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Portland State University

2006

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Comparison Of The Variation Between Asce Penman-Monteith Reference Evapotranspiration And Potential Evaporation In Oregon, Chad M. Cary Jan 2006

Comparison Of The Variation Between Asce Penman-Monteith Reference Evapotranspiration And Potential Evaporation In Oregon, Chad M. Cary

Dissertations and Theses

Evapotranspiration (ET) is an important input in terrestrial water balance equations used in modeling streamflow. Good ET estimates are critical to producing reasonable seasonal and annual streamflow predictions. Due to the lack of sufficient instruments to directly measure ET, researchers have developed numerous empirical equations that use climatic variables to estimate this element. Based on studies over the last 50 years, the American Society of Civil Engineers (ASCE) has standardized the calculation of evapotranspiration with the Penman-Monteith equation. Using the ASCE Penman-Monteith equation, this study compares reference ET (ET0) estimates to potential evaporation (PE) generated from a study …

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Asymmetry Of Tidal Plume Fronts In An Eastern Boundary Current Regime, David A. Jay, Jiayi Pan, Philip M. Orton, Alexander R. Horner-Devine Jan 2006

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 …

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Hydrodynamics And Morphology In The Ems/Dollard Estuary: Review Of Models, Measurements, Scientific Literature, And The Effects Of Changing Conditions, Stefan A. Talke, Huib E. De Swart Jan 2006

Hydrodynamics And Morphology In The Ems/Dollard Estuary: Review Of Models, Measurements, Scientific Literature, And The Effects Of Changing Conditions, Stefan A. Talke, Huib E. De Swart

Civil and Environmental Engineering Faculty Publications and Presentations

The Ems estuary has constantly changed over the past centuries both from man-made and natural influences. On the time scale of thousands of years, sea level rise has created the estuary and dynamically changed its boundaries. More recently, storm surges created the Dollard sub-basin in the 14th -15th centuries. Beginning in the 16th century, diking and reclamation of land has greatly altered the surface area of the Ems estuary, particularly in the Dollard. These natural and anthropogenic changes to the surface area of the Ems altered the flow patterns of water, the tidal characteristics, and the patterns of sediment deposition …

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Ce-Qual-W2: A Two-Dimensional, Laterally Averaged, Hydrodynamic And Water Quality Model, Version 3.5, Thomas M. Cole, Scott A. Wells Jan 2006

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 …

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The Aeolian Flux Of Calcium, Chloride And Nitrate To The Mcmurdo Dry Valleys Landscape: Evidence From Snow Pit Analysis, Rebecca A. Witherow, W. Berry Lyons, Nancy A. Bertler, Kathleen A. Welch, Paul A. Mayewski, Sharon B. Sneed, Thomas H. Nylen, Michael J. Handley, Andrew G. Fountain Jan 2006

The Aeolian Flux Of Calcium, Chloride And Nitrate To The Mcmurdo Dry Valleys Landscape: Evidence From Snow Pit Analysis, Rebecca A. Witherow, W. Berry Lyons, Nancy A. Bertler, Kathleen A. Welch, Paul A. Mayewski, Sharon B. Sneed, Thomas H. Nylen, Michael J. Handley, Andrew G. Fountain

Geography Faculty Publications and Presentations

We have determined the flux of calcium, chloride and nitrate to the McMurdo Dry Valleys region by analysing snow pits for their chemical composition and their snow accumulation using multiple records spanning up to 48 years. The fluxes demonstrate patterns related to elevation and proximity to the ocean. In general, there is a strong relationship between the nitrate flux and snow accumulation, indicating that precipitation rates may have a great influence over the nitrogen concentrations in the soils of the valleys. Aeolian dust transport plays an important role in the deposition of some elements (e.g. Caý?) into the McMurdo Dry …

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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 Jan 2006

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.

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Kernels Of Directed Graph Laplacians, John S. Caughman Iv, J. J. P. Veerman Jan 2006

Kernels Of Directed Graph Laplacians, John S. Caughman Iv, J. J. P. Veerman

Mathematics and Statistics Faculty Publications and Presentations

Let G denote a directed graph with adjacency matrix Q and in- degree matrix D. We consider the Kirchhoff matrix L = D − Q, sometimes referred to as the directed Laplacian. A classical result of Kirchhoff asserts that when G is undirected, the multiplicity of the eigenvalue 0 equals the number of connected components of G. This fact has a meaningful generalization to directed graphs, as was observed by Chebotarev and Agaev in 2005. Since this result has many important applications in the sciences, we offer an independent and self-contained proof of their theorem, showing in this paper …

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The Convergence Of V-Cycle Multigrid Algorithms For Axisymmetric Laplace And Maxwell Equations, Jay Gopalakrishnan, Joseph E. Pasciak Jan 2006

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 …

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Families Challenged By Children's Mental Health: Employment And Community Integration, Eileen M. Brennan, Katherine J. Huffstutter, Julie M. Rosenzweig, Jennifer R. Bradley Jan 2006

Families Challenged By Children's Mental Health: Employment And Community Integration, Eileen M. Brennan, Katherine J. Huffstutter, Julie M. Rosenzweig, Jennifer R. Bradley

School of Social Work Faculty Publications and Presentations

Slides of a presentation given to the conference 'Work, Stress, and Health 2006: Making a Difference in the Workplace' held in Miami, FL, in 2006.

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Place, Sport And Globalization: Making Sense Of La Marca Barça, Hunter Shobe Jan 2006

Place, Sport And Globalization: Making Sense Of La Marca Barça, Hunter Shobe

Geography Faculty Publications and Presentations

The case of Football Club (FC) Barcelona provides a compelling case for
examining the impact of globalization on the place/identity role of football
clubs. FC Barcelona has deep historical connections to Barcelona and
Catalonia. These connections were de-emphasized by the clubs leadership
under Josep Lluís Núñez (1978-2000) and Joan Gaspart (2000-2003) and
promoted again by Joan Laporta and his directors (elected in 2003). At the
same time, under Laporta, FC Barcelona has developed into a successful
global brand. How are we to understand this renewed focus on the local and
national discourses of place while the team is simultaneously promoted …

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The Light On The Horizon: Imagining The Death Of American Cities, Carl Abbott Jan 2006

The Light On The Horizon: Imagining The Death Of American Cities, Carl Abbott

Urban Studies and Planning Faculty Publications and Presentations

Cities in the United States have never known the direct effects of total war. Lacking this bitter experience, Americans have had to imagine the impacts of catastrophic warfare on their urban centers. This paper examines fictional depictions of future warfare as it has been imagined to affect U.S. cities, particularly since 1945. It draws on films, short stories, and novels from the "thriller," "future war," and science fiction genres to explore common assumptions and underlying attitudes about cities and city life. It finds that cities are conspicuous by their absence from such stories of future war and its impacts. Cities …

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Urban History For Planners, Carl Abbott Jan 2006

Urban History For Planners, Carl Abbott

Urban Studies and Planning Faculty Publications and Presentations

This article analyzes the conceptual and historiographic differences between the closely related fields of urban history and planning history. It reviews the origins of urban history as a distinct field and argues that work in urban history falls into three broad categories dealing with civic life, individual and group relations, and the physical evolution of urban places. It identifies topics that are particularly fruitful and generate new scholarship, and suggests ways in which each of these realms of urban history raises questions of relevance to urban planning and urban policy.

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Science And Intractable Conflict, Connie P. Ozawa Jan 2006

Science And Intractable Conflict, Connie P. Ozawa

Urban Studies and Planning Faculty Publications and Presentations

Using illustrative examples, this article describes how science and other types of information often are used in an attempt to settle Conflict. Expectations for science to arbitrate differences may be misplaced, however, and such misuse of science can aggravate and exacerbate Conflict. Instead, effective resolution may be facilitated by focusing on facts that matter, acknowledging the value of varied sorts and sources of information, and recognizing scientific uncertainty.

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Evaluating A New Urbanist Neighborhood, Jennifer Dill Jan 2006

Evaluating A New Urbanist Neighborhood, Jennifer Dill

Urban Studies and Planning Faculty Publications and Presentations

New Urbanist neighborhoods aim to improve sustainability by reducing automobile use, increasing walking and cycling, increasing the diversity of land uses and people, and increasing social capital, through strengthened personal and civic bonds. With more New Urbanist communities being constructed, it is now more feasible and necessary to evaluate their success. Much of the existing research uses older, traditional neighborhoods as a proxy for New Urbanism. This research compares a New Urbanist development with two conventional subdivisions and finds that some of the objectives are being fulfi lled, in both direct and indirect ways. While New Urbanist residents are walking …

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Image-Based Nanocrystallography With Online Database Support, Peter Moeck, Ján Zahornadsky, Boris Dusek Jan 2006

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.

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Lattice Fringe Fingerprinting In Two Dimensions With Database Support, Peter Moeck, B. Seipel, R. Bjorge, P. Fraundorf Jan 2006

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.

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Engineering Education Through Service-Learning In Developing Communities: Two Case Studies, Evan A. Thomas, Andrew Azman Jan 2006

Engineering Education Through Service-Learning In Developing Communities: Two Case Studies, Evan A. Thomas, Andrew Azman

Mechanical and Materials Engineering Faculty Publications and Presentations

This paper provides case studies of two service learning projects that University of Colorado at Boulder (CU-Boulder) students are integrating into their academic experience. The projects focus on developing communities and are managed under the auspices of Engineers Without Borders-USA (EWB-USA), a group founded by Dr. Bernard Amadei, Professor of Civil Engineering at CU-Boulder. These projects expand students? understanding of the social value of their chosen profession, and expose them to a type of engineering significantly different than what is presented in most of their classes. Specifically, focusing on developing communities provides students with the opportunity to design solutions to …

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