Digital Commons Network^™

Time Varying Parameter Models For Catchments With Land Use Change: The Importance Of Model Structure, Sahani Pathiraja, Daniela Anghileri, Paolo Burlando, Ashish Sharma, Lucy Marshall, Hamid Moradkhani

Civil and Environmental Engineering Faculty Publications and Presentations

Rapid population and economic growth in South-East-Asia has been accompanied by extensive land use change with consequent impacts on catchment hydrology. Modelling methodologies capable of handling changing land use conditions are therefore becoming ever more important, and are receiving increasing attention from hydrologists. A recently developed Data Assimilation based framework that allows model parameters to vary through time in response to signals of change in observations is considered for a medium sized catchment (2880 km²) in Northern Vietnam experiencing substantial but gradual land cover change. We investigate the efficacy of the method as well as the importance of the chosen …

Bending The Carbon Curve: Fire Management For Carbon Resilience Under Climate Change, E. Louise Loudermilk, Robert M. Scheller, Peter J. Weisberg, Alec M. Kretchun

Environmental Science and Management Faculty Publications and Presentations

Context: Forest landscapes are increasingly managed for fire resilience, particularly in the western US which has recently experienced drought and widespread, high-severity wildfires. Fuel reduction treatments have been effective where fires coincide with treated areas. Fuel treatments also have the potential to reduce drought-mortality if tree density is uncharacteristically high, and to increase long-term carbon storage by reducing high-severity fire probability.

Objective: Assess whether fuel treatments reduce fire intensity and spread and increase carbon storage under climate change.

Methods: We used a simulation modeling approach that couples a landscape model of forest disturbance and succession with an ecosystem model of …

Indigenous Nations Studies Newsletter, Summer 2017, Portland State University. Indigenous Nations Studies

Indigenous Nations Studies Newsletter

Table of Contents:
-- Directors Note
-- A Case for Collaboration
-- Faculty News
-- Student Voices
-- Student Spotlight
-- Events, Courses, & Programs
-- Meet the Faculty & Staff
-- Congratulations

Urban Connections: A Comparison Of Connectivity Assessment Methods, Natalie M. Rogers

Environmental Science and Management Professional Master's Project Reports

Habitat connectivity in urban settings is critical for facilitation of safe species movement, species health, and biodiversity. Predicting the movement of wildlife through the urban environment is difficult due to the presence of barriers - natural or built features in the landscape that restrict or prohibit movement of species. Urban properties and greenspaces can serve as pathways of connectivity for wildlife movement across the complex developed matrix. Thus, land managers should assess their properties for possible connectivity functionality to promote safe wildlife movement. Land managers may not be aware of current connectivity assessment methods, therefore this project provides introductory information …

Spatial-Semantic Image Search By Visual Feature Synthesis, Mai Long, Hailin Jin, Chen Fang, Feng Liu

Computer Science Faculty Publications and Presentations

The performance of image retrieval has been improved tremendously in recent years through the use of deep feature representations. Most existing methods, however, aim to retrieve images that are visually similar or semantically relevant to the query, irrespective of spatial configuration. In this paper, we develop a spatial-semantic image search technology that enables users to search for images with both semantic and spatial constraints by manipulating concept text-boxes on a 2D query canvas. We train a convolutional neural network to synthesize appropriate visual features that captures the spatial-semantic constraints from the user canvas query. We directly optimize the retrieval performance …

Rapid Urban Growth And Land Use Patterns In Doha, Qatar: Opportunities For Sustainability, Vivek Shandas, Yasuyo Makido, Salim Ferwati

Urban Studies and Planning Faculty Publications and Presentations

Amidst chaotic growth of Asian cities, the expansion of urban infrastructure in the Middle East’s Gulf region is arguably outpacing any other region on the planet. Yet we have a limited understanding of the types of urban form or the extent to which this rapid urbanization is giving rise to sustainable patterns of growth. We ask, what is the pace and character of urban growth in one Middle East city, Doha, Qatar. By using remotely sensed imagery from 1987 to 2013, we examined the pace, quality, and characteristics of urban growth. We further use the results to create a typology …

The Effect Of Salinity Acclimation On The Upper Thermal Tolerance Threshold Of The European Green Crab, Lauren S. Muñoz-Tremblay, A. L. Kelley, Catherine De Rivera

Environmental Science and Management Faculty Publications and Presentations

Fluctuations in salinity and temperature, among other varying environmental conditions, are stressors in estuaries and may work together to alter the physiological response of organisms that inhabit such environments. Laboratory assessments that investigate how animals respond to multiple environmental stressors can provide an ecological framework for understanding physiological performance across varying conditions. In this study, European green crabs, Carcinus maenas, were collected from Seadrift Lagoon, California, USA (37°54′27.82″N, 122°40′19.56″W) and were lab-acclimated at three different salinity concentrations typical of many estuaries: 15, 25, and 35 PSU at 12 °C (± 1 °C). After acclimation, crabs from each salinity treatment experienced …

Toward A Critical Philosophy For Children, James Funston

PSU McNair Scholars Online Journal

I explore the role of Philosophy for Children (P4C) and critical pedagogy in pre-college education--what is the purpose of engaging with children on philosophical questions and how ought teachers ask such questions? This paper examines the current and past approaches of P4C through the work Brazilian educator Paulo Freire, and attempts to situate P4C within the framework of critical pedagogy, resulting in a synthesis I call "critical P4C." Implementing critical P4C has the capacity to create communities of inquiry around questions of agency and freedom that are central to critical pedagogy. Critical P4C offers strategies for engaging students in discussions …

Mineral Evidence For Generating Compositionally Zoned Rhyolites Of The Devine Canyon Tuff, High Lava Plains, Oregon, Erik Paul Shafer

Dissertations and Theses

Large-volume silicic eruptions are often evacuated from magma reservoirs which display gradients in composition, temperature, crystallinity, and volatile content. The 9.7 Ma Devine Canyon Tuff (DCT) of eastern Oregon represents such an eruption, with >300 km³ of compositionally zoned pyroclastic material deposited as a variably-welded ignimbrite. The ignimbrite displays homogenous bulk tuff major element compositions with a wide range of trace element compositions, allowing for the investigation of how these magmas were generated, stored, and modified in the magma reservoir by studying pumices which represent the primary magmas composing the DCT. Five pumices ranging from dacite to rhyolite bulk compositions …

Rhyolite Petrogenesis At Tower Mountain Caldera, Or, Elizabeth Ann Brown

Dissertations and Theses

Tower Mountain Caldera is the main feature of an Oligocene volcanic field located in the Umatilla National Forest, eastern Oregon. It is perfectly suited to investigate models of rhyolite petrogenesis as all of the important rock components for evaluating generation models are present in a single location and thus are presumably related; basalts, intermediate igneous rocks (which consist of older plutons and younger volcanic rocks, which are ~coeval with rhyolites), metamorphic basement rocks of significant grade, and rhyolites of varying composition. The formation of the caldera produced the Dale Tuff, which comprises the intra-caldera and outflow facies. ⁴⁰Ar/^{39 …}

2017 Commencement Program (Morning Ceremony), Nancy L. Zimpher

Commencement Archives 2010-19

The program for the Portland State University 2017 Commencement morning ceremony (Professional Schools), held at the Moda Center, Portland, Oregon.

Nancy L. Zimpher, Chancellor of the State University of New York, received an honorary doctorate and delivered the commencement address.

2017 Commencement Program (Afternoon Ceremony), Earl Blumenauer

Commencement Archives 2010-19

The program for the Portland State University 2017 Commencement (Afternoon Ceremony: College of Liberal Arts and Sciences).

U.S. Representative Earl Blumenauer received an honorary doctorate and delivered the commencement address.

Analysis And Testing Of A Coaxial Magnetic Gearbox With Flux Concentration Halbach Rotors, Debarupa Som, Kang Li, Joshua Kadel, Jason Wright, Sina Modaresahmadi, Jonathan Bird, W. William

Electrical and Computer Engineering Faculty Publications and Presentations

Halbach array magnetic gearboxes have been discussed as being able to create high torque density. However, Halbach arrays are difficult to mechanically assembly and often the effective air-gap must be made larger in order to provide space for a retaining sleeve. This paper investigates the benefits of using an additional ferromagnetic retaining pole within the Halbach array structure. It is shown that utilizing this flux concentration ferromagnetic pole improves the torque density and can also help retain the magnets in place.

An Examination Of The Relationship Between Professional Development Providers' Epistemological And Nature Of Science Beliefs And Their Professional Development Programs, Alfonso Garcia Arriola

Dissertations and Theses

In the last twenty years in US science education, professional development has emphasized the need to change science instruction from a direct instruction model to a more participatory and constructivist learning model. The result of these reform efforts has seen an increase in science education professional development that is focused on providing teaching strategies that promote inquiry learning to learn science content. Given these reform efforts and teacher responses to professional development, research seems to indicate that whether teachers actually change their practice may depend on the teachers' basic epistemological beliefs about the nature of science. The person who builds …

Ecosystem Recovery In Estuarine Wetlands Of The Columbia River Estuary, Sarah Ann Kidd

Dissertations and Theses

In the restoration of tidal wetland ecosystems, potential drivers of plant community development range from biotic controls (e.g. plant competition, seed dispersal) to abiotic controls (e.g. tidal flooding, salinity levels). How these controls influence the success of tidal wetland restoration are only partly understood, but have important implications for wetland habitat recovery. Specifically, the extent to which the existing native and non-native seed banks in tidally reconnected wetlands interact with these controls is not clear, yet the potential success of passive restoration methods depends upon this understanding.

For a 54-year chronosequence of eleven tidal wetland restoration sites in the Lower …

Analyzing Dam Feasibility In The Willamette River Watershed, Alexander Cameron Nagel

Dissertations and Theses

This study conducts a dam-scale cost versus benefit analysis in order to explore the feasibility of each the 13 U.S. Army Corps of Engineers (USACE) commissioned dams in Oregon’s Willamette River network. Constructed between 1941 and 1969, these structures function in collaboration to comprise the Willamette River Basin Reservoir System (WRBRS). The motivation for this project derives from a growing awareness of the biophysical impacts that dam structures can have on riparian habitats. This project compares each of the 13 dams being assessed, to prioritize their level of utility within the system. The study takes the metrics from the top …

Investigation In To The Stabilizing Effects Of The Modified Base Archaeosine In Trna And The Identification Of The Fluorescent Product Of Base Treatment Of Nad(P)+ Cofactors, Ben Turner

Dissertations and Theses

This dissertation covers two projects linked by their involvement in the modification of tRNA bases.

The first project focused on an investigation of a role for the modified base Archaeosine, the ubiquitous modification in tRNA in the archaeal domain. Initial work was performed on a set of in vitro prepared tRNA modified to feature either the canonical guanine base at position 15, preQ₀ (TGT product) or Archaeosine (ArcS product). There was very little difference in the thermal stability of tRNAs containing these modifications in the halophilic H. volcanii tRNA^Ser or E. coli tRNA^Gln. In tRNA^{Gln …}

The Camkii Holoenzyme Structure In Activation Competent Conformations, Janette B. Myers, Vincent Zaegel, Steven J. Coultrap, Adam P. Miller, K. Ulrich Bayer, Steve L. Reichow

Chemistry Faculty Publications and Presentations

The Ca²⁺/calmodulin-dependent protein kinase II (CaMKII) assembles into large 12-meric holoenzymes, which is thought to enable regulatory processes required for synaptic plasticity underlying learning, memory and cognition. Here we used single particle electron microscopy (EM) to determine a pseudoatomic model of the CaMKIIα holoenzyme in an extended and activation-competent conformation. The holoenzyme is organized by a rigid central hub complex, while positioning of the kinase domains is highly flexible, revealing dynamic holoenzymes ranging from 15–35 nm in diameter. While most kinase domains are ordered independently, ~20% appear to form dimers and

Using Critical Physical Geography To Map The Unintended Consequences Of Conservation Management Programs, Melanie Malone

Dissertations and Theses

A variety of conservation trends have gained and lost favor throughout the years in agriculture, with U.S. Farm Bills often influencing what conservation practices are implemented by farming communities throughout the U.S. This dissertation focuses on the unintended consequences of conservation management practices in the Fifteenmile Watershed of Wasco County, Oregon. Specifically, I seek to address how farmer enrollment in various conservation techniques, loosely defined as no-till agriculture, has affected soil and water quality through the increased use of herbicide, and subsequently rendered ecological and human health vulnerable. Using a critical physical geography framework, I address both the biophysical factors …

Fully Generic Programming Over Closed Universes Of Inductive-Recursive Types, Larry Diehl

Dissertations and Theses

Dependently typed programming languages allow the type system to express arbitrary propositions of intuitionistic logic, thanks to the Curry-Howard isomorphism. Taking full advantage of this type system requires defining more types than usual, in order to encode logical correctness criteria into the definitions of datatypes. While an abundance of specialized types helps ensure correctness, it comes at the cost of needing to redefine common functions for each specialized type. This dissertation makes an effort to attack the problem of code reuse in dependently typed languages. Our solution is to write generic functions, which can be applied to any datatype.

Such …

Columbia River Basin Salmon And Steelhead Long-Term Recovery Situation Assessment, Oregon Solutions, William D. Ruckelshaus Center

National Policy Consensus Center Publications

In the fall of 2012, after consulting with a wide range of salmon recovery partners, NOAA Fisheries asked Oregon Consensus and the William D. Ruckelshaus Center (university-based, neutral, third-party institutions devoted to promoting collaborative governance and consensusbased public policy) to conduct an independent, impartial situation assessment to explore regional views about how best to approach comprehensive, long-term salmon and steelhead recovery in the Basin. The centers assembled an Assessment Team comprised of practitioners and academics from Washington, Oregon and Idaho.

The Assessment Team conducted 206 semi-structured interviews with individuals selected for their knowledge of, engagement in, and/or concern for salmon …

Advancing Rationality With Sustainability: An Analysis Of Agent-Based Simulation, Osman Goktug Tanrikulu

Hatfield Graduate Journal of Public Affairs

Today, falling trends of species and ecosystem in the world due to overconsumption and destruction of natural resources are at critical levels. It is vital for humanity to operate with sustainable and resilient modes of production and consumption. In this regard, this paper examines the basic premise of rationality and introduces sustainability as an advancement to the theoretical concept of rationality. Thus, a rational mindset and a sustainable mindset are compared under depletion of environmental resources. The understanding of rationality in the analysis is based on Garett Hardin’s (1968) ‘the tragedy of the commons’ model, in which actors are self-interested …

African American Teacher Recruitment: A Case Study In Oregon, Deborah Miller Allen

Dissertations and Theses

The public school teacher population of the United States is predominantly White, while the demographics of P-12 student population continue to grow increasingly diverse. Across the nation, there has been a call for the recruitment and retention of culturally and linguistically diverse teachers. The state of Oregon passed the Oregon Educator Equity Act, originally called the Oregon Minority Teacher Act, in 1991, and with recent renewed attention, the preparation of more culturally and linguistically diverse teachers in the state has gained prominence. Refocused consideration to the lack of diversity in the teaching workforce is overdue, as evidenced by the low …

Middle School Teacher Beliefs About Classroom Diversity And Their Influence On Differentiated Instructional Practices, Marcus Fredrick-Lynn Wenzel

Dissertations and Theses

Diversity across U.S. classrooms is on the rise which is leading to renewed calls for teachers to meet individual learning needs. Studies indicate the failure to address individual learning needs can lead to higher rates of student disengagement, off-task behaviors, and diminished learning outcomes. Differentiated instruction is an approach to teaching that meets the growing diversity of individual learning needs by considering students' readiness, interest, and learning styles. Differentiated instructional approaches help teachers meet individual learning needs by allowing them to modify instruction as needed. However, despite the apparent benefits of differentiated instruction, teachers are hesitant to abandon other educational …

Investigation Of Ambient Reactive Nitrogen Emissions Sources And Deposition In The Columbia River Gorge National Scenic Area, Jacinda L. Mainord

Dissertations and Theses

Anthropogenic reactive nitrogen is emitted into the atmosphere from fossil fuel combustion (nitrogen oxides) and agricultural activities (nitrogen oxides and ammonia). Nitrogen oxide emissions have long been controlled for their role in ambient air pollution and human health effects. However, reactive nitrogen deposition is less understood even though it can play a significant role in altering biodiversity, impairing ecosystem and biogeochemical function and degrading cultural artifacts. Although nitrogen deposition is a natural part of biogeochemical cycling, many ecosystems across the United States are at risk of exceeding the critical nitrogen deposition load. While nitrogen oxides are routinely measured in urban …

Design And Application Of A 3d Photocatalyst Material For Water Purification, Simon Paul Fowler

Dissertations and Theses

This dissertation presents a method for enhancement of the efficiency and scalability of photocatalytic water purification systems, along with an experimental validation of the concept. A 3-dimensional photocatalyst structure, made from a TiO₂-SiO₂ composite, has been designed and fabricated for use in a custom designed LED-source illumination chamber of rotational symmetry that corresponds with the symmetry of the photocatalyst material. The design of the photocatalyst material has two defining characteristics: geometrical form and material composition. The design of the material was developed through the creation of a theoretical model for consideration of the system's photonic efficiency. Fabrication …

Mapping Meaningful Places On Washington’S Olympic Peninsula: Toward A Deeper Understanding Of Landscape Values, Lee Cerveny, Kelly Biedenweg, Rebecca J. Mclain

Institute for Sustainable Solutions Publications and Presentations

Landscape values mapping has been widely employed as a form of public participation GIS (PPGIS) in natural resource planning and decision-making to capture the complex array of values, uses, and interactions between people and landscapes. A landscape values typology has been commonly employed in the mapping of social and environmental values in a variety of management settings and scales. We explore how people attribute meanings and assign values to special places on the Olympic Peninsula (Washington, USA) using both a landscape values typology and qualitative responses about residents’ placerelationships. Using geographically referenced social values data collected in community meetings (n …

Cascadia Subduction Tremor Muted By Crustal Faults, Ray E. Wells, Richard J. Blakely, Aaron G. Wech, Patricia A. Mccrory, Andrew Michael

Geology Faculty Publications and Presentations

Deep, episodic slow slip on the Cascadia subduction megathrust of western North America is accompanied by low-frequency tremor in a zone of high fluid pressure between 30 and 40 km depth. Tremor density (tremor epicenters per square kilometer) varies along strike, and lower tremor density statistically correlates with upper plate faults that accommodate northward motion and rotation of forearc blocks. Upper plate earthquakes occur to 35 km depth beneath the faults. We suggest that the faults extend to the overpressured megathrust, where they provide fracture pathways for fluid escape into the upper plate. This locally reduces megathrust fluid pressure and …

Generalized Differential Calculus And Applications To Optimization, R. Blake Rector

Dissertations and Theses

This thesis contains contributions in three areas: the theory of generalized calculus, numerical algorithms for operations research, and applications of optimization to problems in modern electric power systems. A geometric approach is used to advance the theory and tools used for studying generalized notions of derivatives for nonsmooth functions. These advances specifically pertain to methods for calculating subdifferentials and to expanding our understanding of a certain notion of derivative of set-valued maps, called the coderivative, in infinite dimensions. A strong understanding of the subdifferential is essential for numerical optimization algorithms, which are developed and applied to nonsmooth problems in operations …

Towards Systematic Prediction Of Urban Heat Islands: Grounding Measurements, Assessing Modeling Techniques, Jackson Voelkel, Vivek Shandas

Urban Studies and Planning Faculty Publications and Presentations

While there exists extensive assessment of urban heat, we observe myriad methods for describing thermal distribution, factors that mediate temperatures, and potential impacts on urban populations. In addition, the limited spatial and temporal resolution of satellite-derived heat measurements may limit the capacity of decision makers to take effective actions for reducing mortalities in vulnerable populations whose locations require highly-refined measurements. Needed are high resolution spatial and temporal information for urban heat. In this study, we ask three questions: (1) how do urban heat islands vary throughout the day? (2) what statistical methods best explain the presence of temperatures at sub-meter …