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Probabilistic Tsunami Hazard Assessment At Seaside, Oregon, For Near- And Far-Field Seismic Sources, Frank González, Eric L. Geist, Bruce Jaffe, Utku Kânoğlu, Harold O. Mofjeld, Costas Synolakis, Vasily V. Titov, Diego Rodriguez Arcas, Douglas Bellomo, David Carlton, Thomas Horning, Jeff Johnson, Jean Newman, Thomas Parsons, Robert Peters, Curt D. Peterson, George Priest, Angie Venturato, Joseph Weber, Florence L. Wong, Ahmet Yalçıner Nov 2009

Probabilistic Tsunami Hazard Assessment At Seaside, Oregon, For Near- And Far-Field Seismic Sources, Frank González, Eric L. Geist, Bruce Jaffe, Utku Kânoğlu, Harold O. Mofjeld, Costas Synolakis, Vasily V. Titov, Diego Rodriguez Arcas, Douglas Bellomo, David Carlton, Thomas Horning, Jeff Johnson, Jean Newman, Thomas Parsons, Robert Peters, Curt D. Peterson, George Priest, Angie Venturato, Joseph Weber, Florence L. Wong, Ahmet Yalçıner

Geology Faculty Publications and Presentations

The first probabilistic tsunami flooding maps have been developed. The methodology, called probabilistic tsunami hazard assessment (PTHA), integrates tsunami inundation modeling with methods of probabilistic seismic hazard assessment (PSHA). Application of the methodology to Seaside, Oregon, has yielded estimates of the spatial distribution of 100- and 500-year maximum tsunami amplitudes, i.e., amplitudes with 1% and 0.2% annual probability of exceedance. The 100-year tsunami is generated most frequently by far-field sources in the Alaska-Aleutian Subduction Zone and is characterized by maximum amplitudes that do not exceed 4 m, with an inland extent of less than 500 m. In contrast, the 500-year …


Water As A Complex System: Understanding The Dynamics In A Changing Environment, Heejun Chang Oct 2009

Water As A Complex System: Understanding The Dynamics In A Changing Environment, Heejun Chang

Systems Science Friday Noon Seminar Series

The water resources system is constantly evolving over space and time at a range of scales. Human-induced climate change and land development are probably two major driving forces of water resource system changes. However, the impacts of such changes are region specific, which depend on watershed characteristics such as topography and geology. Numerical simulation models are useful tools for understanding the system dynamics by allowing the multiple interactions of system components. I will introduce case studies of the Pacific Northwest that examine how changing climate and population growth affect regional water resources at multiple spatial and temporal scales and explain …


Similarity Of Nutrient Uptake And Root Dimensions Of Engelmann Spruce And Subalpine Fir At Two Contrasting Sites In Colorado, Melissa S. Lucash, Ruth D. Yanai, Karis J. Mcfarlane, Sarah E. Kulpa, Dustin M. Wood Oct 2009

Similarity Of Nutrient Uptake And Root Dimensions Of Engelmann Spruce And Subalpine Fir At Two Contrasting Sites In Colorado, Melissa S. Lucash, Ruth D. Yanai, Karis J. Mcfarlane, Sarah E. Kulpa, Dustin M. Wood

Environmental Science and Management Faculty Publications and Presentations

Nutrient uptake capacity is an important parameter in modeling nutrient uptake by plants. Researchers commonly assume that uptake capacity measured for a species can be used across sites. We tested this assumption by measuring the nutrient uptake capacity of intact roots of Engelmann spruce (Picea engelmanni Parry) and subalpine fir (Abies lasiocarpa (Hook.) Nutt.) at Loch Vale Watershed and Fraser Experimental Forest in the Rocky Mountains of central Colorado. Roots still attached to the tree were exposed to one of three concentrations of nutrient solutions for time periods ranging from 1 to 96h, and solutions were analyzed for ammonium, …


Model Reduction For Simulation, Optimization And Control, Oleg Edward Roderick Oct 2009

Model Reduction For Simulation, Optimization And Control, Oleg Edward Roderick

Dissertations and Theses

Many tasks of simulation, optimization and control can be performed more efficiently if the intermediate complexity of the numerical model is reduced. In our work, we investigate model reduction, as applied to reaction-transport systems of atmospheric chemistry. We use a Proper Orthogonal Decomposition-based approach to extract information from a set of model observations, and to project the model equations onto a reduced order space chosen in such a way that the essential model behavior is preserved in the solution of the reduced version. We examine and improve many features of the method. In particular, we show how to measure sensitivities …


Beyond Biobricks: Synthesizing Synergistic Biochemical Systems From The Bottom-Up, Mark A. Bedau Oct 2009

Beyond Biobricks: Synthesizing Synergistic Biochemical Systems From The Bottom-Up, Mark A. Bedau

Systems Science Friday Noon Seminar Series

Engineers who attempt to discover and optimize the behavior of complex biochemical systems face a dauntingly difficult task. This is especially true if the systems are governed by multiple qualitative and quantitative variables that have non-linear response functions and that interact synergistically. The synthetic biology community has responded to this difficulty by promoting the use of "standard biological parts" called "BioBricks", which are supposed to make biology into traditional engineering and enable engineers to "program living organisms in the same way a computer scientists can program a computer". But the BioBricks research program faces daunting hurdles, because the nonlinearity and …


Portland State Library Newsletter; Fall 2009, Portland State University Library Oct 2009

Portland State Library Newsletter; Fall 2009, Portland State University Library

Library Newsletters

In this issue: We Are Here to Help; News from Public Access Services; Portland State WorldCat; Exhibit & Events; History of Middle East Studies in the West Exhibit and Donor Honor Roll


Understanding Delivery Routes In Urban Areas, Miguel Figliozzi Oct 2009

Understanding Delivery Routes In Urban Areas, Miguel Figliozzi

TREC Project Briefs

Supply chains and urban areas cannot thrive without the efficient movement of goods. A recent study indicates that commercial vehicles carrying goods or providing services account for, on average, almost 10 percent of the total vehicle miles traveled (VMT) in medium to large urban areas. A predominant share of these trips takes place within a multi-stop tour. In order to develop a well-organized system for moving freight through urban areas, it is crucial to understand and quantify how routes and distribution decisions affect commercial vehicle flows and VMTs.

In the past, transportation planning models have focused on passenger movements but …


Effects Of Tide Gate Replacement On Water Temperature In A Freshwater Slough In The Columbia River Estuary, Sara Ennis Oct 2009

Effects Of Tide Gate Replacement On Water Temperature In A Freshwater Slough In The Columbia River Estuary, Sara Ennis

Environmental Science and Management Professional Master's Project Reports

Dramatic declines in salmon populations in the Pacific Northwest have brought new attention to the importance of estuarine rearing habitats. Levees and tide gates used to convert estuarine wetlands into farmland have reduced available habitat by more than half of historical levels. Recent efforts to restore estuarine habitats include tide gate replacement, though this method has been poorly studied. As a key indicator of salmon habitat suitability, temperature was used to evaluate the effects of tide gate replacement in a tidally influenced freshwater slough in the Lower Columbia River estuary. Three tide gates in the largest slough on Tenasillahe Island …


Effects Of Gaussian Fields On The Stability Of Inhomogeneously Broadened Lasers, Pitak Chenkosol, Lee W. Casperson Oct 2009

Effects Of Gaussian Fields On The Stability Of Inhomogeneously Broadened Lasers, Pitak Chenkosol, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

Under some conditions, spontaneous coherent pulsations are known to occur in the output beams of inhomogeneously broadened laser oscillators. These lasers typically operate with a Gaussian transverse field distribution, while the corresponding theoretical models assume a uniform-plane-wave field. The effects of a Gaussian field on the stability criteria of single-mode inhomogeneously broadened ring laser oscillators are considered in this study. It is found that in comparison to a plane wave a Gaussian field variation still permits low-threshold spontaneous pulsations but reduces the parameter space over which these pulsations can be observed.


A New Look At Richardson Number Mixing Schemes For Equatorial Ocean Modeling, Edward D. Zaron, James N. Moum Oct 2009

A New Look At Richardson Number Mixing Schemes For Equatorial Ocean Modeling, Edward D. Zaron, James N. Moum

Civil and Environmental Engineering Faculty Publications and Presentations

A reexamination of turbulence dissipation measurements from the equatorial Pacific shows that the turbulence diffusivities are not a simple function of the gradient Richardson number. A widely used mixing scheme, the K-profile parameterization, overpredicts the turbulent vertical heat flux by roughly a factor of 4 in the stably stratified region between the surface mixed layer and the Equatorial Undercurrent (EUC). Additionally, the heat flux divergence is of the incorrect sign in the upper 80 m. An alternative class of parameterizations is examined that expresses the mixing coefficients in terms of the large-scale kinetic energy, shear, and Richardson number. These representations …


How Does A Visual Monitoring System Foster Sustainable Behavior?, Melissa Haeffner, Federico Casalegno Oct 2009

How Does A Visual Monitoring System Foster Sustainable Behavior?, Melissa Haeffner, Federico Casalegno

Environmental Science and Management Faculty Publications and Presentations

Americans spend upwards of 90% of each day in buildings that account for two-thirds of electricity usage. Because the supply of smart buildings will take time to catch up with demand, efforts are sought to develop informed and educated people to live and work in these “dumb” buildings. Additionally, energy efficiency alone may be inadequate to achieve major reduction in carbon emissions (Darby, 2006). Finding ways to intentionally change the lifestyle behavior in a household should have significant implications in reducing environmental impacts as fossil energy use in resident homes is directly related to the exploitation of natural resources and …


Practical Approximations To Quantify The Impact Of Time Windows And Delivery Sizes On Freight Vmt In Urban Areas, Miguel A. Figliozzi Oct 2009

Practical Approximations To Quantify The Impact Of Time Windows And Delivery Sizes On Freight Vmt In Urban Areas, Miguel A. Figliozzi

TREC Final Reports

This paper studies approximations to the average length of Vehicle Routing Problems (VRP). The approximations are valuable for strategic and planning analysis of transportation and logistics problems. The research focus is on VRP with varying number of customers, demands, and locations. This modeling environment can be used in transport and logistics models that deal with a distribution center serving an area with daily variations in the demand. The routes are calculated daily based on what freight is available. New approximations and experimental settings are introduced. Average distance travelled is estimated as a function of the number of customers served and …


Plasmonic Enhancement Of Forster Energy Transfer Between Two Molecules In The Vicinity Of A Metallic Nanoparticle: Nonlocal Optical Effects, P.T. Leung, H. Y. Xie, H. Y. Chung, D. P. Tsai Oct 2009

Plasmonic Enhancement Of Forster Energy Transfer Between Two Molecules In The Vicinity Of A Metallic Nanoparticle: Nonlocal Optical Effects, P.T. Leung, H. Y. Xie, H. Y. Chung, D. P. Tsai

Physics Faculty Publications and Presentations

The problem of Forster resonance energy transfer (FRET) between two molecules in the vicinity of a metallic nanoparticle such as a nanoshell is studied within a phenomenological model which takes into account the nonlocal optical response of the metal. This model allows for arbitrary locations and orientations of the two molecular dipoles with respect to the metal particle which can be of ultrasmall sizes (nm) and for which nonlocal effects are of high significance. In particular, for the nanoshell case, the molecules can be located both outside, both inside, or one inside and one outside the shell. Also, the case …


Lipid-Protein Interactions Probed By Electron Crystallography, Steve L. Reichow, Tamir Gonen Oct 2009

Lipid-Protein Interactions Probed By Electron Crystallography, Steve L. Reichow, Tamir Gonen

Chemistry Faculty Publications and Presentations

Electron crystallography is arguably the only electron cryomicroscopy (cryoEM) technique able to deliver an atomic-resolution structure of membrane proteins embedded in the lipid-bilayer. In the electron crystallographic structures of the light driven ion pump, bacteriorhodopsin, and the water channel, aquaporin-0, sufficiently high resolution was obtained and both lipid and protein were visualized, modeled and described in detail. An extensive network of lipid-protein interactions mimicking native membranes is established and maintained in two-dimensional (2D) crystalline vesicles used for structural analysis by electron crystallography. Lipids are tightly integrated into the protein's architecture where they can affect the function, structure, quaternary assembly and …


Tracking Rhythmicity In Biomedical Signals Using Sequential Monte Carlo Methods, Sungan Kim Sep 2009

Tracking Rhythmicity In Biomedical Signals Using Sequential Monte Carlo Methods, Sungan Kim

Dissertations and Theses

Cyclical patterns are common in signals that originate from natural systems such as the human body and man-made machinery. Often these cyclical patterns are not perfectly periodic. In that case, the signals are called pseudo-periodic or quasi-periodic and can be modeled as a sum of time-varying sinusoids, whose frequencies, phases, and amplitudes change slowly over time. Each time-varying sinusoid represents an individual rhythmical component, called a partial, that can be characterized by three parameters: frequency, phase, and amplitude. Quasi-periodic signals often contain multiple partials that are harmonically related. In that case, the frequencies of other partials become exact integer multiples …


Simulation Of Insb Devices Using Drift-Diffusion Equations, Edin Sijercic Sep 2009

Simulation Of Insb Devices Using Drift-Diffusion Equations, Edin Sijercic

Dissertations and Theses

Silicon technology has for several decades followed Moore's law. Reduction of feature dimensions has resulted in constant increase in device density which has enabled increased functionality. Simultaneously, performance, such as circuit speed, has been improving. Recently, this trend is in jeopardy due to, for example, unsustainable increase in the processor power dissipation. In order to continue development trends, as outlined in ITRS roadmap, new approaches seem to be required once feature size reaches 10 - 20 nm range.

This research focuses on using 111-V compounds, specifically indiumantimonide (lnSb), to supplement silicon CMOS technology. Due to its low bandgap and high …


Stability Criteria For Spontaneously Pulsing Gas Lasers, Pitak Chenkosol, Lee W. Casperson Sep 2009

Stability Criteria For Spontaneously Pulsing Gas Lasers, Pitak Chenkosol, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

Low-threshold spontaneous pulsations are known to occur in the output beams of certain high-gain gas lasers, and good agreement between the experimental observations and numerical models has been achieved. There have also been several analytical studies of threshold criteria for spontaneously pulsing lasers. However, the analytical studies are mostly not applicable to the lasers in which the pulsations have been observed. Stability criteria for high-gain gas lasers are derived in this study, and these criteria are compared with a previously modeled gas laser instability.


Apoptotic And Chemotherapeutic Properties Of Iron (Iii)-Salophene In An Ovarian Cancer Animal Model, Thilo S. Lange, Carolyn Mccourt, Rakesh K. Singh, Kyu Kwang Kim, Ajay P. Singh, Brian S. Luisi, Onur Alptürk, Robert M. Strongin, Laurent Brard Sep 2009

Apoptotic And Chemotherapeutic Properties Of Iron (Iii)-Salophene In An Ovarian Cancer Animal Model, Thilo S. Lange, Carolyn Mccourt, Rakesh K. Singh, Kyu Kwang Kim, Ajay P. Singh, Brian S. Luisi, Onur Alptürk, Robert M. Strongin, Laurent Brard

Chemistry Faculty Publications and Presentations

The cytotoxicity of organometallic compounds iron(III)-, cobalt(III)-, manganese(II)-, and copper(II)-salophene (-SP) on platinum-resistant ovarian cancer cell lines was compared. Fe-SP displayed selective cytotoxicity (IC(50) at ~1 muM) against SKOV-3 and OVCAR-3 cell lines while Co-SP caused cytotoxic effects only at higher concentrations (IC(50) at 60 muM) and Cu-SP effects were negligible. High cytotoxicity of Mn-SP (30-60 muM) appeared to be nonspecific because the Mn-chloride salt reduced cell viability similarly. The effect of Fe-SP at 1 muM proved to be ovarian cancer cell selective when compared to a panel of cell lines derived from different tumors. The first irreversible step in …


Influence Of Illumination On Dark Current In Charge-Coupled Device Imagers, Ralf Widenhorn, Ines Hartwig, Justin Charles Dunlap, Erik Bodegom Sep 2009

Influence Of Illumination On Dark Current In Charge-Coupled Device Imagers, Ralf Widenhorn, Ines Hartwig, Justin Charles Dunlap, Erik Bodegom

Physics Faculty Publications and Presentations

Thermal excitation of electrons is a major source of noise in charge-coupled-device (CCD) imagers. Those electrons are generated even in the absence of light, hence, the name dark current. Dark current is particularly important for long exposure times and elevated temperatures. The standard procedure to correct for dark current is to take several pictures under the same condition as the real image, except with the shutter closed. The resulting dark frame is later subtracted from the exposed image. We address the question of whether the dark current produced in an image taken with a closed shutter is identical to the …


Quantifying And Enforcing Two-Dimensional Symmetries In Scanning Probe Microscopy Images, Peter Moeck, Marius Toader, Mahmoud Abdel-Hafiez, Michael Hietschold Sep 2009

Quantifying And Enforcing Two-Dimensional Symmetries In Scanning Probe Microscopy Images, Peter Moeck, Marius Toader, Mahmoud Abdel-Hafiez, Michael Hietschold

Physics Faculty Publications and Presentations

The overall performance and correctness of the calibration of all kinds of traditional scanning probe microscopes can be assessed in a fully quantitative way by means of “crystallographic” processing of their two-dimensional (2D) images from samples with 2D periodic (and preferably highly symmetric) features. This is because crystallographic image processing results in two residual indices that quantify by how much the symmetry in a corresponding scanning probe microscopy image deviates from the symmetries of the possible plane groups of the periodic features of the sample. When a most probable plane symmetry group has been identified on the basis of crystallographic …


Interview With Rabbi Arthur Zuckerman, Shaarie Torah, 2009 (Audio), Arthur Zuckerman Aug 2009

Interview With Rabbi Arthur Zuckerman, Shaarie Torah, 2009 (Audio), Arthur Zuckerman

All Sustainability History Project Oral Histories

Interview of Rabbi Arthur Zuckerman by Austin Rosenfeld in NW Portland, Oregon on August 7th, 2009.

The interview index is available for download.


Fabrication Of Anisotropic Nanostructures On Solid Substrates For Applications As Optically Active Surfaces, Mohan Krishna Vattipalli Aug 2009

Fabrication Of Anisotropic Nanostructures On Solid Substrates For Applications As Optically Active Surfaces, Mohan Krishna Vattipalli

Dissertations and Theses

Analysis of the vibrational energy levels in molecules using Raman Spectroscopy is a popular analytical method amongst today's optical technologies. Unlike fluorescence microscopy, the Raman emission doesn't undergo the process of photobleaching, which leads to short lived signal collection. The only downside with this approach is the small absorption cross-section resulting in a low intensity of the emission signal. One of the approaches used to boost this weak signal is Surface Enhanced Raman Spectroscopy (SERS). My research efforts have been focused on how to create a novel SERS substrate with aligned patterns of Au/Ag nanoparticle deposited metals of a particular …


Interview With Angela Martin, Village Gardens, 2009 (Audio), Angela Martin Aug 2009

Interview With Angela Martin, Village Gardens, 2009 (Audio), Angela Martin

All Sustainability History Project Oral Histories

Interview of Angela Martin by Steve Jarosz at Village Gardens, Portland, Oregon on August 6th, 2009.

The interview index is available for download.


A Discrete Impulsive Model For Random Heating And Brownian Motion, John D. Ramshaw Aug 2009

A Discrete Impulsive Model For Random Heating And Brownian Motion, John D. Ramshaw

Physics Faculty Publications and Presentations

The energy of a mechanical system subjected to a random force with zero mean increases irreversibly and diverges with time in the absence of friction or dissipation. This random heating effect is usually encountered in phenomenological theories formulated in terms of stochastic differential equations, the epitome of which is the Langevin equation of Brownian motion. We discuss a simple discrete impulsive model that captures the essence of random heating and Brownian motion. The model may be regarded as a discrete analog of the Langevin equation, although it is developed ab initio. Its analysis requires only simple algebraic manipulations and elementary …


Climate Justice: Towards A Proactive Response To Social Inequities, Vivek Shandas Aug 2009

Climate Justice: Towards A Proactive Response To Social Inequities, Vivek Shandas

Institute for Sustainable Solutions Publications and Presentations

Discussions about climate change have taken center stage. Claims of 'carbon neutral', and strategies for calculating and mitigating green house gas emissions (GHGs) have become common place from Beaverton to Bali. The discourse on climate change, however, remains largely an environmental one, with increasingly precise definitions of parts per million, downscaling climate models, and regional assessments for reducing carbon dioxide (CO2) emissions. These discussions are essential for understanding connections between local sources of GHGs and global consequences of our actions. But health and equity are equally critical dimensions of climate change, although these dimensions have had only limited investigation. Regional …


Distribution Logistics Course, Miguel A. Figliozzi Aug 2009

Distribution Logistics Course, Miguel A. Figliozzi

TREC Final Reports

Commercial vehicle movements associated with the delivery of goods and services are currently experiencing a number of challenging problems. Carriers and fleet operations face congestion, a growing number of tolls, increasing service level demands, and in some cases opposition due to the externalities caused by freight traffic in urban areas. This course provided a greater understanding of the complex issues surrounding urban freight and logistics and it was relevant to graduate students in civil engineering, urban planning, and business programs.


Nanostructured Semiconductor Heterojunctions From Quantum Dot Layers, Rolf Könenkamp, Robert Campbell Word, Athavan Nadarajah Aug 2009

Nanostructured Semiconductor Heterojunctions From Quantum Dot Layers, Rolf Könenkamp, Robert Campbell Word, Athavan Nadarajah

Physics Faculty Publications and Presentations

We report the deposition of conformal thin layers of 10?50 nm thickness from II-VI quantum dot suspensions on ZnO nanowire substrates. Smooth polycrystalline films of high electronic quality can be obtained from CdSe quantum dots after annealing at moderate temperatures. The electronic properties are adequate for detector and solar cell applications. The growth and annealing temperatures permit deposition on light-weight and flexible substrates. Some elemental diffusion of Se across the CdSe/ZnO interface occurs in the film formation. A comparison with CdS/ZnO junctions indicates that the low Se diffusion rates are essential for efficient charge transfer.


National Urban Database And Access Portal Tool, Nudapt, Jason Ching, Michael Brown, Steven Burian, Fei Chen, Ron Cionco, Adel Hanna, Torrin Hultgren, Timothy Mcpherson, David J. Sailor, Haider Taha, David Williams Aug 2009

National Urban Database And Access Portal Tool, Nudapt, Jason Ching, Michael Brown, Steven Burian, Fei Chen, Ron Cionco, Adel Hanna, Torrin Hultgren, Timothy Mcpherson, David J. Sailor, Haider Taha, David Williams

Mechanical and Materials Engineering Faculty Publications and Presentations

Based on the need for advanced treatments of high resolution urban morphological features (e.g., buildings, trees) in meteorological, dispersion, air quality and human exposure modeling systems for future urban applications, a new project was launched called the National Urban Database and Access Portal Tool (NUDAPT). NUDAPT is sponsored by the U.S. Environmental Protection Agency (USEPA) and involves collaborations and contributions from many groups including federal and state agencies and from private and academic institutions here and in other countries. It is designed to produce and provide gridded fields of urban canopy parameters for various new and advanced descriptions of model …


Interview With Caitlin Blethen, Growing Gardens, 2009 (Audio), Caitlin Blethen Jul 2009

Interview With Caitlin Blethen, Growing Gardens, 2009 (Audio), Caitlin Blethen

All Sustainability History Project Oral Histories

Interview of Caitlin Blethen by Kristin Milner at Growing Gardens Organization Portland, Oregon on July 29th, 2009.

The interview index is available for download.


Interview With Rodney Bender, Growing Gardens, 2009 (Audio), Rodney Bender Jul 2009

Interview With Rodney Bender, Growing Gardens, 2009 (Audio), Rodney Bender

All Sustainability History Project Oral Histories

Interview of Rodney Bender by Sarah Roecker at Growing Gardens Portland, Oregon on July 29th, 2009.

The interview index is available for download.