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Articles 1 - 30 of 2438

Full-Text Articles in Physical Sciences and Mathematics

Farmer Attitudes Toward Cooperative Approaches To Herbicide Resistance Management: A Common Pool Ecosystem Service Challenge, David E. Ervin, Elise H. Breshears, George B. Frisvold, Terrance M. Hurley, Katherine E. Dentzman, Jeffrey L. Gunsolus, Raymond A. Jussaume, Micheal D. K. Owen, Jason Norsworthy, Mustofa Mahmud Al Mamun, Wesley Everman Mar 2019

Farmer Attitudes Toward Cooperative Approaches To Herbicide Resistance Management: A Common Pool Ecosystem Service Challenge, David E. Ervin, Elise H. Breshears, George B. Frisvold, Terrance M. Hurley, Katherine E. Dentzman, Jeffrey L. Gunsolus, Raymond A. Jussaume, Micheal D. K. Owen, Jason Norsworthy, Mustofa Mahmud Al Mamun, Wesley Everman

Environmental Science and Management Faculty Publications and Presentations

Dramatic growth in herbicide-resistant (HR) weeds in the United States threatens farm profitability and may undercut environmentally beneficial farming practices. When HR weeds move across farm boundaries due to ecological processes or human action, a common pool resource challenge emerges, requiring farmer cooperation to manage such weeds effectively. We investigate the scope for cooperative management using responses to a national survey on HR weed issues to test a recursive model of three preconditions for collective action: (1) concern about HR weeds migrating from nearby lands; (2) communication with neighbors about HR weeds; and (3) belief that cooperation is necessary for ...


Spectral Clustering For Electrical Phase Identification Using Advanced Metering Infrastructure Voltage Time Series, Logan Blakely Jan 2019

Spectral Clustering For Electrical Phase Identification Using Advanced Metering Infrastructure Voltage Time Series, Logan Blakely

Dissertations and Theses

The increasing demand for and prevalence of distributed energy resources (DER) such as solar power, electric vehicles, and energy storage, present a unique set of challenges for integration into a legacy power grid, and accurate models of the low-voltage distribution systems are critical for accurate simulations of DER. Accurate labeling of the phase connections for each customer in a utility model is one area of grid topology that is known to have errors and has implications for the safety, efficiency, and hosting capacity of a distribution system. This research presents a methodology for the phase identification of customers solely using ...


Characterizing Temperature Variability States Across Southern South America And Associated Synoptic-Scale Meteorological Patterns, Judah Adam Detzer Dec 2018

Characterizing Temperature Variability States Across Southern South America And Associated Synoptic-Scale Meteorological Patterns, Judah Adam Detzer

Dissertations and Theses

The aim of this thesis is to understand spatiotemporal temperature variability in southern South America by identifying overarching temperature variability states and their associated synoptic-scale meteorological patterns. Further, the temporal frequency of occurrence of those temperature variability states is investigated as is the role of recurrent low-frequency modes of climate variability (El Niño Southern Oscillation and the Southern Annular Mode) on temperature variability. K-means cluster analysis is used to group all months during the period 1980-2015 into four primary categories for summer and winter separately. Monthly maps of temperature anomalies are provided as input to the k-means algorithm and the ...


Samu: Design And Implementation Of Frequency Selectivity-Aware Multi-User Mimo For Wlans, Yongjiu Du, Yan Shi, Ehsan Aryafar, Pengfei Cui, Joseph Camp, Mung Chiang Dec 2018

Samu: Design And Implementation Of Frequency Selectivity-Aware Multi-User Mimo For Wlans, Yongjiu Du, Yan Shi, Ehsan Aryafar, Pengfei Cui, Joseph Camp, Mung Chiang

Computer Science Faculty Publications and Presentations

The traffic demand of wireless networks is expected to increase 1000-fold over the next decade. In anticipation of such increasing data demand for dense networks with a large number of stations, IEEE 802.11ax has introduced key technologies for capacity improvement including Orthogonal Frequency-Division Multiple Access (OFDMA), multi-user multi-input multi-output (MU-MIMO), and greater bandwidth. However, IEEE 802.11ax has yet to fully define a specific scheduling framework, on which the throughput improvement of networks significantly depends. Even within a 20 MHz of bandwidth, users experience heterogeneous channel orthogonality characteristics across sub-carriers, which prevents access points (APs) from achieving the ideal ...


Dynamics Of Prochlorococcus Diversity And Photoacclimation During Short-Term Shifts In Water Column Stratification At Station Aloha, Anne W. Thompson, Ger Van Den Engh, Nathan A. Ahlgren, Kathleen Kouba, Samantha Ward, Samuel T. Wilson, David M. Karl Dec 2018

Dynamics Of Prochlorococcus Diversity And Photoacclimation During Short-Term Shifts In Water Column Stratification At Station Aloha, Anne W. Thompson, Ger Van Den Engh, Nathan A. Ahlgren, Kathleen Kouba, Samantha Ward, Samuel T. Wilson, David M. Karl

Biology Faculty Publications and Presentations

The cyanobacterium Prochlorococcus is the dominant phototroph in surface waters of the vast oligotrophic oceans, the foundation of marine food webs, and an important component of global biogeochemical cycles. The prominence of Prochlorococcus across the environmental gradients of the open ocean is attributed to its extensive genetic diversity and flexible chlorophyll physiology, enabling light capture over a wide range of intensities. What remains unknown is the balance between temporal dynamics of genetic diversity and chlorophyll physiology in the ability of Prochlorococcus to respond to a variety of short (approximately 1 day) and longer (months to year) changes in the environment ...


High-Performance Self-Powered Uv Detector Based On Sno2-Tio2 Nanomace Arrays, Duo Chen, Lin Wei, Lingpan Meng, Yanxue Chen, Yufeng Tian, Shishen Yan, Liangmo Mei, Jun Jiao Dec 2018

High-Performance Self-Powered Uv Detector Based On Sno2-Tio2 Nanomace Arrays, Duo Chen, Lin Wei, Lingpan Meng, Yanxue Chen, Yufeng Tian, Shishen Yan, Liangmo Mei, Jun Jiao

Physics Faculty Publications and Presentations

Photoelectrochemical cell-typed self-powered UV detectors have attracted intensive research interest due to their low cost, simple fabrication process, and fast response. In this paper, SnO2-TiO2 nanomace arrays composed of SnO2 nanotube trunk and TiO2 nanobranches were prepared using soft chemical methods, and an environment-friendly self-powered UV photodetector using this nanostructure as the photoanode was assembled. Due to the synergistic effect of greatly accelerated electron-hole separation, enhanced surface area, and reduced charge recombination provided by SnO2-TiO2 nanomace array, the nanostructured detector displays an excellent performance over that based on bare SnO2 arrays. The impact of the growing time of TiO2 branches ...


Combining Atomic Force Microscopy And Shear-Force Acoustic Near-Field Microscopy To Characterize Confined Mesoscopic Fluids, Monte Allen Kozell, Theodore Brockman, Andres H. La Rosa Dec 2018

Combining Atomic Force Microscopy And Shear-Force Acoustic Near-Field Microscopy To Characterize Confined Mesoscopic Fluids, Monte Allen Kozell, Theodore Brockman, Andres H. La Rosa

Physics Faculty Publications and Presentations

An atomic force microscopy (AFM) cantilever is integrated into to a quartz tuning fork (QTF) to probe the viscoelastic properties of mesoscopic fluid layers confined between two solid surfaces under shear. Two procedures to fabricate the AFM/QTF probe are described herein. In the first, a nano-manipulator is used to transport a commercially available afm cantilever from its chip holder to the edge of a QTF tine. In the second, an afm cantilever is fabricated at the edge of the QTF tine itself. In both cases we exploit the capabilities of a dual-beam system (focused ion beam/scanning electron microscope ...


Confined Fluid Analyzed With Near-Field Acoustic Detection, Rodolfo Fernandez Rodriguez, Theodore Brockman, J. Bai, Andres H. La Rosa Dec 2018

Confined Fluid Analyzed With Near-Field Acoustic Detection, Rodolfo Fernandez Rodriguez, Theodore Brockman, J. Bai, Andres H. La Rosa

Physics Faculty Publications and Presentations

Measurement of the damping and elastic interactions between two solids interfaces (one being the apex of a tapered probe that is attached to one tine of a quartz tuning fork while the other is a flat substrate) under relative lateral oscillatory motion are reported. The solid boundaries are separated by a nanometer sized gap, and emphasis is placed on the role played by the mesoscopic fluid trapped in between. The measurements were implemented using two new acoustic techniques that have been integrated into a tuning fork based scanning probe microscope; the whole metrology system offers sub-nanometer precision for controlling the ...


Finite Element Method Analysis Of Whispering Gallery Acoustic Sensing, T. Le, H. Tran, Rodolfo Fernandez Rodriguez, C.J. Solano Salinas, Nima Laal, R. Bringas, J. Quispe, F. Segundo, Andres H. La Rosa Dec 2018

Finite Element Method Analysis Of Whispering Gallery Acoustic Sensing, T. Le, H. Tran, Rodolfo Fernandez Rodriguez, C.J. Solano Salinas, Nima Laal, R. Bringas, J. Quispe, F. Segundo, Andres H. La Rosa

Physics Faculty Publications and Presentations

Whispering Gallery Acoustic Sensing (WGAS) has recently been introduced as a sensing feedback mechanism to control the probe-sample separation distance in scanning probe microscopy that uses a quartz tuning fork as a sensor (QTF-SPM). WGAS exploits the SPM supporting frame as a resonant acoustic cavity to monitor the nanometer-sized amplitude of the QTF oscillations. Optimal WGAS sensitivity depends on attaining an exact match between the cavity's frequency peak response and the TF resonance frequency. However, two aspects play against this objective: i) the unpredictable variability of the TF resonance frequency (upon attaching a SPM-probe to one of its tines ...


Instrumentation-Level Improvements In Shear-Force Near-Field Acoustic Microscopy, J. Bai, P. Devulapalli, Theodore Brockman, Andres H. La Rosa Dec 2018

Instrumentation-Level Improvements In Shear-Force Near-Field Acoustic Microscopy, J. Bai, P. Devulapalli, Theodore Brockman, Andres H. La Rosa

Physics Faculty Publications and Presentations

The recently introduced Shear-force Near-field Acoustic Microscopy (SANM) brings a new sensing mechanism to the scanning probe microscopy family. SANM's ability to simultaneously monitor, in real time, several physical sample's responses presents some challenges for ensuring optimal operation; namely, avoid "cross-talk" among the multiple signals, address the compensation of thermal drift to ensure reproducibility of the measurements, and measuring the typical low-level signals obtained from nanometer-sized tested regions. Here, several improvements relevant to SANM, but valid for SPM in general, are addressed. i) The probe's coarse approach is performed via stepper motors, which are controlled either by ...


Probe Damage Evaluation In Frequency-Modulation Shear-Force Acoustic Near-Field Microscopy, Theodore Brockman, Rodolfo Fernandez Rodriguez, J. Bai, Monte Allen Kozell, Andres H. La Rosa Dec 2018

Probe Damage Evaluation In Frequency-Modulation Shear-Force Acoustic Near-Field Microscopy, Theodore Brockman, Rodolfo Fernandez Rodriguez, J. Bai, Monte Allen Kozell, Andres H. La Rosa

Physics Faculty Publications and Presentations

Shear-force acoustic near-field microscopy (SANM) and Whispering Gallery Acoustic Sensing have recently been introduced as a tandem system to characterize the viscoelastic response of fluids confined between two solid-boundaries in relative oscillatory lateral motion. SANM uses a) a laterally oscillating tapered probe (attached to a quartz tuning fork QTF) as one of the trapping boundaries, and b) an acoustic sensor (attached to the other flat-substrate boundary) that independently monitors the fluid’s acoustic emission. On the other and, WGAS is another technique that uses an acoustic transducer (attached to the frame holding the probe) to monitor the probe’s lateral ...


Aliased Tidal Variability In Mesoscale Sea Level Anomaly Maps, Edward Zaron, Richard D. Ray Dec 2018

Aliased Tidal Variability In Mesoscale Sea Level Anomaly Maps, Edward Zaron, Richard D. Ray

Civil and Environmental Engineering Faculty Publications and Presentations

Sea level anomaly (SLA) maps are routinely produced by objective analysis of data from the constellation of satellite altimeter missions in operation since 1992. Beginning in 2014, changes in the Data Unification and Altimeter Combination System (DUACS) used to create the SLA maps resulted in improved spatial resolution of mesoscale variability, but it also increased the levels of aliased tidal variability compared to the methodology employed prior to 2014. The present work investigates the magnitude and spatial distribution of these tidal signals, which are typically smaller than 1 cmin the open ocean but can reach tens of centimeters in the ...


Enhancing Value-Based Healthcare With Reconstructability Analysis: Predicting Cost Of Care In Total Hip Replacement, Cecily Corrine Froemke, Martin Zwick Nov 2018

Enhancing Value-Based Healthcare With Reconstructability Analysis: Predicting Cost Of Care In Total Hip Replacement, Cecily Corrine Froemke, Martin Zwick

Systems Science Faculty Publications and Presentations

Legislative reforms aimed at slowing growth of US healthcare costs are focused on achieving greater value per dollar. To increase value healthcare providers must not only provide high quality care, but deliver this care at a sustainable cost. Predicting risks that may lead to poor outcomes and higher costs enable providers to augment decision making for optimizing patient care and inform the risk stratification necessary in emerging reimbursement models. Healthcare delivery systems are looking at their high volume service lines and identifying variation in cost and outcomes in order to determine the patient factors that are driving this variation and ...


Predicting Time To Dementia Using A Quantitative Template Of Disease Progression, Murat Bilgel, Bruno Jedynak Nov 2018

Predicting Time To Dementia Using A Quantitative Template Of Disease Progression, Murat Bilgel, Bruno Jedynak

Portland Institute for Computational Science Publications

Introduction: Characterization of longitudinal trajectories of biomarkers implicated in sporadic Alzheimer's disease (AD) in decades prior to clinical diagnosis is important for disease prevention and monitoring.

Methods: We used a multivariate Bayesian model to temporally align 1369 AD Neuroimaging Initiative participants based on the similarity of their longitudinal biomarker measures and estimated a quantitative template of the temporal evolution cerebrospinal fluid (CSF) Aβ1-42, p-tau181p, and t-tau, hippocampal volume, brain glucose metabolism, and cognitive measurements. We computed biomarker trajectories as a function of time to AD dementia, and predicted AD dementia onset age in a disjoint sample.

Results ...


The Dpg-Star Method, Leszek Demkowicz, Jay Gopalakrishnan, Brendan Keith Nov 2018

The Dpg-Star Method, Leszek Demkowicz, Jay Gopalakrishnan, Brendan Keith

Portland Institute for Computational Science Publications

This article introduces the DPG-star (from now on, denoted DPG*) finite element method. It is a method that is in some sense dual to the discontinuous Petrov– Galerkin (DPG) method. The DPG methodology can be viewed as a means to solve an overdetermined discretization of a boundary value problem. In the same vein, the DPG* methodology is a means to solve an underdetermined discretization. These two viewpoints are developed by embedding the same operator equation into two different saddle-point problems. The analyses of the two problems have many common elements. Comparison to othermethods in the literature round out the newly ...


Ecosystem Services And U.S. Stormwater Planning: An Approach For Improving Urban Stormwater Decisions, Todd K. Bendor, Vivek Shandas, Brian Miles, Kenneth Belt, Lydia Olander Oct 2018

Ecosystem Services And U.S. Stormwater Planning: An Approach For Improving Urban Stormwater Decisions, Todd K. Bendor, Vivek Shandas, Brian Miles, Kenneth Belt, Lydia Olander

Urban Studies and Planning Faculty Publications and Presentations

Green stormwater infrastructure (GI) is gaining traction as a viable complement to traditional “gray” infrastructure in cities across the United States. As cities struggle with decisions to replace deteriorating stormwater infrastructure in the face of looming issues such as population growth and climate change, GI may offer a costeffective, efficient, and sustainable approach. However, decision makers confront challenges when integrating GI within city plans, including uncertainties around GI capacity and maintenance, resistance to collaboration across city governance, increasingly inflexible financing, accounting practices that do not incorporate the multiple values of GI, and difficulties in incorporating ecological infrastructure into stormwater management ...


Archetypes Of Community Wildfire Exposure From National Forests Of The Western Us, Cody Evers, Alan A. Ager, Max Nielsen-Pincus, Palaiologos Palaiologou, Ken Bunzel Oct 2018

Archetypes Of Community Wildfire Exposure From National Forests Of The Western Us, Cody Evers, Alan A. Ager, Max Nielsen-Pincus, Palaiologos Palaiologou, Ken Bunzel

Environmental Science and Management Faculty Publications and Presentations

Risk management typologies and their resulting archetypes can structure the many social and biophysical drivers of community wildfire risk into a set number of strategies to build community resilience. Existing typologies omit key factors that determine the scale and mechanism by which exposure from large wildfires occur. These factors are particularly important for land managing agencies like the US Forest Service, which must weigh community wildfire exposure against other management priorities. We analyze community wildfire exposure from national forests by associating conditions that affect exposure in the areas where wildfires ignite to conditions where exposure likely occurs. Linking source and ...


Patterns And Drivers Of Recent Disturbances Across The Temperate Forest Biome, Andreas Sommerfeld, Cornelius Senf, Brian Buma, Anthony W. D'Amato, Tiphaine Despres, Ignacio Díaz-Hormazábal, Shawn Fraver, Lee E. Frelich, Alvaro G. Gutiérrez, Sarah J. Hart, Brian J. Harvey, Hong S. He, Tomáš Hlásny, Andrés Holz, + Oct 2018

Patterns And Drivers Of Recent Disturbances Across The Temperate Forest Biome, Andreas Sommerfeld, Cornelius Senf, Brian Buma, Anthony W. D'Amato, Tiphaine Despres, Ignacio Díaz-Hormazábal, Shawn Fraver, Lee E. Frelich, Alvaro G. Gutiérrez, Sarah J. Hart, Brian J. Harvey, Hong S. He, Tomáš Hlásny, Andrés Holz, +

Geography Faculty Publications and Presentations

Increasing evidence indicates that forest disturbances are changing in response to global change, yet local variability in disturbance remains high. We quantified this considerable variability and analyzed whether recent disturbance episodes around the globe were consistently driven by climate, and if human influence modulates patterns of forest disturbance. We combined remote sensing data on recent (2001–2014) disturbances with in-depth local information for 50 protected landscapes and their surroundings across the temperate biome. Disturbance patterns are highly variable, and shaped by variation in disturbance agents and traits of prevailing tree species. However, high disturbance activity is consistently linked to warmer ...


A Spacetime Dpg Method For The Wave Equation In Multiple Dimensions, Jay Gopalakrishnan, Paulina Sepúlveda Oct 2018

A Spacetime Dpg Method For The Wave Equation In Multiple Dimensions, Jay Gopalakrishnan, Paulina Sepúlveda

Portland Institute for Computational Science Publications

A spacetime discontinuous Petrov-Galerkin (DPG) method for the linear wave equation is presented. This method is based on a weak formulation that uses a broken graph space. The wellposedness of this formulation is established using a previously presented abstract framework. One of the main tasks in the verification of the conditions of this framework is proving a density result. This is done in detail for a simple domain in arbitrary dimensions. The DPG method based on the weak formulation is then studied theoretically and numerically. Error estimates and numerical results are presented for triangular, rectangular, tetrahedral, and hexahedral meshes of ...


Ecology And Population Dynamics Of Salmonids In The Columbia River: Response Of Fishes To Anthropogenic Change In A Large Riverscape, Timothy Sean Elder Sep 2018

Ecology And Population Dynamics Of Salmonids In The Columbia River: Response Of Fishes To Anthropogenic Change In A Large Riverscape, Timothy Sean Elder

Dissertations and Theses

Freshwater ecosystems and the species that reside therein are disproportionately imperiled compared to terrestrial systems. Over the past 150 years, the Columbia River basin in the western United States has gone from one of the most productive and abundant salmon watersheds in the world, to having just a small fraction of its former salmon abundance. The cause of declines in salmon productivity and abundance are related to overlapping and confounding stressors including changes in large-scale climatic patterns and anthropogenic alterations within and adjacent to the Columbia River. Four main anthropogenic stressors have been identified as the leading causes of salmonid ...


Ideals, Big Varieties, And Dynamic Networks, Ian H. Dinwoodie Sep 2018

Ideals, Big Varieties, And Dynamic Networks, Ian H. Dinwoodie

Mathematics and Statistics Faculty Publications and Presentations

The advantage of using algebraic geometry over enumeration for describing sets related to attractors in large dynamic networks from biology is advocated. Examples illustrate the gains.


Gps Constraints On Deformation In Northern Central America From 1999 To 2017, Part 1 – Time-Dependent Modelling Of Large Regional Earthquakes And Their Post-Seismic Effects, A. Ellis, Charles Demets, P. Briole, Beatriz Cosenza, Omar Flores, Shannon Graham, Marco Guzmán-Speziale, Douglas Hernandez, Vladimir Kostoglodov, Peter Lafemina, Neal Lord, Cécile Lasserre, Hélène Lyon-Caen, Manuel Rodriguez Maradiaga, Robert Mccaffrey, Enrique Molina, Jeffrey Rivera, Robert Rogers, Alejandra Staller Sep 2018

Gps Constraints On Deformation In Northern Central America From 1999 To 2017, Part 1 – Time-Dependent Modelling Of Large Regional Earthquakes And Their Post-Seismic Effects, A. Ellis, Charles Demets, P. Briole, Beatriz Cosenza, Omar Flores, Shannon Graham, Marco Guzmán-Speziale, Douglas Hernandez, Vladimir Kostoglodov, Peter Lafemina, Neal Lord, Cécile Lasserre, Hélène Lyon-Caen, Manuel Rodriguez Maradiaga, Robert Mccaffrey, Enrique Molina, Jeffrey Rivera, Robert Rogers, Alejandra Staller

Geology Faculty Publications and Presentations

We use continuous and campaign measurements from 215 GPS sites in northern Central America and southern Mexico to estimate coseismic and afterslip solutions for the 2009 Mw = 7.3 Swan Islands fault strike-slip earthquake and the 2012 Mw = 7.3 El Salvador and Mw = 7.4 Guatemala thrust-faulting earthquakes on the Middle America trench. Our simultaneous, time-dependent inversion of more than 350 000 daily GPS site positions gives the first jointly consistent estimates of the coseismic slips for all three earthquakes, their combined time-dependent post-seismic effects and secular station velocities corrected for both the coseismic and post-seismic deformation. Our geodetic ...


Decadal Topographic Change In The Mcmurdo Dry Valleys Of Antarctica: Thermokarst Subsidence, Glacier Thinning, And Transfer Of Water Storage From The Cryosphere To The Hydrosphere, J. S. Levy, Andrew G. Fountain, M. K. Obryk, J. Telling, Craig Glennie, M. Gooseff, David J. Van Horn Sep 2018

Decadal Topographic Change In The Mcmurdo Dry Valleys Of Antarctica: Thermokarst Subsidence, Glacier Thinning, And Transfer Of Water Storage From The Cryosphere To The Hydrosphere, J. S. Levy, Andrew G. Fountain, M. K. Obryk, J. Telling, Craig Glennie, M. Gooseff, David J. Van Horn

Geology Faculty Publications and Presentations

Recent local-scale observations of glaciers, streams, and soil surfaces in the McMurdo Dry Valleys of Antarctica (MDV) have documented evidence for rapid ice loss, glacial thinning, and ground surface subsidence associated with melting of ground ice. To evaluate the extent,magnitude, and location of decadal-scale landscape change in the MDV, we collected airborne lidar elevation data in 2014–2015 and compared these data to a 2001–2002 airborne lidar campaign. This regional assessment of elevation change spans the recent acceleration of warming and melting observed by long-term meteorological and ecosystem response experiments, allowing us to assess the response of MDV ...


Using Strong Laser Fields To Produce Antihydrogen Ions, Christopher M. Keating Aug 2018

Using Strong Laser Fields To Produce Antihydrogen Ions, Christopher M. Keating

Dissertations and Theses

We provide estimates of both cross section and rate for the stimulated attachment of a second positron into the (1s2 1Se) state of the H+ ion using Ohmura and Ohmura's (1960 Phys. Rev. 118 154) effective range theory, Reiss's strong field approximation (1980 Phys. Rev. A 22, 1786), and the principle of detailed balancing. Our motivation for producing H+ ion include its potential to be used as an intermediate state in bringing antihydrogen to ultra-cold (sub-mK) temperatures required for a variety of studies, which include both spectroscopy and the probing of the gravitational interaction of ...


Supercanonical Probability Distributions, John D. Ramshaw Aug 2018

Supercanonical Probability Distributions, John D. Ramshaw

Physics Faculty Publications and Presentations

The canonical probability distribution describes a system in thermal equilibrium with an infinite heat bath. When the bath is finite the distribution is modified. These modifications can be derived by truncating a Taylor-series expansion of the entropy of the heat bath, but their form depends on the expansion parameter chosen. We consider two such expansions, which yield supercanonical (i.e., higher-order canonical) distributions of exponential and power-law form. The latter is identical in form to the "Tsallis distribution," which is therefore a valid asymptotic approximation for an arbitrary finite heat bath, but bears no intrinsic relation to Tsallis entropy.


Twelve Questions For The Participatory Modeling Community, Rebecca Jordan, Steven Gray, Moira Zellner, Pierre D. Glynn, Alexey Voinov, Beatrice Hedelin, Eleanor J. Sterling, Kirsten Leong, Laura Schmitt Olabisi, Klaus Hubacek, Pierre Bommel, Todd K. Bendor, Antoine J. Jetter, Bethany Laursen, Alison Singer, Philippe J. Giabbanelli, Nagesh Kolagani, Laura Basco Carrera, Karen Jenni, Christina Prell, National Socio-Environmental Synthesis Center Participatory Modeling Pursuit Working Group Aug 2018

Twelve Questions For The Participatory Modeling Community, Rebecca Jordan, Steven Gray, Moira Zellner, Pierre D. Glynn, Alexey Voinov, Beatrice Hedelin, Eleanor J. Sterling, Kirsten Leong, Laura Schmitt Olabisi, Klaus Hubacek, Pierre Bommel, Todd K. Bendor, Antoine J. Jetter, Bethany Laursen, Alison Singer, Philippe J. Giabbanelli, Nagesh Kolagani, Laura Basco Carrera, Karen Jenni, Christina Prell, National Socio-Environmental Synthesis Center Participatory Modeling Pursuit Working Group

Engineering and Technology Management Faculty Publications and Presentations

Participatory modeling engages the implicit and explicit knowledge of stakeholders to create formalized and shared representations of reality and has evolved into a field of study as well as a practice. Participatory modeling researchers and practitioners who focus specifically on environmental resources met at the National Socio-Environmental Synthesis Center (SESYNC) in Annapolis, Maryland, over the course of 2 years to discuss the state of the field and future directions for participatory modeling. What follows is a description of 12 overarching groups of questions that could guide future inquiry.


Using Wetlands To Prevent The Surface Accumulation Of Aphanizomenon Flos-Aquae From Upper Klamath Lake, Arick Christopher Rouhe Aug 2018

Using Wetlands To Prevent The Surface Accumulation Of Aphanizomenon Flos-Aquae From Upper Klamath Lake, Arick Christopher Rouhe

Dissertations and Theses

The ability to regulate buoyancy (sinking and floating) using cellular gas vesicles is a unique characteristic that allows many common bloom-forming cyanobacteria to accumulate at water surfaces and dominate systems. Typical control and management strategies include nutrient manipulation and phosphorus reduction, which are effective but do not reduce the advantage of buoyancy control. Since buoyancy control is based upon a mechanism that is driven by photosynthesis along with environmental conditions that trigger vesicle formation and ion exchange, buoyancy regulation can be influenced by manipulating extracellular conditions. In this study I manipulated extracellular conditions using wetland water and additions of potassium ...


Waste Stream And Green Purchasing Analysis At Bonneville Lock And Dam, Alexander Bienko Aug 2018

Waste Stream And Green Purchasing Analysis At Bonneville Lock And Dam, Alexander Bienko

Master of Environmental Management Project Reports

The United States Army Corps of Engineers (USACE), Portland District, has jurisdiction on three locks and four dams in the Columbia River basin. These sites “contribute to a water resource management system that provides flood risk management, power generation, water quality improvement, fish and wildlife habitat and recreation on the Columbia River and some of its tributaries”. The Bonneville Lock and Dam (Bonneville Project) site lies on the Columbia River approximately 40 miles east from Portland, Oregon. Portions of the site have been declared a National Historic Landmark, from its origins in President Franklin D. Roosevelt’s New Deal program ...


Tools And Methods In Participatory Modeling: Selecting The Right Tool For The Job, Alexey Voinov, Karen Jenni, Steven Gray, Nagesh Kolagani, Pierre D. Glynn, Pierre Bommel, Christina Prell, Moira Zellner, Michael Paolisso, Rebecca Jordan, Eleanor J. Sterling, Laura Schmitt Olabisi, Philippe J. Giabbanelli, Zhanli Sun, Christophe Le Page, Sondoss Elsawah, Todd K. Bendor, Klaus Hubacek, Bethany Laursen, Antoine J. Jetter, Laura Basco-Carrera, Alison Singer, Laura Young, Jessica Brunacini, Alex Smajgl Aug 2018

Tools And Methods In Participatory Modeling: Selecting The Right Tool For The Job, Alexey Voinov, Karen Jenni, Steven Gray, Nagesh Kolagani, Pierre D. Glynn, Pierre Bommel, Christina Prell, Moira Zellner, Michael Paolisso, Rebecca Jordan, Eleanor J. Sterling, Laura Schmitt Olabisi, Philippe J. Giabbanelli, Zhanli Sun, Christophe Le Page, Sondoss Elsawah, Todd K. Bendor, Klaus Hubacek, Bethany Laursen, Antoine J. Jetter, Laura Basco-Carrera, Alison Singer, Laura Young, Jessica Brunacini, Alex Smajgl

Engineering and Technology Management Faculty Publications and Presentations

Various tools and methods are used in participatory modelling, at different stages of the process and for different purposes. The diversity of tools and methods can create challenges for stakeholders and modelers when selecting the ones most appropriate for their projects. We offer a systematic overview, assessment, and categorization of methods to assist modelers and stakeholders with their choices and decisions. Most available literature provides little justification or information on the reasons for the use of particular methods or tools in a given study. In most of the cases, it seems that the prior experience and skills of the modelers ...


Special Issue On Climate Change And Land Conservation And Restoration: Advances In Economics Methods And Policies For Adaptation And Mitigation, Sarah Cline, Sahan T.M. Dissanayake Aug 2018

Special Issue On Climate Change And Land Conservation And Restoration: Advances In Economics Methods And Policies For Adaptation And Mitigation, Sarah Cline, Sahan T.M. Dissanayake

Economics Faculty Publications and Presentations

Climate change will likely impact the ecosystem services and biodiversity generated from conserved land. Land conservation can also play a significant role in achieving cost-effective mitigation of greenhouse gas emissions. In this special issue we feature seven papers from the 2017 NAREA Workshop, “Climate Change and Land Conservation and Restoration: Advances in Economics Methods and Policies for Adaptation and Mitigation.” The articles include papers furthering the methodological frontier; portfolio optimization, dynamic rangeland stocking, and global timber harvest models, and those highlighting innovative applications; climate smart agricultural practices in Nigeria and Vietnam, welfare impacts on birding, and carbon and albedo pricing.