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Effects Of Experimental Greenhouse Warming On Phytoplankton And Zooplankton Communities In Fishless Alpine Ponds, Angela L. Strecker, Tyler P. Cobb, Rolf D. Vinebrooke Jul 2004

Effects Of Experimental Greenhouse Warming On Phytoplankton And Zooplankton Communities In Fishless Alpine Ponds, Angela L. Strecker, Tyler P. Cobb, Rolf D. Vinebrooke

Environmental Science and Management Faculty Publications and Presentations

The impacts of global warming on aquatic ecosystems are expected to be most pronounced at higher trophic levels in cold-water environments. Therefore, we hypothesized that wanning of fishless alpine ponds would suppress large-bodied consumers (e.g., cladocerans, copepods) and stimulate fast-growing microorganisms (e.g., phytoflagellates, rotifers), thereby altering the community composition and total abundance of zooplankton and phytoplankton. This hypothesis was tested using three blocks of four experimental mesocosms (1000-liter capacity) that were located next to alpine ponds in Banff National Park, Canada. Each block received unfiltered pond water and sediment from a pond following ice out in June 2000. A warming …


Green River Ce-Qual-W2 Project: A Hydrodynamic And Water Quality Study Of The Green River King County, Washington, Tim Kraft, Robert Leslie Annear, Chris Berger, Scott A. Wells Jul 2004

Green River Ce-Qual-W2 Project: A Hydrodynamic And Water Quality Study Of The Green River King County, Washington, Tim Kraft, Robert Leslie Annear, Chris Berger, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

This report describes the data processing and model calibration performed for a hydrodynamic and water quality model of the Green River, located in King County, Washington. Figure 1 shows the location of the river, and the limits of the section of river that was modeled.

The Green River flows from its headwaters in the Cascade Mountain foothills through the King County, Washington communities of Auburn, Kent, and Tukwila before discharging into the Duwamish River. Two sections of the river were modeled in this project. The Middle Green River begins in the Cascade Mountain foothills east of Tacoma, and continues downstream …


Periodic Atlas: Mapping School & Society, Alton Straub Jul 2004

Periodic Atlas: Mapping School & Society, Alton Straub

Institute of Metropolitan Studies Publications

When communities change economically, culturally, and politically, few institutions are expected to adapt and respond as quickly as are public schools. In part, this expectation is justifiable. Free and compulsory education is a cornerstone of modern democracy. But do we expect too much? Should our public schools, whose funding we always seem to begrudge, be expected to overcome issues of poverty, race, and language that other societal institutions struggle with unsuccessfully? If we leave no child behind, if we save our struggling public schools, if our students achieve, are we addressing those issues in the most efficient and fundamental way? …


Teabag: A Debugger For Curry, Stephen Lee Johnson Jul 2004

Teabag: A Debugger For Curry, Stephen Lee Johnson

Dissertations and Theses

This thesis describes TeaBag, which is a debugger for functional logic computations. TeaBag is an accessory of a virtual machine currently under development. A distinctive feature of this machine is its operational completeness of computations, which places novel demands on a debugger. This thesis describes the features of TeaBag, in particular the handling of non-determinism, the ability to control nondeterministic steps, to remove context information, to toggle eager evaluation, and to set breakpoints on both functions and terms. This thesis also describes TeaBag's architecture and its interaction with the associated virtual machine. Finally, some debugging sessions of defective programs are …


Approximate Thermodynamic State Relations In Partially Ionized Gas Mixtures, John D. Ramshaw Jun 2004

Approximate Thermodynamic State Relations In Partially Ionized Gas Mixtures, John D. Ramshaw

Physics Faculty Publications and Presentations

Thermodynamic state relations for mixtures of partially ionized nonideal gases are often approximated by artificially partitioning the mixture into compartments or subvolumes occupied by the pure partially ionized constituent gases, and requiring these subvolumes to be in temperature and pressure equilibrium. This intuitively reasonable procedure is easily shown to reproduce the correct thermal and caloric state equations for a mixture of neutral nonionized ideal gases. The purpose of this paper is to point out that (a) this procedure leads to incorrect state equations for a mixture of partially ionized ideal gases, whereas (b) the alternative procedure of requiring that the …


Sediment Nutrient Accumulation And Nutrient Availability In Two Tidal Freshwater Marshes Along The Mattaponi River, Virginia, Usa, Jennifer L. Morse, J. Patrick Megonigal, Mark R. Walbridge Jun 2004

Sediment Nutrient Accumulation And Nutrient Availability In Two Tidal Freshwater Marshes Along The Mattaponi River, Virginia, Usa, Jennifer L. Morse, J. Patrick Megonigal, Mark R. Walbridge

Environmental Science and Management Faculty Publications and Presentations

Sediment deposition is the main mechanism of nutrient delivery to tidal freshwater marshes (TFMs). We quantified sediment nutrient accumulation in TFMs upstream and downstream of a proposed water withdrawal project on the Mattaponi River, Virginia. Our goal was to assess nutrient availability by comparing relative rates of carbon (C), nitrogen (N), and phosphorus (P) accumulated in sediments with the C, N, and P stoichiometries of surface soils and above ground plant tissues. Surface soil nutrient contents (0.60–0.92% N and 0.09–0.13% P) were low but within reported ranges for TFMs in the eastern US. In both marshes, soil nutrient pools and …


Impactos Da Exploração Madeireira E Do Fogo Em Florestas De Transição Da Amazônia Legal, André Luiz Silva Monteiro, Carlos Moreira De Souza Jr., Paulo Gonçalves Barreto, Frank Leone De Sousa Pantoja, Jeffrey J. Gerwing Jun 2004

Impactos Da Exploração Madeireira E Do Fogo Em Florestas De Transição Da Amazônia Legal, André Luiz Silva Monteiro, Carlos Moreira De Souza Jr., Paulo Gonçalves Barreto, Frank Leone De Sousa Pantoja, Jeffrey J. Gerwing

Environmental Science and Management Faculty Publications and Presentations

A exploração de madeira e os incendios têm causado severos danos a florestas na Amazonia. Faltavam estudos sobre os impactos da exploração e do fogo em florestas de transição entre a floresta ombrófila densa e florestas de cerrado. Neste estudo, foram quantificados os impactos de várias intensidades de exploração madeireira e fogo na estrutura e composição de florestas de transição -- em termos de densidade de árvores e de cipós, cobertura do dossel e perturbação do solo e da biomassa acima do solo -- na regiao de Claudia, Mato Grosso. O estudo foi conduzido em 12 propriedades, através de inventários …


Prediction Of Growth Factor Effects On Engineered Cartilage Composition Using Deterministic And Stochastic Modeling, Sean S. Kohles, Asit K. Saha, J. (Jagannath) Mazumdar Jun 2004

Prediction Of Growth Factor Effects On Engineered Cartilage Composition Using Deterministic And Stochastic Modeling, Sean S. Kohles, Asit K. Saha, J. (Jagannath) Mazumdar

Mechanical and Materials Engineering Faculty Publications and Presentations

In the design of engineered tissues, guided balance of biomaterial degeneration with tissue synthesis offers refined control of construct development. The objective of this study was to develop a mathematical model that describes the steady state metabolism of extracellular matrix molecules (ECM: glycosaminoglycan and collagen) in an engineered cartilage construct taking into account localized environmental changes that may arise because of the application of growth factors. The variable effects of growth factors were incorporated in the form of random noise rather than the difference in rates of synthesis and catabolism. Thus, the frequency of ECM accumulation for each matrix molecule …


Fundamental Conditions For The Evolution Of Altruism: Towards A Unification Of Theories, Jeffrey Alan Fletcher May 2004

Fundamental Conditions For The Evolution Of Altruism: Towards A Unification Of Theories, Jeffrey Alan Fletcher

Dissertations and Theses

In evolutionary theory the existence of self-sacrificing cooperative traits poses a problem that has engendered decades of debate. The principal theories of the evolution of altruism are inclusive fitness, reciprocal altruism, and multilevel selection. To provide a framework for the unification of these apparently disparate theories, this dissertation identifies two fundamental conditions required for the evolution of altruism: 1) non-zero-sum fitness benefits for cooperation and 2) positive assortment among altruistic behaviors. I demonstrate the underlying similarities in these three theories in the following two ways.

First, I show that the game-theoretic model of the prisoner’s dilemma (PD) is inherent to …


Toward A Sound Integration Of Isabelle With A Combined Decision Procedure, Tom Harke May 2004

Toward A Sound Integration Of Isabelle With A Combined Decision Procedure, Tom Harke

Computer Science Faculty Publications and Presentations

I present work on a project to integrate Isabelle, an extremely versatile interactive proof assistant, with a combined decision procedure, the Cooperating Validity Checker (CVC). Isabelle is sound and flexible, however it is often tedious to use. CVC is fully automatic, but only handles decision problems expressible over a relatively weak set of theories including linear arithmetic, uninterpreted functions, data types, and firstorder quantifier-free logic. My goal is to increase the amount of automation in Isabelle, by making it use CVC as an oracle for such problems, but without compromising Isabelle’s soundness.

In this paper I report on the progress …


An Integrated Aquatic Vegetation Management Plan For Blue Lake, Fairview, Oregon, Mary Pfauth, Mark Sytsma May 2004

An Integrated Aquatic Vegetation Management Plan For Blue Lake, Fairview, Oregon, Mary Pfauth, Mark Sytsma

Center for Lakes and Reservoirs Publications and Presentations

Blue Lake, located in Fairview, is on the 1998 Oregon Department of Environmental Quality (ODEQ) 303(d) list of water quality impaired water bodies for violating the upper pH standard (8.5) and supporting abundant aquatic weeds and alge. The lake is eutrophic and has high algal productivity, especially in mid to late summer. Curlyleaf pondweed, a non-native, invasive aquatic plant species, restricts access to and use of Blue Lake by humans. Human uses of the lake which have been impaired including boating, water skiing, fishing, and swimming. Development of the current Integrated Aquatic Vegetation Management Plan was driven by the need …


Waldo Lake Research In 2003, Mark D. Sytsma, John Rueter, Richard Petersen, Roy Koch, Scott A. Wells, Rich Miller, Laura Johnson, Robert Leslie Annear May 2004

Waldo Lake Research In 2003, Mark D. Sytsma, John Rueter, Richard Petersen, Roy Koch, Scott A. Wells, Rich Miller, Laura Johnson, Robert Leslie Annear

Civil and Environmental Engineering Faculty Publications and Presentations

This report summarizes the first year of an effort to develop a more complete understanding of the physical, chemical, and biological characteristics that drive the ecological processes of Waldo Lake. Modern limnology recognizes the importance of watershed processes as well as in- lake processes in lake ecosystem functioning. Therefore, the approach included consideration of watershed hydrology and forcing functions that determine hydrodynamics of the system as well physical and chemical factors that may be important in regulating primary production in the lake. Data collected since 1998 was summarized and bathymetry of the basin was mapped using state-of-the-art digital depth sounding …


Portland State Magazine, Portland State University. Office Of University Communications May 2004

Portland State Magazine, Portland State University. Office Of University Communications

Portland State Magazine

PSU’s alumni magazine, published 2-3 times a year. In this issue: Professor Michael Toth writes about the unique perspective of his discipline; College of Engineering and Computer Science makes a giant leap forward with the help of a generous gift; an unprecedented collection of contemporary Native American art is the focal point of a new center on campus; education alumni raise the bar for the children who are wards of the state; Diane Rulien ’86 directs a new museum and gallery devoted to 3-D photography; and more.


Applying The Transtheoretical Model To Cigarette Smoking By Pregnant And Parenting Adolescent Females, Barbara Mary Sussex Apr 2004

Applying The Transtheoretical Model To Cigarette Smoking By Pregnant And Parenting Adolescent Females, Barbara Mary Sussex

Dissertations and Theses

An unacceptably high number of pregnant and parenting adolescent females smoke cigarettes, and the majority who quit during pregnancy relapse within six months postpartum. This dissertation examined measures from the Transtheoretical Model of Change (TMC) and variables associated with smoking behavior in a population of pregnant and parenting females 18 years-of-age and under. Data were from the baseline survey of 245 young women enrolled in a three-year randomized controlled trial through a teen parent program in Portland, Oregon. The objectives were: 1) to investigate whether factors identified in the literature as associated with initiating and quitting smoking were associated with …


Willamette River Basin Temperature Tmdl Model: Model Scenarios, Robert Leslie Annear, Michael Lee Mckillip, Sher Jamal Khan, Chris Berger, Scott A. Wells Apr 2004

Willamette River Basin Temperature Tmdl Model: Model Scenarios, Robert Leslie Annear, Michael Lee Mckillip, Sher Jamal Khan, Chris Berger, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

The State of Oregon Department of Environmental Quality (DEQ) is developing a TMDL for temperature in the Willamette River basin shown in Figure 1. The study area included the Willamette River and all major tributaries (except the Tualatin River where a TMDL process was already concluded). A large section of the Columbia River was also modeled to provide adequate boundary representation of tidal flows in the lower Willamette River. The Willamette River below the Oregon City Falls in the Portland metropolitan area has a typical diurnal tidal range of 1 m. The development of a dynamic model of temperature and …


Faculty Senate Monthly Packet March 2004, Portland State University Faculty Senate Mar 2004

Faculty Senate Monthly Packet March 2004, Portland State University Faculty Senate

Faculty Senate Monthly Packets

The March 2004 Monthly packet includes the March agenda and appendices and the Faculty Senate minutes and attachments from the meeting held February 2004.


Mapping The Small Arms Trade: Insights From Social Network Analysis, David Todd Kinsella Mar 2004

Mapping The Small Arms Trade: Insights From Social Network Analysis, David Todd Kinsella

Political Science Faculty Publications and Presentations

In recent years, researchers have increasingly turned their attention to the proliferation of small arms, a transnational trade amounting to over $7 billion in value during 2002. Small arms are difficult to track and are not the stuff of military parades, but they are immensely destructive. The trade in small arms should be understood not as a market but as a network, one that shares some important properties with networked forms of organization studied by sociologists. I make this argument and then employ quantitative methods developed for the study of social networks in an effort to show the basic structure …


Faculty Senate Monthly Packet February 2004, Portland State University Faculty Senate Feb 2004

Faculty Senate Monthly Packet February 2004, Portland State University Faculty Senate

Faculty Senate Monthly Packets

The February 2004 Monthly packet includes the February agenda and appendices and the Faculty Senate minutes and attachments from the meeting held January 2004.


The Biodiversity And Biogeochemistry Of Cryoconite Holes From Mcmurdo Dry Valley Glaciers, Antarctica, Dorota L. Porazinska, Andrew G. Fountain, Thomas H. Nylen, Martyn Tranter, Ross A. Virginia, Diana H. Wall Feb 2004

The Biodiversity And Biogeochemistry Of Cryoconite Holes From Mcmurdo Dry Valley Glaciers, Antarctica, Dorota L. Porazinska, Andrew G. Fountain, Thomas H. Nylen, Martyn Tranter, Ross A. Virginia, Diana H. Wall

Geography Faculty Publications and Presentations

Once thought of as inert, ice has been increasingly recognized as a habitat suitable for life. The landscape of the MCMurdo Dry Valleys (MCM) of Antarctica is dominated by glaciers, and glacier melt is the primary water source for life in soils, streams, and lakes. The glaciers, despite their cold and lifeless appearance, offer functioning habitats for life. The major objective of this study was to examine biogeochemical characteristics of miniecosystems present in cryoconite holes and to determine links to other components (soils, streams, and lakes) of the dry valley landscape. We examined cryoconite holes from 5 glaciers spanning the …


Projecting Range Expansion Of Invasive European Green Crabs (Carcinus Maenas) To Alaska: Temperature And Salinity Tolerance Of Larvae, Anson Hines, Greg Ruiz, Natasha Gray Hitchcock, Catherine E. De Rivera Feb 2004

Projecting Range Expansion Of Invasive European Green Crabs (Carcinus Maenas) To Alaska: Temperature And Salinity Tolerance Of Larvae, Anson Hines, Greg Ruiz, Natasha Gray Hitchcock, Catherine E. De Rivera

Environmental Science and Management Faculty Publications and Presentations

The European Green Crab (Carcinus maenas) is a global invader, successfully colonizing many world regions and having significant ecological and economic impacts. The Green Crab colonized western North America in the late 1980s, spreading primarily northward from the initial establishment in San Francisco Bay to several other bays in northern California, Oregon, and Washington. Initial analysis, based largely upon temperature tolerance of postlarval crabs, suggests Green Crabs will continue to spread and become established throughout much of Alaska. However, establishment of self-sustaining populations in Alaska may be restricted by environmental conditions for reproduction and larval development, instead of the broad …


Climatology Of Katabatic Winds In The Mcmurdo Dry Valleys, Southern Victoria Land, Antarctica, Thomas H. Nylen, Andrew G. Fountain, Peter T. Doran Jan 2004

Climatology Of Katabatic Winds In The Mcmurdo Dry Valleys, Southern Victoria Land, Antarctica, Thomas H. Nylen, Andrew G. Fountain, Peter T. Doran

Geography Faculty Publications and Presentations

Katabatic winds dramatically affect the climate of the McMurdo dry valleys, Antarctica. Winter wind events can increase local air temperatures by 30°C. The frequency of katabatic winds largely controls winter (June to August) temperatures, increasing 1°C per 1% increase in katabatic frequency, and it overwhelms the effect of topographic elevation (lapse rate). Summer katabatic winds are important, but their influence on summer temperature is less. The spatial distribution of katabatic winds varies significantly. Winter events increase by 14% for every 10 km up valley toward the ice sheet, and summer events increase by 3%. The spatial distribution of katabatic frequency …


The Changing Role Of Non-Co2 Greenhouse Gases, M. A. K. Khalil Jan 2004

The Changing Role Of Non-Co2 Greenhouse Gases, M. A. K. Khalil

Physics Faculty Publications and Presentations

During the last century, the concentrations of several greenhouse gases have increased considerably - most notably carbon dioxide, methane and nitrous oxide. In addition, new, entirely man-made gases have been put into the atmosphere that also cause the greenhouse effect; these include the chlorofluorocarbons. Calculations have shown that during the last century the non-CO₂ greenhouse gases could together be almost as effective as the increase of carbon dioxide in causing global warming. These and similar gases were therefore included in the Kyoto Protocol to develop a comprehensive plan for controlling potentially unfavorable climatic change. Studies show however that the other …


Reconstructability Analysis With Fourier Transforms, Martin Zwick Jan 2004

Reconstructability Analysis With Fourier Transforms, Martin Zwick

Complex Systems Faculty Publications and Presentations

Fourier methods used in two‐ and three‐dimensional image reconstruction can be used also in reconstructability analysis (RA). These methods maximize a variance‐type measure instead of information‐theoretic uncertainty, but the two measures are roughly collinear and the Fourier approach yields results close to that of standard RA. The Fourier method, however, does not require iterative calculations for models with loops. Moreover, the error in Fourier RA models can be assessed without actually generating the full probability distributions of the models; calculations scale with the size of the data rather than the state space. State‐based modeling using the Fourier approach is also …


Bulletin: General Catalog Issue 2004-2005, Portland State University Jan 2004

Bulletin: General Catalog Issue 2004-2005, Portland State University

Bulletin & Curriculum Change Documents

No abstract provided.


Analysis Of A Multigrid Algorithm For Time Harmonic Maxwell Equations, Jay Gopalakrishnan, Joseph E. Pasciak, Leszek Demkowicz Jan 2004

Analysis Of A Multigrid Algorithm For Time Harmonic Maxwell Equations, Jay Gopalakrishnan, Joseph E. Pasciak, Leszek Demkowicz

Mathematics and Statistics Faculty Publications and Presentations

This paper considers a multigrid algorithm suitable for efficient solution of indefinite linear systems arising from finite element discretization of time harmonic Maxwell equations. In particular, a "backslash" multigrid cycle is proven to converge at rates independent of refinement level if certain indefinite block smoothers are used. The method of analysis involves comparing the multigrid error reduction operator with that of a related positive definite multigrid operator. This idea has previously been used in multigrid analysis of indefinite second order elliptic problems. However, the Maxwell application involves a nonelliptic indefinite operator. With the help of a few new estimates, the …


Decentralized Control Of Vehicle Formations, Gerardo Lafferriere, Anca Williams, John S. Caughman Iv, J. J. P. Veerman Jan 2004

Decentralized Control Of Vehicle Formations, Gerardo Lafferriere, Anca Williams, John S. Caughman Iv, J. J. P. Veerman

Mathematics and Statistics Faculty Publications and Presentations

This paper investigates a method for decentralized stabilization of vehicle formations using techniques from algebraic graph theory. The vehicles exchange information according to a pre-specified communication digraph, G. A feedback control is designed using relative information between a vehicle and its in-neighbors in G. We prove that a necessary and sufficient condition for an appropriate decentralized linear stabilizing feedback to exist is that G has a rooted directed spanning tree. We show the direct relationship between the rate of convergence to formation and the eigenvalues of the (directed) Laplacian of G. Various special situations are discussed, including …


An Overview Of Reconstructability Analysis, Martin Zwick Jan 2004

An Overview Of Reconstructability Analysis, Martin Zwick

Complex Systems Faculty Publications and Presentations

This paper is an overview of reconstructability analysis (RA), a discrete multivariate modeling methodology developed in the systems literature; an earlier version of this tutorial is Zwick (2001). RA was derived from Ashby (1964), and was developed by Broekstra, Cavallo, Cellier Conant, Jones, Klir, Krippendorff, and others (Klir, 1986, 1996). RA resembles and partially overlaps log‐line (LL) statistical methods used in the social sciences (Bishop et al., 1978; Knoke and Burke, 1980). RA also resembles and overlaps methods used in logic design and machine learning (LDL) in electrical and computer engineering (e.g. Perkowski et al., 1997). Applications of RA, like …


Calibrating An Intracranial Pressure Dynamics Model With Clinical Data - A Progress Report, Wayne W. Wakeland, James Mcnames, Brahm Goldstein Jan 2004

Calibrating An Intracranial Pressure Dynamics Model With Clinical Data - A Progress Report, Wayne W. Wakeland, James Mcnames, Brahm Goldstein

Complex Systems Faculty Publications and Presentations

We describe the calibration of a computer model of intracranial pressure (ICP) dynamics to correspond with annotated clinical data taken from a patient being treated for elevated ICP due to a traumatic brain injury. The research protocol employed during treatment includes adjusting the elevation of the head of the bed, adjusting the ventilator settings to induce mild hyperventilation and hypoventilation, and adjusting the height of the cerebrospinal fluid drainage system. The model behavior corresponds to the experimental data quite well in the case of the changing the head of the bed, but less well in the case of changing the …


Reconstructability Analysis: Theory And Applications [Editorial Introduction], Martin Zwick, Guangfu Shu, Yi Lin Jan 2004

Reconstructability Analysis: Theory And Applications [Editorial Introduction], Martin Zwick, Guangfu Shu, Yi Lin

Complex Systems Faculty Publications and Presentations

Reconstructability analysis (RA) dates back to the pioneering work of Ashby in the mid-1960s. In the 1970s and 1980s, RA was the subject of very active research in the systems community. It receded for a time as a focus of activity, but the special issue of the International Journal of General Systems in 1996 on the General Systems Problem Solver and the special IJGS issue in 2000 on Reconstructability Analysis in China marked the renewal of interest in this area. The current volume is part of this resurgence of activity. It collects together papers from the group at Portland State …


A Software Architecture For Reconstructability Analysis, Kenneth Willett, Martin Zwick Jan 2004

A Software Architecture For Reconstructability Analysis, Kenneth Willett, Martin Zwick

Complex Systems Faculty Publications and Presentations

Software packages for reconstructability analysis (RA), as well as for related log linear modeling, generally provide a fixed set of functions. Such packages are suitable for end‐users applying RA in various domains, but do not provide a platform for research into the RA methods themselves. A new software system, Occam3, is being developed which is intended to address three goals which often conflict with one another to provide: a general and flexible infrastructure for experimentation with RA methods and algorithms; an easily‐configured system allowing methods to be combined in novel ways, without requiring deep software expertise; and a system which …