Physical Sciences and Mathematics Commons^™

Interview With Bernard Smith, Full Of Life Farms, 2010 (Audio), Bernard Smith

All Sustainability History Project Oral Histories

Interview of Bernard Smith by Kyle Dykstra on February 28th, 2010.

The interview index is available for download.

Interview With Katy Kolker, Portland Fruit Tree Project, 2010 (Audio), Katy Kolker

All Sustainability History Project Oral Histories

Interview of Katy Kolker by Dan Stillinger in Portland, Oregon on February 27th, 2010.

The interview index is available for download.

Biologically Inspired Computing: The Darpa Synapse Program & The Hierarchical Temporal Memory, Dan Hammerstrom

Systems Science Friday Noon Seminar Series

This presentation provides an update on biologically inspired computation. In particular, it focuses on two important developments in this area, the DARPA SyNAPSE program (Systems of Neuromorphic Adaptive Plastic Scalable Electronics) and the HTM (Hierarchical Temporal Memory) being developed by Numenta.

The SyNAPSE Program’s ultimate goal is to build a low-power, compact electronic chip combining novel analog circuit design and a neuroscience-inspired architecture that can address a wide range of cognitive abilities: perception, planning, decision making and motor control. According to DARPA program manager Todd Hylton, “Our research progress in this area is unprecedented, No suitable electronic synaptic device that …

Interview With Allejandro Tecum, Adelante Mujeres, 2010 (Audio), Allejandro Tecum

All Sustainability History Project Oral Histories

Interview of Allejandro Tecum by Adam Villareal at Forest Grove, Oregon on February 25th, 2010.

The interview index is available for download.

Interview With David Beller, Mercy Corp Nw, 2010 (Audio), David Beller

All Sustainability History Project Oral Histories

Interview of David Beller by Kyle Koonce at Mercy Corp Portland, Oregon on February 25th, 2010.

The interview index is available for download.

Interview With Darrell Sanders, Cully Community Garden, 2010 (Audio), Darrell Sanders

All Sustainability History Project Oral Histories

Interview of Darrell Sanders by Jeremy Cohen in Portland, Oregon on February 20th, 2010.

The interview index is available for download.

Understanding Classification Decisions For Object Detection, Will Landecker, Michael David Thomure, Melanie Mitchell

Systems Science Friday Noon Seminar Series

Computer vision systems are traditionally tested in the object detection paradigm. In these experiments, a vision system is asked whether or not a specific object--for example an animal--occurs in a given image. A system that often answers correctly is said to be very accurate. In this talk, we will discuss some ambiguity that exists in this measure of accuracy. We will also propose a new measure of object-detection accuracy that addresses some of this ambiguity, and apply this measure to the hierarchical "standard model" of visual cortex.

Emissions Of Anaerobically Produced Methane By Trees, Andrew L. Rice, Christopher Lee Butenhoff, Martha J. Shearer, Doaa Teama, Todd N. Rosenstiel, M. A. K. Khalil

Physics Faculty Publications and Presentations

Recent studies indicate that plants may be a previously overlooked but significant source of atmospheric CH₄, though there is considerable disagreement on the mechanism of production. Our work sought to verify that woody deciduous trees grown under inundated conditions had the capacity for transporting CH₄ from an anaerobic subsurface to the atmosphere and to consider if such a source could be important globally. Here, we report results from a greenhouse mesocosm study that indicate significant emissions of anaerobically produced CH₄ transmitted to the atmosphere through broadleaf riparian tree species grown under flooded conditions. Using a leaf area normalized mean emission …

Microscopic Formulation Of The Zimm-Bragg Model For The Helix-Coil Transition, A. V. Badasyan, A. Giacometti, Y. S. Mamasakhlisov, V. F. Morozov, Albert S. Benight

Chemistry Faculty Publications and Presentations

A microscopic spin model is proposed for the phenomenological Zimm-Bragg model for the helix-coil transition in biopolymers. This model is shown to provide the same thermophysical properties of the original Zimm-Bragg model and it allows a very convenient framework to compute statistical quantities. Physical origins of this spin model are made transparent by an exact mapping into a one-dimensional Ising model with an external field. However, the dependence on temperature of the reduced external field turns out to differ from the standard one-dimensional Ising model and hence it gives rise to different thermophysical properties, despite the exact mapping connecting them. …

Segmentation Of Thermographic Images Of Hands Using A Genetic Algorithm, Payel Ghosh, Judith Gold, Melanie Mitchell

Computer Science Faculty Publications and Presentations

This paper presents a new technique for segmenting thermographic images using a genetic algorithm (GA). The individuals of the GA also known as chromosomes consist of a sequence of parameters of a level set function. Each chromosome represents a unique segmenting contour. An initial population of segmenting contours is generated based on the learned variation of the level set parameters from training images. Each segmenting contour (an individual) is evaluated for its fitness based on the texture of the region it encloses. The fittest individuals are allowed to propagate to future generations of the GA run using selection, crossover and …

Homocystamides Promote Free-Radical And Oxidative Damage To Proteins, Martha Sibrian-Vazquez, Jorge O. Escobedo, Soojin Lim, George K. Samoei, Robert M. Strongin

Chemistry Faculty Publications and Presentations

Elevated levels of homocysteine are associated with several major diseases. However, it is not clear whether homocysteine is a marker or a causative agent. The majority (ca. 80%) of the homocysteine present in humans is protein bound. The study of the posttranslational modification of proteins by homocysteine and its cyclic congener, homocysteine thiolactone, is emerging as an area of great current interest for unraveling the ongoing “mediator/marker controversy” [Jacobsen DW (2009) Clin Chem 55:1–2]. Interestingly, many of the pathologies associated with homocysteine are also linked to oxidative stress. In the current study, chemical evidence for a causal relationship between homocysteine-bound …

Oregon's Fish And Wildlife In A Changing Climate, Mark A. Hixon, Stanley V. Gregory, W. Douglas Robinson, C. Scott Baker, Harold P. Batchelder, Clinton Epps, Tiffany S. Garcia, Susan M. Haig, Ricardo M. Letelier, David A. Lytle, Bruce A. Menge, Jeffery C. Miller, David L.G. Noakes, William T. Peterson, James M. Rice, Steven S. Rumrill, Carl B. Schreck, Robert M. Suryan, Mark D. Sytsma, Angelicque E. White

Center for Lakes and Reservoirs Publications and Presentations

Chapter 7 in: The Oregon Climate Change Assessment Report

Oregon's fish and wildlife include animals on land, fish and other species in rivers and lakes, and various kinds of sea life in estuaries and coastal ocean. Oregon is one of the most ecologically diverse states in the country. The state’s robust biodiversity, some of which is already threatened or endangered -- inhabits complex and dynamic ecosystems that we have only begun to understand, let alone examine in terms of climate change.It is clear that the abundance and distribution of species are shifting already and will shift more rapidly as habitats …

Hydroacoustic Survey And Point Sampling Of Macrophytes In Diamond Lake 2009, Joseph Eilers, Benn Eilers, Mark D. Sytsma, Rich Miller

Center for Lakes and Reservoirs Publications and Presentations

MaxDepth Aquatics, Inc. was contracted to conduct a hydroacoustic survey of macrophyte distribution in Diamond Lake in 2009. The survey essentially repeated surveys conducted in 2002 and 2007, allowing for a detailed assessment of conditions in 2009 and comparisons among previous years. In addition, Portland State University was contracted to conduct a depth stratified random point sample survey of macrophyte species presence and absence. The point sample survey was similar to surveys conducted in 2005 and 2007. The results of the 2009 hydroacoustic survey showed that macrophytes were widely distributed throughout the lake at depths less than 8 meters, although …

Portland State University Climate Action Plan, 2010, Fletcher Beaudoin, Noelle Studer-Spevak

Campus Sustainability Office Publications, Reports and Presentations

In June 2007, Portland State University (PSU) joined this effort by signing the American College and University Presidents Climate Commitment (ACUPCC). The commitment challenged PSU to form a committee to oversee climate efforts, track carbon emissions, and develop a Climate Action Plan (CAP) to move toward carbon neutrality. This document fulfills the final requirement for ACUPCC and supports regional climate goals of partner agencies, such as those described in the 2009 City of Portland and Multnomah County Climate Action Plan.

A Virtual Visit To A Sustainable 2050, Robert Costanza

Institute for Sustainable Solutions Publications and Presentations

The article describes the situation in a virtual, sustainable world in 2050. Observations include stable global human population at 8 billion people, slightly decreasing material throughput of local and global economies with an average quality of life (QOL) index at 2% per year. It also notes the lower income gaps within and between countries, the return of global biodiversity and the problem with regards to the effects of climate change. It also adds the use of internal labor equivalent trading system (LETS).

Climate Change And Freshwater Resources In Oregon, Heejun Chang, Julie Jones

Institute for Sustainable Solutions Publications and Presentations

Climate change will affect various sectors of water resources in Oregon in the 21st century. The observed trends in streamflow show significant declines in September flow and, although not significant, increases in March flow in many transient rain-snow basins. These streamflow trends are associated with rising temperature and coincident declines in snowpack in spring in the latter half of the 20th century. While there are no distinct trends in high precipitation events, such events are associated with climate variability such as ENSO and PDO. Effects of ENSO and PDO are more pronounced at the beginning and end of the wet …

Symmetries Of The Central Vestibular System: Forming Movements For Gravity And A Three-Dimensional World, Gin Mccollum, Douglas A. Hanes

Gin McCollum

Intrinsic dynamics of the central vestibular system (CVS) appear to be at least partly determined by the symmetries of its connections. The CVS contributes to whole-body functions such as upright balance and maintenance of gaze direction. These functions coordinate disparate senses (visual, inertial, somatosensory, auditory) and body movements (leg, trunk, head/neck, eye). They are also unified by geometric conditions. Symmetry groups have been found to structure experimentally-recorded pathways of the central vestibular system. When related to geometric conditions in three-dimensional physical space, these symmetry groups make sense as a logical foundation for sensorimotor coordination.

Phase-Linking And The Perceived Motion During Off-Vertical Axis Rotation, Jan E. Holly, Scott J. Wood, Gin Mccollum

Gin McCollum

Human off-vertical axis rotation (OVAR) in the dark typically produces perceived motion about a cone, the amplitude of which changes as a function of frequency. This perception is commonly attributed to the fact that both the OVAR and the conical motion have a gravity vector that rotates about the subject. Little-known, however, is that this rotating-gravity explanation for perceived conical motion is inconsistent with basic observations about self-motion perception: (a) that the perceived vertical moves toward alignment with the gravito-inertial acceleration (GIA) and (b) that perceived translation arises from perceived linear acceleration, as derived from the portion of the GIA …

What Should Be Done With The Revenues From A Carbon Cap And Auction System?, Robert Costanza, Joshua C. Farley

Institute for Sustainable Solutions Publications and Presentations

In this article the author discusses the use of the revenues which can be generated from a carbon cap and auction system in the U.S. They believe that auction system will be politically feasible if all individuals share generated revenues equally. A significant fraction from the revenue should pay for related projects like researching and developing renewable energy in developing countries. The shareholders in this atmospheric commons should be both the current and future generations.

Creating A Sustainable And Desirable Future, Robert Costanza

Institute for Sustainable Solutions Publications and Presentations

The article suggests methods of social and economic reform as a means to counter environment impact of pollution resulting from dependence on fossil fuels.

The Search For Real, Integrative Solutions, Robert Costanza

Institute for Sustainable Solutions Publications and Presentations

The article presents the author's views on the inaugural issue of the journal. He states that the journal is aimed at building a shared vision in the society. He believes that one of the reasons for the society's inability to make progress is because of the academia, media, law and politics cast complex problems as polar opposites, which is known as argument culture that the journal aims to resolve.

Salt Marsh Zonal Migration And Ecosystem Service Change In Response To Global Sea Level Rise: A Case Study From An Urban Region, Rusty A. Feagin, M. Luisa Martinez, Gabriela Mendoza-Gonzalez, Robert Costanza

Institute for Sustainable Solutions Publications and Presentations

Coastal wetland plants are expected to respond to global sea level rise by migrating toward higher elevations. Housing, infrastructure, and other anthropogenic modifications are expected to limit the space available for this potential migration. Here, we explore the ecological and economic effects of projected Intergovernmental Panel on Climate Change (IPCC) 2007 report sea level changes at the plant community scale using the highest horizontal (1 m) and vertical (0.01 m) resolution data available, using a 6 x 6 km area as an example. Our findings show that salt marshes do not always lose land with increasing rates of sea level …

Hybridization And Postprocessing Techniques For Mixed Eigenfunctions, Bernardo Cockburn, Jay Gopalakrishnan, F. Li, Ngoc Cuong Nguyen, Jaume Peraire

Mathematics and Statistics Faculty Publications and Presentations

We introduce hybridization and postprocessing techniques for the Raviart–Thomas approximation of second-order elliptic eigenvalue problems. Hybridization reduces the Raviart–Thomas approximation to a condensed eigenproblem. The condensed eigenproblem is nonlinear, but smaller than the original mixed approximation. We derive multiple iterative algorithms for solving the condensed eigenproblem and examine their interrelationships and convergence rates. An element-by-element postprocessing technique to improve accuracy of computed eigenfunctions is also presented. We prove that a projection of the error in the eigenspace approximation by the mixed method (of any order) superconverges and that the postprocessed eigenfunction approximations converge faster for smooth eigenfunctions. Numerical experiments using …

Corrosion Behavior Of Copper Thin Films In Organic Hf-Containing Cleaning Solution For Semiconductor Applications, Nabil George Mistkawi, Makarem A. Hussein, Malgorzata Ziomek-Moroz, Shankar B. Rananavare

Chemistry Faculty Publications and Presentations

The corrosion behavior of electrochemically deposited copper thin films in deaerated and non-deaerated commercial cleaning solutions containing HF was investigated. Potentiodynamic polarization experiments were carried out to determine active, active–passive, passive, and transpassive regions. Corrosion rates were calculated from Tafel slopes. The addition of hydrogen peroxide to the solution and its influence on corrosion was also investigated by employing inductively coupled plasma-mass spectroscopy (ICP-MS) and X-ray photoelectron spectroscopy (XPS). The ICP-MS and potentiodynamic methods yielded comparable Cu dissolution rates. Surface analysis using atomic force microscopy and scanning electron microscopy, performed before and after the cleaning solution treatment, did not reveal …

Gaining Ground: Wetlands, Hurricanes, And The Economy: The Value Of Restoring The Mississippi River Delta, David Batker, Isabel De Torre, Robert Costanza, Paula Swedeen, John W. Day, Roelof Boumans, Kenneth Bagstad

Institute for Sustainable Solutions Publications and Presentations

This report shows conclusively that physical sustainability and delta expansion secures vast economic benefits locally and nationally. Within the context of the current financial crisis, investment in restoration secures short-term benefits of employment, income generation, greater ecosystem services and other economic benefits, and the long term goals of increased storm protection, greater oil and gas supply reliability and other economic benefits. A sustainable restoration of the Mississippi River Delta is a good investment with a high rate of return. Gaining ground is the most successful economic strategy for securing hurricane defenses and economic development.

A Class Of Discontinuous Petrov–Galerkin Methods. Ii. Optimal Test Functions, Leszek Demkowicz, Jay Gopalakrishnan

Mathematics and Statistics Faculty Publications and Presentations

We lay out a program for constructing discontinuous Petrov–Galerkin (DPG) schemes having test function spaces that are automatically computable to guarantee stability. Given a trial space, a DPG discretization using its optimal test space counterpart inherits stability from the well posedness of the undiscretized problem. Although the question of stable test space choice had attracted the attention of many previous authors, the novelty in our approach lies in the fact we identify a discontinuous Galerkin (DG) framework wherein test functions, arbitrarily close to the optimal ones, can be locally computed. The idea is presented abstractly and its feasibility illustrated through …

Study Of The Numerical Modeling Of The Temperature Dependence Of The Dark Current In Charge Coupled Devices, Ralf Widenhorn, Ionel Tunaru, Erik Bodegom, Dan A. Iordache

Physics Faculty Publications and Presentations

As it is well known, the classical works of the Dark Current Spectroscopy method allow - using some not too accurate theoretical relations, but huge numbers of dark current values for thousands of pixels - the evaluation of a reduced number of basic impurities parameters. Unlike these works, this paper tries to obtain--by means of some better approximations of the Shockley-Read-Hall (SRH) model--more information about the studied impurities, as well as the study of the compatibility of the used theoretical model SRH relative to the experimental data. In this manner, both the compatibility SRH model with the studied experimental data …

What Drives Academic Bioscientists: Money Or Values?, David E. Ervin, Sharmistha Nag, Hui Yang, Steven T. Buccola

Economics Faculty Publications and Presentations

The article determines the factors that drive academic bioscience to better understand the role of genetically engineered (GE) crops in the sustainability of U.S. agriculture. Some challenges brought about by GE crops in the U.S. farm sustainability include tracking and controlling water pollution, protecting against herbicide resistance and nitrogen fixation. Professional norms are also considered as a great factor driving the academic bioscience.

Genetically Engineering Crops For A Sustainable Agriculture, David E. Ervin, Rick Welsh

Economics Faculty Publications and Presentations

The article examines the role of genetically engineered (GE) crops in fostering a more sustainable agriculture. An overview of the National Academy of Sciences metal study of the impacts of GE crops on farm sustainability in the U.S. is given. The two types of GE crops are discussed, one which produces its own insecticide called insect resistant (IR) crops and the other is engineered to resist particular herbicides. An explanation for sustainable agriculture is also presented.

Characterization And Correction Of Dark Current In Compact Consumer Cameras, Justin Charles Dunlap, Erik Bodegom, Ralf Widenhorn

Physics Faculty Publications and Presentations

A study of dark current in digital imagers within consumer grade digital cameras is presented. Dark current is shown to vary with temperature, exposure time, and ISO setting. Further, dark current is shown to increase in successive images during a series of images. Consumer cameras are often designed to be as compact as possible and therefore the digital imagers within the camera frame are prone to heat generated by nearby elements within the camera body. It is the scope of this work to characterize the dark current in such cameras and to show that the dark current, in part due …