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Articles 4801 - 4830 of 6910
Full-Text Articles in Entire DC Network
The Role Of Water And Other Resources In The Invasion Of Rubus Armeniacus In Pacific Northwest Ecosystems, Joshua Sundance Caplan
The Role Of Water And Other Resources In The Invasion Of Rubus Armeniacus In Pacific Northwest Ecosystems, Joshua Sundance Caplan
Dissertations and Theses
The factors influencing the invasive success of Rubus armeniacus (Himalayan blackberry) in the Pacific Northwest of North America are only partly understood, but have important implications for its management and for our understanding of the processes driving invasive plant proliferation in regions with seasonally fluctuating resources. I identified patterns of R. armeniacus occurrence and growth under widely ranging soil and light conditions in western Oregon. I found that light availability was a primary determinant of R. armeniacus occurrence and growth. I also found that R. armeniacus was tolerant of a wide range of soil conditions, notably coarse texture, and could …
Studies Of Dna Hybridization Reactions And Applications In Genetic Assays, Fidelis Manyanga
Studies Of Dna Hybridization Reactions And Applications In Genetic Assays, Fidelis Manyanga
Dissertations and Theses
The intent of this study was to investigate two fundamental aspects of short DNA duplex stability and how that stability differs for duplex molecules consisting of either all perfect match Watson/Crick base pairs or a mixture of perfect match Watson/Crick base pairs and mismatch base pairs. Theoretical and experimental investigations of the origins of the nucleation term in the free energy of DNA duplex formation were revisited. Thermodynamic parameters (ΔG, ΔH, Δ S and Tm) of short DNA/DNA duplexes ranging in length from 6 to 35 base pairs were systematically evaluated by Differential Scanning Calorimetry …
Nanometrology Device Standards For Scanning Probe Mmicroscopes And Processes For Their Fabrication And Use, Peter Moeck
Nanometrology Device Standards For Scanning Probe Mmicroscopes And Processes For Their Fabrication And Use, Peter Moeck
Physics Faculty Publications and Presentations
Nanometrology device standards and methods for fabricating and using such devices in conjunction With scanning probe microscopes are described. The fabrication methods comprise: (1) epitaxial growth that produces nanometer sized islands of knoWn morphology, structural, morphological and chemical stability in typical nanometrology environments, and large height-to-width nano-island aspect ratios, and (2) marking suitable crystallographic directions on the device for alignment With a scanning direction.
Faculty Senate Monthly Packet January 2009, Portland State University Faculty Senate
Faculty Senate Monthly Packet January 2009, Portland State University Faculty Senate
Faculty Senate Monthly Packets
The January 2009 Monthly packet includes the January agenda and appendices and the Faculty Senate minutes and attachments from the meeting held January 2009
Winter Precipitation Intensity And Enso/Pdo Variability In The Willamette Valley Of Oregon, Sarah Praskievicz, Heejun Chang
Winter Precipitation Intensity And Enso/Pdo Variability In The Willamette Valley Of Oregon, Sarah Praskievicz, Heejun Chang
Geography Faculty Publications and Presentations
There is growing concern about the effects of inter-annual climatic variability, such as the El-Niño Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO), on regional hydrology and water resources. We analyzed patterns of wintertime precipitation intensity, using both simple intensity and number of heavy precipitation days per year, for eight stations in northwestern Oregon’s Willamette Valley for the period 1972–2006, and examined the separate and combined influence of ENSO and PDO on precipitation intensity. The analysis was accomplished using Kendall’s tau and analysis of variance (ANOVA) to determine differences in precipitation intensity among combinations of positive and negative ENSO …
Beyond Gdp: The Need For New Measures Of Progress, Robert Costanza, Maureen Hart, John Talberth, Stephen Posner
Beyond Gdp: The Need For New Measures Of Progress, Robert Costanza, Maureen Hart, John Talberth, Stephen Posner
Institute for Sustainable Solutions Publications and Presentations
This paper is a call for better indicators of human well-being in nations around the world. We critique the inappropriate use of Gross Domestic Product (GDP) as a measure of national well-being, something for which it was never designed. We also question the idea that economic growth is always synonymous with improved well-being. Useful measures of progress and well-being must be measures of the degree to which society?s goals (i.e., to sustainably provide basic human needs for food, shelter, freedom, participation, etc.) are met, rather than measures of the mere volume of marketed economic activity, which is only one means …
Toward A New Sustainable Economy, Robert Costanza
Toward A New Sustainable Economy, Robert Costanza
Institute for Sustainable Solutions Publications and Presentations
The current financial meltdown is the result of under-regulated markets built on an ideology of free market capitalism and unlimited economic growth. The fundamental problem is that the underlying assumptions of this ideology are not consistent with what we now know about the real state of the world. The financial world is, in essence, a set of markers for goods, services, and risks in the real world and when those markers are allowed to deviate too far from reality, ?adjustments? must ultimately follow and crisis and panic can ensue. To solve this and future financial crisis requires that we reconnect …
Annual Faculty Senate Minutes October 2009 - June 2010, Portland State University Faculty Senate
Annual Faculty Senate Minutes October 2009 - June 2010, Portland State University Faculty Senate
Annual Compilations of the Faculty Senate Minutes (Minutes Only)
Minutes of the Faculty Senate for October 2009 to June 2010.
Dark Current Behavior In Dslr Cameras, Justin Charles Dunlap, Oleg Sostin, Ralf Widenhorn, Erik Bodegom
Dark Current Behavior In Dslr Cameras, Justin Charles Dunlap, Oleg Sostin, Ralf Widenhorn, Erik Bodegom
Physics Faculty Publications and Presentations
Digital single-lens reflex (DSLR) cameras are examined and their dark current behavior is presented. We examine the influence of varying temperature, exposure time, and gain setting on dark current. Dark current behavior unique to sensors within such cameras is observed. In particular, heat is trapped within the camera body resulting in higher internal temperatures and an increase in dark current after successive images. We look at the possibility of correcting for the dark current, based on previous work done for scientific grade imagers, where hot pixels are used as indicators for the entire chip?s dark current behavior. Standard methods of …
Cartograms, Crime And Location Quotients, Martin A. Andresen, Kathryn Wuschke, J. Bryan Kinney, Patricia Brantingham, Paul J. Brantingham
Cartograms, Crime And Location Quotients, Martin A. Andresen, Kathryn Wuschke, J. Bryan Kinney, Patricia Brantingham, Paul J. Brantingham
Criminology and Criminal Justice Faculty Publications and Presentations
Visualizing spatial information has a long history in the field of cartography. Though there are generally accepted forms of spatial data visualization to represent different types of spatial data, the interpretation of the resulting maps tends to be subjective at best and incorrect, at worst. Cartograms are an increasingly popular form of spatial data visualization, recently applied in political and epidemiological analyses in an attempt to better represent the spatial data under analysis. We use the cartogram procedure to map crime rates and location quotients. Using this visualization approach, we are able to show the usefulness of cartograms to represent …
Classical Search And Quantum Search Algorithms For Synthesis Of Quantum Circuits And Optimization Of Quantum Oracles, Sazzad Hossain
Classical Search And Quantum Search Algorithms For Synthesis Of Quantum Circuits And Optimization Of Quantum Oracles, Sazzad Hossain
Dissertations and Theses
We observe an enormous increase in the computational power of digital computers. This was due to the revolution in manufacturing processes and controlling semiconductor structures on submicron scale, ultimately leading to the control of individual atoms. Eventually, the classical electric circuits encountered the barrier of quantum mechanics and its effects. However, the laws of quantum mechanics can be also used to produce computational devices that lead to extraordinary speed increases over classical computers. Thus quantum computing becomes a very promising and attractive research area. The Computer Aided Design for Quantum circuits becomes an essential ingredient for such emerging research which …
The Nature Of People's Perceptions Of Wolves, Laura Briana Nobel
The Nature Of People's Perceptions Of Wolves, Laura Briana Nobel
Dissertations and Theses
European immigrants once regarded wolves as the "devil in disguise" (Lopez, 1978, p.40). With our growing awareness of other cultural perspectives and flourishing body of scientific knowledge with regard to wolves' behavior, our perceptions of wolves have become more complicated and nuanced. Our collective awareness of the environment in which we live also gathers complexity. I examine these issues in this study. Wolves are returning to Oregon. The arrival of wolf B-45 in 1999 heralded the beginning of the return of wild wolves to Oregon. More wolves are expected to cross the border as young sub-adults disperse from the growing …
Quantum Inductive Learning And Quantum Logic Synthesis, Martin Lukac
Quantum Inductive Learning And Quantum Logic Synthesis, Martin Lukac
Dissertations and Theses
Since Quantum Computer is almost realizable on large scale and Quantum Technology is one of the main solutions to the Moore Limit, Quantum Logic Synthesis (QLS) has become a required theory and tool for designing Quantum Logic Circuits. However, despite its growth, there is no any unified aproach to QLS as Quantum Computing is still being discovered and novel applications are being identified.
The intent of this study is to experimentally explore principles of Quantum Logic Synthesis and its applications to Inductive Machine Learning. Based on algorithmic approach, I first design a Genetic Algorithm for Quantum Logic Synthesis that is …
An Eigenanalysis And Synthesis Of Unitary Operators Used In Quantum Computing Algorithms, Steven Randall Hutsell
An Eigenanalysis And Synthesis Of Unitary Operators Used In Quantum Computing Algorithms, Steven Randall Hutsell
Dissertations and Theses
In this work we tackle the challenge of designing quantum unitary operators which represent solutions to optimization problems. We start with a novel method which combines an evolutionary algorithm known as an Evolution Strategy (ES) with a method to randomly generate unitary operators. With this new method, a quantum operator is represented for the first time using real-valued vectors and can be "evolved" or designed to meet certain target criteria. This criteria could be the solution to an optimization problem. With the ability to evolve quantum operators, we attempt to evolve various known single and multi-qubit quantum gates as well …
Portland State Magazine, Portland State University. Office Of University Communications
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: The largest gift in Portland State’s history is also a gift to the city; Shattuck Hall gains new life; faculty and students research incorporates social and economic considerations alongside environmental ones; and more.
Forecasting The Adoption Of Emerging Energy Technologies: Managing Climate Change And Evolving Social Values, Kelly R. Cowan, Tugrul Daim, Wayne Wakeland, Hosein Fallah, Gerald Sheble, Loren Lutzenhiser, Aaron Ingle, Robert Hammond
Forecasting The Adoption Of Emerging Energy Technologies: Managing Climate Change And Evolving Social Values, Kelly R. Cowan, Tugrul Daim, Wayne Wakeland, Hosein Fallah, Gerald Sheble, Loren Lutzenhiser, Aaron Ingle, Robert Hammond
Complex Systems Faculty Publications and Presentations
With the linkage between fossil fuel use and climate change now almost universally accepted, addressing greenhouse gas emissions (GHG) has become a subject of great social urgency and technological challenge. A variety of models exists or are under development for analyzing the role of more sustainable systems, such as renewable energy technologies, in mitigating climate change. However the direct cost of these technologies is generally higher than that of fossil fuel systems. Methods are needed to more fully account for externalities, societal impacts, and social values associated with fossil fuels versus sustainable energy systems. This paper presents a conceptual model …
State Of The River Report For Toxics, Bradley Carter
State Of The River Report For Toxics, Bradley Carter
Environmental Science and Management Professional Master's Project Reports
The United States Environmental Protection Agency (EPA) strives to prevent pollution, protect water quality and improve ecosystems in order to reduce risks to human health and the environment. As outlined in the Agency’s Strategic Plan, the Columbia River Basin was identified as a "National Priority" and designated as one of our nation’s seven "Large Aquatic Ecosystems". This designation grants legislative status equal to the Chesapeake Bay, Great Lakes, Gulf of Mexico, South Florida Ecosystem, Long Island Sound and Puget Sound. The Strategic Plan is the Agency’s road map of future work efforts, and targets specific goals that are expected to …
Curriculum Change 2009-2010, Portland State University
Curriculum Change 2009-2010, Portland State University
Bulletin & Curriculum Change Documents
No abstract provided.
Bulletin: General Catalog Issue 2009-2010, Portland State University
Bulletin: General Catalog Issue 2009-2010, Portland State University
Bulletin & Curriculum Change Documents
No abstract provided.
The Mckee Preserve Management Options At Bandon Dunes Golf Resort, Ashley Marie Edwards
The Mckee Preserve Management Options At Bandon Dunes Golf Resort, Ashley Marie Edwards
Environmental Science and Management Professional Master's Project Reports
The McKee Preserve is a new conservation area at Bandon Dunes Golf Resort, located on the southern Oregon coast. The Preserve is 250 acres in size and is made up of 13 different natural resource communities. One important resource is silvery phacelia (Phacelia argentea), which is a state threatened plant species and is a species of concern federally. The goal of this project was to perform plant inventories for silvery phacelia and kinnikinnick that will be used to establish a functional management plan for the Preserve. Other resources of interest to the Preserve have been included in the …
Effect Of The Regiochemistry Of Butyl Amide Substituents On The Solution-State Structures Of Lanthanide(Iii) Dota-Tetraamide Complexes, Tomoyasu Mani, Gyula Tircsó, Piyu Zhao, A. Dean Sherry, Mark Woods
Effect Of The Regiochemistry Of Butyl Amide Substituents On The Solution-State Structures Of Lanthanide(Iii) Dota-Tetraamide Complexes, Tomoyasu Mani, Gyula Tircsó, Piyu Zhao, A. Dean Sherry, Mark Woods
Chemistry Faculty Publications and Presentations
The coordination geometry adopted by the lanthanide complexes of DOTA-tetraamides is a critical factor in determining their water exchange kinetics. Controlling the water exchange kinetics of DOTA-tetraamide complexes, and by extension their coordination geometry, is of particular interest because of the potential application of this class of complex as PARACEST MRI contrast agents. To facilitate the maximum CEST effect at the lowest pre-saturation powers much slower exchange kinetics are required than are commonly observed with these types of chelates. Complexes that adopt the more slowly exchanging square antiprismatic coordination geometry are therefore preferred; however, the factors that govern which coordination …
Exploring The Ph Dependence Of Viologen Reduction By Alpha-Carbon Radicals Derived From Hcy And Cys, Dong Wang, William E. Crowe, Robert M. Strongin, Martha Sibrian-Vazquez
Exploring The Ph Dependence Of Viologen Reduction By Alpha-Carbon Radicals Derived From Hcy And Cys, Dong Wang, William E. Crowe, Robert M. Strongin, Martha Sibrian-Vazquez
Chemistry Faculty Publications and Presentations
The colorimetric reaction of homocysteine (HCy) with a series of viologen salts suggests a linear correlation between the mid-point reduction potential of Hcy-derived α-carbon radicals and pH.
Optimising The Synthesis And Red–Green–Blue Emission Of A Simple Organic Dye, Martha Sibrian-Vazquez, Robert M. Strongin
Optimising The Synthesis And Red–Green–Blue Emission Of A Simple Organic Dye, Martha Sibrian-Vazquez, Robert M. Strongin
Chemistry Faculty Publications and Presentations
Synthetic dyes have been widely used in supramolecular chemistry not only to probe fundamental chemical interactions but also as components of functional materials. Most current efforts in this regard are directed at designing new host systems for the dyes. Herein we report on the study of a versatile new organic fluorophore. We describe a synthesis which affords improved yields in a convenient one pot procedure. Moreover, a simple method for predicting and controlling the dye’s responses to external stimuli affords a potentially practical method for achieving red–green–blue and concomitant white light generation.
A New Elasticity Element Made For Enforcing Weak Stress Symmetry, Bernardo Cockburn, Jay Gopalakrishnan, Johnny Guzmán
A New Elasticity Element Made For Enforcing Weak Stress Symmetry, Bernardo Cockburn, Jay Gopalakrishnan, Johnny Guzmán
Mathematics and Statistics Faculty Publications and Presentations
We introduce a new mixed method for linear elasticity. The novelty is a simplicial element for the approximate stress. For every positive integer k, the row-wise divergence of the element space spans the set of polynomials of total degree k. The degrees of freedom are suited to achieve continuity of the normal stresses. What makes the element distinctive is that its dimension is the smallest required for enforcing a weak symmetry condition on the approximate stress. This is achieved using certain "bubble matrices", which are special divergence-free matrix-valued polynomials. We prove that the approximation error is of order k + …
The Derivation Of Hybridizable Discontinuous Galerkin Methods For Stokes Flow, Bernardo Cockburn, Jay Gopalakrishnan
The Derivation Of Hybridizable Discontinuous Galerkin Methods For Stokes Flow, Bernardo Cockburn, Jay Gopalakrishnan
Mathematics and Statistics Faculty Publications and Presentations
In this paper, we introduce a new class of discontinuous Galerkin methods for the Stokes equations. The main feature of these methods is that they can be implemented in an efficient way through a hybridization procedure which reduces the globally coupled unknowns to certain approximations on the element boundaries. We present four ways of hybridizing the methods, which differ by the choice of the globally coupled unknowns. Classical methods for the Stokes equations can be thought of as limiting cases of these new methods.
A Single Particle Impact Model For Motion In Avalanches, J. J. P. Veerman, Dacian Daescu, M. J. Romero-Vallés, P. J. Torres
A Single Particle Impact Model For Motion In Avalanches, J. J. P. Veerman, Dacian Daescu, M. J. Romero-Vallés, P. J. Torres
Mathematics and Statistics Faculty Publications and Presentations
We describe the global behavior of the dynamics of a particle bouncing down an inclined staircase. For small inclinations all orbits eventually stop (independent of the initial condition). For large enough inclinations all orbits end up accelerating indefinitely (also independent of the initial conditions). There is an interval of inclinations of positive length between these two. In that interval the behavior of an orbit depends on its initial condition. In addition to stopping and accelerating orbits, there are also orbits with speeds bounded away from both zero and infinity. A second hallmark of the dynamics is that the orbits going …
Precession Electron Diffraction And Its Advantages For Structural Fingerprinting In The Transmission Electron Microscope, Peter Moeck, Sergei Rouvimov
Precession Electron Diffraction And Its Advantages For Structural Fingerprinting In The Transmission Electron Microscope, Peter Moeck, Sergei Rouvimov
Physics Faculty Publications and Presentations
The foundations of precession electron diffraction in a transmission electron microscope are outlined. A brief illustration of the fact that laboratory-based powder X-ray diffraction fingerprinting is not feasible for nanocrystals is given. A procedure for structural fingerprinting of nanocrystals on the basis of structural data that can be extracted from precession electron diffraction spot patterns is proposed.
A Sequential Bayesian Approach For Hydrologic Model Selection And Prediction, Kuo-Lin Hsu, Hamid Moradkhani, Soroosh Sorooshian
A Sequential Bayesian Approach For Hydrologic Model Selection And Prediction, Kuo-Lin Hsu, Hamid Moradkhani, Soroosh Sorooshian
Civil and Environmental Engineering Faculty Publications and Presentations
When a single model is used for hydrologic prediction, it must be capable of estimating system behavior accurately at all times. Multiple-model approaches integrate several model behaviors and, when effective, they can provide better estimates than that of any single model alone. This paper discusses a sequential model fusion strategy that uses the Bayes rule. This approach calculates each model's transient posterior distribution at each time when a new observation is available and merges all model estimates on the basis of each model's posterior probability. This paper demonstrates the feasibility of this approach through case studies that fuse three hydrologic …
Feedback Between Residual Circulations And Sediment Distribution In Highly Turbid Estuaries: An Analytical Model, Stefan A. Talke, Huib E. De Swart, H. M. Schuttelaars
Feedback Between Residual Circulations And Sediment Distribution In Highly Turbid Estuaries: An Analytical Model, Stefan A. Talke, Huib E. De Swart, H. M. Schuttelaars
Civil and Environmental Engineering Faculty Publications and Presentations
Motivated by field studies of the Ems estuary which show longitudinal gradients in bottom sediment concentration as high as O(0.01 kg/m4), we develop an analytical model for estuarine residual circulation based on currents from salinity gradients, turbidity gradients, and freshwater discharge. Salinity is assumed to be vertically well mixed, while the vertical concentration profile is assumed to result from a balance between a constant settling velocity and turbulent diffusive flux. Width and depth of the model estuary are held constant. Model results show that turbidity gradients enhance tidally averaged circulation upstream of the estuarine turbidity maximum (ETM), …
The Potential Contribution Of Organic Salts To New Particle Growth, Kelley Barsanti, Peter H. Mcmurry, J. N. Smith
The Potential Contribution Of Organic Salts To New Particle Growth, Kelley Barsanti, Peter H. Mcmurry, J. N. Smith
Civil and Environmental Engineering Faculty Publications and Presentations
Field and lab measurements suggest that low-molecular weight (MW) organic acids and bases exist in accumulation and nucleation mode particles, despite their relatively high pure-liquid vapor pressures. The mechanism(s) by which such compounds contribute to the mass growth of existing aerosol particles and newly formed particles has not been thoroughly explored. One mechanism by which low- MW compounds may contribute to new particle growth is through the formation of organic salts. In this paper we use thermodynamic modeling to explore the potential for organic salt formation by atmospherically relevant organic acids and bases for two system types: one in which …