate ordering as defined by Hu, Khaledi, and Shaked (Journal of Multivariate Analysis, 2002). It is shown that if two random vectors have a common copula and if their marginal distributions are ordered according to dispersive ordering in the same direction, then the two random vectors are ordered according to this new upper orthant dispersive ordering. Also, it is shown that the marginal distributions of …

High-Resolution Angular Measurement Using Surface-Plasmon-Resonance Via Phase Interrogation At Optimal Incident Wavelengths, Hai-Pang Chiang, Jing-Lun Lin, Railing Chang, Sheng-Yu Su, P.T. Leung

Physics Faculty Publications and Presentations

It is demonstrated that ultrahigh-resolution angular measurement can be achieved via surface-plasmon-resonance excitation in which the phase difference between p- and s-polarized reflected waves is monitored as a function of the incidence angle. Resolutions down to 1.9 x 10(-6) deg are obtained by performing the measurements at optimal incident wavelengths. This represents an order of magnitude improvement compared with previously reported values.

Application Of Information-Theoretic Data Mining Techniques In A National Ambulatory Practice Outcomes Research Network, Adam Wright, Thomas N. Ricciardi, Martin Zwick

Complex Systems Faculty Publications and Presentations

The Medical Quality Improvement Consortium data warehouse contains de-identified data on more than 3.6 million patients including their problem lists, test results, procedures and medication lists. This study uses reconstructability analysis, an information-theoretic data mining technique, on the MQIC data warehouse to empirically identify risk factors for various complications of diabetes including myocardial infarction and microalbuminuria. The risk factors identified match those risk factors identified in the literature, demonstrating the utility of the MQIC data warehouse for outcomes research, and RA as a technique for mining clinical data warehouses.

Final Report Regional Lake Management Planning For Tmdl Development, Mark Sytsma

Center for Lakes and Reservoirs Publications and Presentations

Since the mid-1900’s, invasive aquatic weeds have been a significant problem in many of the lakes of the Clatsop Plains on the northern Oregon Coast. Weeds interfere with beneficial uses, such as boating, fishing and swimming, and have dramatically altered the chemical and biological features of the lakes. In 1994, the Oregon Department of Environmental Quality (ODEQ) added three of the lakes, Cullaby, Smith and Sunset, to the 303 (d) list of water quality impaired waters, due to the presence of the invasive aquatic weeds. ODEQ contracted with the Center for Lakes and Reservoirs and the Geology Department at PSU …