Physical Sciences and Mathematics Commons^™

Sustainable Municipal Operations: Albany, Oregon, Portland State University. Hatfield School Of Government. Center For Public Service, Ed Gallagher, Dave Rouse, Dennis Kurtz, Tanya Johnston

Center for Public Service Publications and Reports

Portland State University, Hatfield School of Government (PSU), and Northwest Energy Efficiency Alliance (NEEA), has formed a partnership to develop Sustainable Municipal Operations Plans that documents sustainability and energy management best practices. The goal of this partnership is to determine how a City/municipality can actively manage energy as a controllable expense by following a predetermined operation protocol. The PSU team developed a framework of best practices for sustainable municipal operations in different categories including facilities, fleet, purchasing, operations and the work environment. After identifying pilot jurisdictions, the team applied these best practices to the current operations of local governments in …

Sustainable County Operations: Yamhill County, Oregon, Portland State University. Hatfield School Of Government. Center For Public Service, Ed Gallagher, Dave Rouse, Dennis Kurtz, Tanya Johnston

Center for Public Service Publications and Reports

Portland State University, Hatfield School of Government (PSU), and Northwest Energy Efficiency Alliance (NEEA), has formed a partnership to develop Sustainable Municipal Operations Plans that documents sustainability and energy management best practices. The goal of this partnership is to determine how a county/municipality can actively manage energy as a controllable expense by following a predetermined operation protocol. The PSU team developed a framework of best practices for sustainable municipal operations in different categories including facilities, fleet, purchasing, operations and the work environment. After identifying pilot jurisdictions, the team applied these best practices to the current operations of local governments in …

Sustainable Municipal Operations: Independence, Oregon, Portland State University. Hatfield School Of Government. Center For Public Service, Ed Gallagher, Dave Rouse, Dennis Kurtz, Tanya Johnston

Center for Public Service Publications and Reports

Portland State University, Hatfield School of Government (PSU), and Northwest Energy Efficiency Alliance (NEEA), has formed a partnership to develop Sustainable Municipal Operations Plans that documents sustainability and energy management best practices. The goal of this partnership is to determine how a City/municipality can actively manage energy as a controllable expense by following a predetermined operation protocol. The PSU team developed a framework of best practices for sustainable municipal operations in different categories including facilities, fleet, purchasing, operations and the work environment. After identifying pilot jurisdictions, the team applied these best practices to the current operations of local governments in …

Engaging The Community Through An Undergraduate Biomedical Physics Course, Grace Van Ness, Ralf Widenhorn

Physics Faculty Publications and Presentations

We report on the development of an undergraduate biomedical physics course at Portland State University, motivated by both student interest and the desire of the university?s Physics Department to provide an interdisciplinary intermediate-level physics course. The course was developed through the community engagement of physicians, clinical researchers, and basic science researchers. Class meetings were a combination of regular and guest lectures, hands-on exercises, web-based activities, class discussions, and a student poster information session for patrons at a local science museum. The course inspired students to engage in research projects in biomedical physics that enhance their understanding of science and education …

The Influence Of Market Proximity On National Forest Hazardous Fuels Treatments, Max Nielsen-Pincus, Susan Charnley, Cassandra Moseley

Environmental Science and Management Faculty Publications and Presentations

The US Department of Agriculture Forest Service's focus on hazardous fuels reduction has increased since the adoption of the National Fire Plan in 2001. However, appropriations for hazardous fuels reduction still lag behind wildfire suppression spending. Offsetting fuels treatment costs through biomass utilization or by using innovative administrative mechanisms such as stewardship contracting are two approaches to stretching appropriated dollars further across the landscape. We use fuels treatment data (n = 8,451 locations) to ask how wood- processing infrastructure influences where and how much hazardous fuels treatments, biomass utilization, and stewardship contracting occur on national forests in Oregon and Washington. …

Long-Term Integrated Studies Show Complex And Surprising Effects Of Climate Change In The Northern Hardwood Forest, Peter M. Groffman, Lindsay E. Rustad, Pamela H. Templer, John L. Campbell, Lynn M. Christenson, Nina K. Lany, Anne M. Socci, Matthew A. Vadeboncoeur, Paul G. Schaberg, Geoffrey W. Wilson, Charles T. Driscoll, Timothy J. Fahey, Melany C. Fisk, Christine L. Goodale, Mark B. Green, Steven P. Hamburg, Chris E. Johnson, Mryon J. Mitchell, Jennifer L. Morse, Linda H. Pardo, Nicholas L. Rodenhouse

Environmental Science and Management Faculty Publications and Presentations

Evaluations of the local effects of global change are often confounded by the interactions of natural and anthropogenic factors that overshadow the effects of climate changes on ecosystems. Long-term watershed and natural elevation gradient studies at the Hubbard Brook Experimental Forest and in the surrounding region show surprising results demonstrating the effects of climate change on hydrologic variables (e.g., evapotranspiration, streamflow, soil moisture); the importance of changes in phenology on water, carbon, and nitrogen fluxes during critical seasonal transition periods; winter climate change effects on plant and animal community composition and ecosystem services; and the effects of anthropogenic disturbances and …

The Distribution And Reproductive Success Of The Western Snowy Plover Along The Oregon Coast - 2012, David J. Lauten, Kathleen J. Castelein, J. Daniel Farrar, Adam A. Kotaich, Eleanor P. Gaines

Institute for Natural Resources Publications

From 5 April – 21 September 2012 we monitored the distribution, abundance and productivity of the federally Threatened Western Snowy Plover (Charadrius nivosus nivosus) along the Oregon coast. From north to south, we surveyed and monitored plover activity at Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North Tahkenitch Creek, Tenmile Creek, Coos Bay North Spit, Bandon Snowy Plover Management Area, New River HRA and adjacent lands, and Floras Lake. Our objectives for the Oregon coastal population in 2012 were to: 1) estimate the size of the adult Snowy Plover population, 2) locate plover nests, 3) determine nest …

Effects Of Sn Doping On The Morphology And Properties Of Fe-Doped In2o3 Epitaxial Films, Tie Zhou, Lin Wei, Yanru Xie, Qinghao Li, Guoxiang Hu, Yanxue Chen, Shishen Yan, Guolei Liu, Liangmo Mei, Jun Jiao

Physics Faculty Publications and Presentations

(Sn, Fe)-codoped In₂O₃ epitaxial films were deposited on (111)-oriented Y-stabilized ZrO₂ substrates by pulsed laser deposition with constant Fe concentration and different Sn concentrations. The influence of Sn concentration on the crystal structure and properties of Fe-doped In₂O₃ ferromagnetic semiconductor films has been investigated systematically. Experimental results indicate that Sn doping can effectively reduce the surface roughness and suppresses breakup of the films into separated islands. At the same time, the optical band gap increases and the electrical properties improve correspondingly. However, although the carrier density increases dramatically with the Sn doping, no obvious change of the ferromagnetism is observed. …

Divergent Carbon Dynamics Under Climate Change In Forests With Diverse Soils, Tree Species, And Land Use Histories, Robert M. Scheller, Alec M. Kretchun, Steve Van Tuyl, Kenneth L. Clark, Melissa S. Lucash, John Hom

Environmental Science and Management Faculty Publications and Presentations

Accounting for both climate change and natural disturbances—which typically result in greenhouse gas emissions—is necessary to begin managing forest carbon sequestration. Gaining a complete understanding of forest carbon dynamics is, however, challenging in systems characterized by historic over-utilization, diverse soils and tree species, and frequent disturbance. In order to elucidate the cascading effects of potential climate change on such systems, we projected forest carbon dynamics, including soil carbon changes, and shifts in tree species composition as a consequence of wildfires and climate change in the New Jersey pine barrens (NJPB) over the next 100 years. To do so, we used …

The Ecosystem Service Value Of Coastal Wetlands For Cyclone Protection In Australia, Petina Pert, Robert Costanza, Iris Bohnet, James Butler, Ida Kubiszewski, Paul Sutton, Kenneth Mulder, E. (Erin) Bohensky

Institute for Sustainable Solutions Publications and Presentations

Slides from a presentation given at an International Conference and Workshop, June 7-10, 2010, titled Solutions for Sustaining Natural Capital and Ecosystem Services.

Crystallography Open Database (Cod): An Open-Access Collection Of Crystal Structures And Platform For World-Wide Collaboration, Saulius Gražulis, Adriana Daškevič, Andrius Merkys, Daniel Chateigner, Luca Lutterotti, Miguel Quirós, Nadezhda R. Serebryanaya, Peter Moeck, Robert T. Downs, Armel Le Bail

Physics Faculty Publications and Presentations

Using an open-access distribution model, the Crystallography Open Database (COD, http://www.crystallography.net) collects all known 'small molecule / small to medium sized unit cell' crystal structures and makes them available freely on the Internet. As of today, the COD has aggregated ~150,000 structures, offering basic search capabilities and the possibility to download the whole database, or parts thereof using a variety of standard open communication protocols. A newly developed website provides capabilities for all registered users to deposit published and so far unpublished structures as personal communications or pre-publication depositions. Such a setup enables extension of the COD database by many …

Temporal And Crustal Effects On Differentiation Of Tholeiite To Calcalkaline And Ferro-Trachytic Suites, High Lava Plains, Oregon, Usa, Martin J. Streck, Anita L. Grunder

Geology Faculty Publications and Presentations

Strongly bimodal, basalt-rhyolite volcanism of the High Lava Plains Province of Oregon followed the Middle Miocene flood basalts of the Pacific Northwest and extends to recent time. During the 8 m.y. of volcanism recorded in the central High Lava Plains, in western Harney Basin, three distinct mafic magmatic trends originate from primitive high-alumina olivine tholeiites (HAOT); they are tholeiitic, calcalkaline and ferro-trachytic. Tholeiitic basalts occur throughout the history and their compositions are derived by crystal fractionation while traversing the crust and mixing with evolved mafic magmas. Scavenging of apatite from crustal rocks and minor contamination with felsic melts accounts for …

Land Cover, Climate, And The Summer Surface Energy Balance In Phoenix, Az, And Portland, Or, Ariane Middel, Anthony J. Brazel, Patricia Gober, Soe Win Myint, Heejun Chang, Jiunn-Der Duh

Institute for Sustainable Solutions Publications and Presentations

Changes in land use and land cover alter the local energy balance and contribute to distinct urban climates. This paper presents a local-scale above-canopy study of intra-urban land cover mixes in two cities to analyse the relative effects of surface morphology and local climate on the surface energy balance (SEB). The study is conducted for urban areas in Phoenix, Arizona, and Portland, Oregon, cities with distinct climates but similarly warm and dry summers. A Local-Scale Urban Meteorological Parameterization Scheme (LUMPS) is used to analyse the relative contributions of local weather extremes and land cover variations on the urban energy balance. …

A System For Bidirectional Robotic Pathfinding, Tesca Fitzgerald

Computer Science Faculty Publications and Presentations

The accuracy of an autonomous robot's intended navigation can be impacted by environmental factors affecting the robot's movement. When sophisticated localizing sensors cannot be used, it is important for a pathfinding algorithm to provide opportunities for landmark usage during route execution, while balancing the efficiency of that path. Although current pathfinding algorithms may be applicable, they often disfavor paths that balance accuracy and efficiency needs. I propose a bidirectional pathfinding algorithm to meet the accuracy and efficiency needs of autonomous, navigating robots.

Self-Assembled Nanoparticle Antiglare Coatings, Khalid Askar, Blayne M. Phillips, Xuan Dou, Juan Lopez, Carl Smith, Bin Jiang, Peng Jiang

Mathematics and Statistics Faculty Publications and Presentations

Here we report a simple and scalable bottom-up technology for assembling close-packed nanoparticle monolayers on both sides of a glass substrate as high-quality antiglare coatings. Optical measurements show that monolayer coatings consisting of 110 nm silica nanoparticles can significantly reduce optical reflectance and enhance specular transmittance of the glass substrate for a broad range of visible wavelengths. Both experiments and numerical simulations reveal that the antiglare properties of the self-assembled colloidal monolayers are significantly affected by the size of the colloidal particles.

Progress Toward Red And Near-Infrared (Nir) Emitting Saccharide Sensors, Martha Sibrian-Vazquez, Jorge O. Escobedo, Mark Lowry, Robert M. Strongin

Chemistry Faculty Publications and Presentations

Red-shifted and near-infrared (NIR)-active rhodamine analogs and their boronic acid derivatives were synthesized and studied. These latter compounds function as fluorogenic NIR active substrates for sugar sensing. The effects of benzannulation and boronic acid functionalization on fluorophore optical and sensing properties are described.

Differential Effects Of The Hydrophobic Surfactant Proteins On The Formation Of Inverse Bicontinuous Cubic Phases, Mariya Chavarha, Ryan W. Loney, Kamlesh Kumar, Shankar B. Rananavare, Stephen B. Hall

Chemistry Faculty Publications and Presentations

Prior studies have shown that the biological mixture of the two hydrophobic surfactant proteins, SP-B and SP-C, produces faster adsorption of the surfactant lipids to an air/water interface, and that they induce 1-palmitoyl-2-oleoyl phosphatidylethanolamine (POPE) to form inverse bicontinuous cubic phases. SP-B has a much greater effect than SP-C on adsorption. If the two proteins induce formation of the bicontinuous structures and faster adsorption by similar mechanisms, then they should also have differential ability to form the cubic phases. To test this hypothesis, we measured small angle X-ray scattering on the individual proteins combined with POPE. SP-B replicated the doserelated …

Beyond Adaptive Capacity Checklists: Examining The Construction Of Capacity In Mexico City And Santiago, Patricia Romero-Lankao, Sara Hughes, Angélica Rosas-Huerta, Roxana Borquéz, Melissa Haeffner

Environmental Science and Management Faculty Publications and Presentations

Cities are vulnerable to a range of environmental hazards that are likely to be exacerbated by climate change: floods, droughts, poor air quality, and heat islands are a few examples. Assessments of this vulnerability often include an evaluation of a city’s adaptive capacity, or its potential to respond to changes in the frequency or severity of environmental hazards as well as its ability to take advantage of or mitigate these changes. For example, at the city (e.g., institutional) level, a common metric of adaptive capacity is the availability and effective use of information. In many cases, a city would receive …

Reconstructability Of Epistatic Functions, Martin Zwick, Joe Fusion, Beth Wilmot

Systems Science Faculty Publications and Presentations

Background: Reconstructability Analysis (RA) has been used to detect epistasis in genomic data; in that work, even the simplest RA models (variable-based models without loops) gave performance superior to two other methods. A follow-on theoretical study showed that RA also offers higher-resolution models, namely variable-based models with loops and state-based models, likely to be even more effective in modeling epistasis, and also described several mathematical approaches to classifying types of epistasis.

Methods: The present paper extends this second study by discussing a non-standard use of RA: the analysis of epistasis in quantitative as opposed to nominal variables; such quantitative variables …

Decay Rates Of A Molecule In The Vicinity Of A Spherical Surface Of An Isotropic Magnetodielectric Material, H. Y. Chung, P.T. Leung, D. P. Tsai

Physics Faculty Publications and Presentations

A comprehensive study is presented on the decay rates of excited molecules in the vicinity of a magnetodielectric material of spherical geometry via electrodynamic modeling. Both the models based on a driven-damped harmonic oscillator and on energy transfers will be applied so that the total decay rates can be rigorously decomposed into the radiative and the nonradiative rates. Clarifications of the equivalence of these two models for arbitrary geometry will be provided. Different possible orientations and locations of the molecule are studied with the molecule being placed near a spherical particle or a cavity. Among other results, TE modes are …

Annealing Effect On Photovoltaic Performance Of Cdse Quantum-Dots-Sensitized Tio2 Nanorod Solar Cells, Yitan Li, Lin Wei, Ruizi Zhang, Yanxue Chen, Jun Jiao

Physics Faculty Publications and Presentations

Large area rutile TiO₂ nanorod arrays were grown on F:SnO₂ (FTO) conductive glass using a hydrothermal method at low temperature. CdSe quantum dots (QDs) were deposited onto single-crystalline TiO₂ nanorod arrays by a chemical bath deposition (CBD) method to make a photoelectrode. The solar cell was assembled using a CdSe-TiO₂ nanostructure as the photoanode and polysulfide solution as the electrolyte. The annealing effect on optical and photovoltaic properties of CdSe quantum-dotssensitized TiO₂ nanorod solar cells was studied systematically. A significant change of the morphology and a regular red shift of band gap of CdSe nanoparticles were observed after annealing treatment. …

Controlled Spatial Switching And Routing Of Surface Plasmons In Designed Single-Crystalline Gold Nanostructures, Rolf Kӧnenkamp, Robert Campbell Word, Joseph Fitzgerald, Athavan Nadarajah, S. D. Saliba

Physics Faculty Publications and Presentations

Electron emission microscopy is used to visualize plasmonic routing in gold nano-structures. We show that in single-crystalline gold structures reliable routing can be achieved with polarization switching. The routing is due to the polarization dependence of the photon-to-plasmon coupling, which controls the mode distribution in the plasmonic gold film. We use specifically designed, single-crystalline planar structures. In these structures, the plasmon propagation length is sufficiently large such that significant plasmon power can be delivered to the near-field region around the end tips of the router. Solid state devices based on internal electron excitation and emission processes appear feasible.

Dark Current Modeling With A Moving Depletion Edge, Justin Charles Dunlap, Morley M. Blouke, Erik Bodegom, Ralf Widenhorn

Physics Faculty Publications and Presentations

Within a pixel in a digital imager, generally either a chargecoupled device or complementary metal oxide semiconductor device, doping of the semiconductor substrate and application of gate voltages create a region free of mobile carriers called the depletion region. This region fills with charge after incoming photons or thermal energy raise the charges from the valence to the conduction energy band. As the signal charge fills the depletion region, the electric field generating the region is altered, and the size of the region is reduced. We present a model that describes how this dynamic depletion region, along with the location …

Well Conditioned Boundary Integral Equations For Two-Dimensional Sound-Hard Scattering Problems In Domains With Corners, Akash Anand, Jeffrey S. Ovall, Catalin Turc

Mathematics and Statistics Faculty Publications and Presentations

We present several well-posed, well-conditioned direct and indirect integral equation formulations for the solution of two-dimensional acoustic scattering problems with Neumann boundary conditions in domains with corners. We focus mainly on Direct Regularized Combined Field Integral Equation (DCFIE-R) formulations whose name reflects that (1) they consist of combinations of direct boundary integral equations of the second-kind and first-kind integral equations which are preconditioned on the left by coercive boundary single-layer operators, and (2) their unknowns are physical quantities, i.e., the total field on the boundary of the scatterer. The DCFIE-R equations are shown to be uniquely solvable in appropriate function …

Measuring The Longitudinal Effects Of Food Carbon Footprint Training On Consumers: Knowledge, Attitudes, And Behavioral Intentions, Robin Wikoff, Gretchen N. Rainbolt, Wayne Wakeland

Systems Science Faculty Publications and Presentations

Although the supply chains through which foods are produced, processed, and transported can have a significant impact on carbon dioxide (CO₂) emissions, consumers are largely unaware of how their food choices may impact the environment. Based on a previous related study, we hypothesized that a web-based training process could increase consumer knowledge and perhaps influence consumer behavior longitudinally. To test this, food distribution networks were modeled and analyzed to determine CO₂ footprints for a variety of foods, and a training process was designed to teach consumers about the CO₂ emissions for different types of foods that …

Open Structure Zno/Cdse Core/Shell Nanoneedle Arrays For Solar Cells, Yanxue Chen, Lin Wei, Guanghua Zhang, Jun Jiao

Physics Faculty Publications and Presentations

Open structure ZnO/CdSe core/shell nanoneedle arrays were prepared on a conducting glass (SnO2:F) substrate by solution deposition and electrochemical techniques. A uniform CdSe shell layer with a grain size of approximately several tens of nanometers was formed on the surface of ZnO nanoneedle cores after annealing at 400°C for 1.5 h. Fabricated solar cells based on these nanostructures exhibited a high short-circuit current density of about 10.5 mA/cm2 and an overall power conversion efficiency of 1.07% with solar illumination of 100 mW/cm2. Incident photo-to-current conversion efficiencies higher than 75% were also obtained.

Turbulent Concentration Diffusion In Multiphase Flow, John D. Ramshaw

Physics Faculty Publications and Presentations

In multifluid multiphase flow models, the velocity of each phase is determined by its own momentum equation, which is coupled to the other phases by pairwise interphase drag forces proportional to velocity differences. When the drag coefficients are large, the phase velocities become nearly equal and the relative motion of the phases becomes diffusional rather than inertial. The multifluid momentum equations then reduce to a single momentum equation for the mixture and a system of linear relations that determine the small residual velocity differences between the phases. We derive such diffusional relations in a very general form that applies to …

A Mean Curvature Model For Capillary Flows In Asymmetric Containers And Conduits, Yongkang Chen, Noël Tavan, Mark M. Weislogel

Mechanical and Materials Engineering Faculty Publications and Presentations

Capillarity-driven flows resulting from critical geometric wetting criterion are observed to yield significant shifts of the bulk fluid from one side of the container to the other during "zero gravity" experiments. For wetting fluids, such bulk shift flows consist of advancing and receding menisci sometimes separated by secondary capillary flows such as rivulet-like flows along gaps. Here we study the mean curvature of an advancing meniscus in hopes of approximating a critical boundary condition for fluid dynamics solutions. It is found that the bulk shift flows behave as if the bulk menisci are either “connected” or "disconnected." For the connected …

Some Unified Results On Comparing Linear Combinations Of Independent Gamma Random Variables, Subhash C. Kochar, Maochao Xu

Mathematics and Statistics Faculty Publications and Presentations

In this paper, a new sufficient condition for comparing linear combinations of independent gamma random variables according to star ordering is given. This unifies some of the newly proved results on this problem. Equivalent characterizations between various stochastic orders are established by utilizing the new condition. The main results in this paper generalize and unify several results in the literature including those of Amiri, Khaledi, and Samaniego [2], Zhao [18], and Kochar and Xu [9].

Using Environmental Variables And Soil Processes To Forecast Denitrification Potential And Nitrous Oxide Fluxes In Coastal Plain Wetlands Across Different Land Uses, Jennifer L. Morse, Marcelo Ardón, Emily S. Bernhardt

Environmental Science and Management Faculty Publications and Presentations

We examined relationships between denitrification (DNF) and nitrous oxide (N2O) fluxes and potentially important chemical and physical predictors to build a predictive understanding of gaseous N losses from coastal plain wetlands. We collected soil, gas, and pore water samples from 48 sampling locations across a large (440 ha) restored wetland, an adjacent drained agricultural field, and nearby forested wetlands every two months over two years. In summer and fall 2007, we measured soil DNF potential (21.6-3560 mg N m-3 d-1) and N2O efflux (-4.36-8.81 mg N m -2 d-1), along with 17 predictor variables. We developed statistical models for the …