Digital Commons Network^™

An Evaluation Of Data Collected By Middle School And College-Level Students In Stream Channel Geomorphic Assessment, Martin D. Lafrenz

Geography Faculty Publications and Presentations

This project tested the accuracy and repeatability of geomorphic stream channel assessments conducted by two different middle school classes from the Walt Morey Middle School in Troutdale, OR and college students from Portland State University in Portland, OR. Each group surveyed the same three cross-sections in Fairview Creek, a tributary to the Lower Columbia River, in order to assess stream channel geometry, discharge, composition of the bed material, and water quality. The three student groups were all able to accurately document the stream channel geometry, including stream width and mean depth, indicating that these data can be successfully collected by …

Do Cryoconite Holes Have The Potential To Be Significant Sources Of C, N, And P To Downstream Depauperate Ecosystems Of Taylor Valley, Antarctica?, Elizabeth A. Bagshaw, Martyn Tranter, Andrew G. Fountain, Kathleen A. Welch, Hassan J. Basagic, W. Berry Lyons

Geology Faculty Publications and Presentations

Nutrient recycling occurs in hydrologically isolated cryoconite holes on the glaciers of the McMurdo Dry Valleys, Antarctica. Biogeochemical processes enrich the cryoconite holes with solute and nutrients compared to the source sediment and glacier ice. The position of the glacier within the landscape affects the physical and biogeochemical character of the cryoconite holes, with those found in more biologically productive areas of the valley having higher concentrations of C, N, and P and higher pH. Comprehensive assessment of the quality and quantity of bioavailable C, N, and P shows that the cryoconite holes represent a significant store of nutrient in …

Strain Energy Release From The 2011 9.0 Mw Tōhoku Earthquake, Japan, Kenneth M. Cruikshank, Curt D. Peterson

Geology Faculty Publications and Presentations

The purpose of this paper is to compare the strain energy released due to elastic rebound of the crust from the tragic 2011 9.0 Mw Tōhoku earthquake in Japan with the observed radiated seismic energy. The strain energy was calculated by analyzing coseismic displacements of 1024 GPS stations of the Japanese GEONET network. The value of energy released from the analysis is 1.75 × 1017 J, which is of the same order of magnitude as the USGS-observed radiated seismic energy of 1.9 × 1017 Nm (J). The strain energy method is independent of seismic methods for determining the energy released …

Filling In Missing Values In The North Dakota Land Valuation Model, Laura Beth Laufmann

Agribusiness and Applied Economics

The North Dakota Land Valuation Model relies on a crop yield data set published by the USDA's National Agricultural Statistics Service. Over the years this data set, due to the way in which the data is collected, has developed a growing problem with missing values. This research utilizes a secondary data set and the spatial nature of the crop yield data to develop a new methodology for interpolating the missing values in the NASS data set. This methodology uses the secondary data set to establish the spatial nature of the yield data and to build spatial weights matrices. These spatial …

Investigation Of The International Food-Grade Soybean Market, Changmin Kim

Agribusiness and Applied Economics

This study provides an overview of the international soybean market and takes a look at a case study of an exporter and their target markets, China, Japan, and South Korea. Then it estimates future soybean import demands for these countries. Results indicate that China’s soybean import demand will remarkably increase compared with those in Japan and South Korea. Although Korean and Japanese buyers are willing to pay a premium for food-grade soybeans, China market may grow faster than those in Japan and South Korea. This is because as income increases, Chinese consumer may concern more about their health which makes …

Developing A Model To Value Germplasm Using Real Options, Marit Simonson-Paschke

Agribusiness and Applied Economics

With many varieties of germplasm being developed, it is imperative to the industry that firms decide on a valuation method. This need to include looking at traits of the germplasm, the risk and uncertainty of expected returns associated with a varieties' development and release. The purpose of this thesis is to determine the option value of developing germplasm using the real options approach. The value gained of the variety will be measured and used as a decision factor in the determining the value of the germplasm at different development phases. This approach helps managers decide the best possible option in …

Intermarket Trading Strategies And Risk, Kristopher Douglas Skadberg

Agribusiness and Applied Economics

The purpose of this thesis is to research methods that will be used to discover the profitability and risk of spatially arbitraging soybeans. A portfolio is used to analyze trading strategies, and the dependence measures is critical when simulating all of the variables. The dependence measures will aid in selecting the appropriate assets for the portfolio. The profits and risks for each asset will be analyzed and an optimization procedure will weigh the assets appropriately in bushels. Strategizing has become very important for merchandisers, because of the added risk associated with trading commodities. The results indicate that spatial arbitrage profits …

Nous And Aisthēsis: Two Cognitive Faculties In Aristotle, Adriana Renero

Publications and Research

In disagreement with Claudia Baracchi's controversial thesis that there is a 'simultaneity and indissolubility' if not an 'identity' of intelligence (nous) and perception (aisthēsis) at the core of Aristotle's philosophy, I will argue that Aristotle maintains a fundamental distinction between these cognitive faculties. My goal in this paper is to examine specific parts of two central and complex passages, VI.8, 1142al2-30 and VI. 11, 1143a33-bl5, from the Nicomachean Ethics to show that Baracchi's view is unpersuasive. I will show that Aristotle considers nous to be a different capacity than mere perception and one through which particulars …

Developing And Assessing Curriculum On The Physics Of Medical Instruments, Warren Christensen, James K. Johnson, Grace R. Van Ness, Elliot E. Mylott, Justin C. Dunlap, Elizabeth A. Anderson, Ralf Widenhorn

Physics Faculty Publications and Presentations

Undergraduate educational settings often struggle to provide students with authentic biologically or medically relevant situations and problems that simultaneously improve their understanding of physics. Through exercises and laboratory activities developed in an elective Physics in Biomedicine course for upper-level biology or pre–health majors at Portland State University, we aim to teach fundamental physical concepts, such as light absorption and emission and atomic energy levels, through analysis of biological systems and medical devices. The activities address the properties of electromagnetic waves as they relate to the interaction with biological tissue and make links between physics and biomedical applications such as microscopy …

A Conversation On Judicial Decision Making, Robin Cooper Feldman

Faculty Scholarship

No abstract provided.

Gauge Field Preheating At The End Of Inflation, J. Tate Deskins, John T. Giblin Jr., Robert R. Caldwell

Dartmouth Scholarship

Here we consider the possibility of preheating the Universe via the parametric amplification of a massless, U(1) abelian gauge field. We assume that the gauge field is coupled to the inflaton via a conformal factor with one free parameter. We present the results of high-resolution three-dimensional simulations of this model and show this mechanism efficiently preheats the Universe to a radiation-dominated final state.

Vegetative Filter Strip: A Best Management Practice (Bmp) For Feedlot Runoff Pollution Control In North Dakota, Md. Atikur Rahman

Agribusiness and Biosystems Engineering

Runoff from animal feeding operations is a major source of water pollution. Vegetative filter strips (VFS) are effective ways to reduce nonpoint source pollution. In this study, vegetative filter strips with different designs and in climatic and management conditions of North Dakota were evaluated. Runoff samples were collected from inflow (before entering VFS) and outflow (after exiting the VFS) locations using automatic samplers. Collected samples were analyzed for solids and nutrients. It was observed that the transport reductions by VFS were ranged from very low to up to 100%. However, soluble nutrients were not as effectively removed as sediment and …

Non-Destructive Analysis Of Single Plant Canola (Brassica Napus) Seed Using Near Infrared Spectroscopy, Harjot Sidhu

Agribusiness and Biosystems Engineering

Near Infrared Spectroscopy (NIRS) is widely used for quantitative analysis of oilseeds in a non-destructive manner. Canola (Brassica napus) is a popular oilseed crop that is used for food and biofuel markets. Due to limited seed availability in plant breeding programs, single plant analysis is often preferred. An NIRS commercial calibration model was evaluated to predict single plant canola seed, but the results showed the need for new NIRS calibration models to predict moisture content, oil content, and fatty acid content for single plant canola seed (3 g) with minimal sample preparation. A separate NIRS calibration model was developed for …

A Call To Action: What Student Teachers Can Teach Us, Kathleen M. Cowin

Northwest Journal of Teacher Education

This qualitative study uses six years of survey data, collected from student teachers in a graduate level university initial teacher licensure program, to illuminate student teachers’ experiences with their cooperating teachers during their student teaching internship. The data, comments made by student teachers about their experiences with their cooperating teachers, were used to answer this research question: What are student teachers telling us about their experiences with their cooperating teachers? Using the constant comparative method of qualitative analysis (Glaser & Strauss, 1967) the survey data consisting of answers to the open form question “My cooperating teacher could have been more …

Spatial And Temporal Patterns Of Amphibian Chytrid Fungus Batrachochytrium Dendrobatidis Occupancy In Amphibian Habitats, Tara Chestnut

Environmental Science and Management Professional Master's Project Reports

Chytrid fungi are the most ancestral of the fungi and are global in distribution. There are over 1200 species of Chytridiomycota described from freshwater, marine and terrestrial systems in temperate, tropical and tundra environments. Chytridiales are characterized by a range of morphologies and share the flask- or pot-like shape of the zoosporangia, within which motile zoospores develop. Chytrids function primarily as plant saprobes and parasites, but some also parasitize animals. Chytrids are observed in conjunction with the decline of freshwater and marine algal blooms, they decompose excess pollen, and comprise the fungal flora in gut of herbivores. Some chytrids also …

Understanding The Drivers Of Forest, Residential, And Agricultural Land Values In Yamhill County Using Hedonic Models, Emily D. Dietrich

Environmental Science and Management Professional Master's Project Reports

Hedonic modeling is commonly used in land and property value estimations in an attempt to identify the impact that various attributes have on the market value of that property. The purpose of this study is to examine the factors contributing to land value of agricultural, forest, and residential properties in Yamhill County, as part of the Spatial Ecosystem Services Analysis, Modeling, and Evaluation (SESAME, http://www.pdx.edu/ecosystem-services/) project. This paper discusses the process and preliminary results of the development of hedonic models that will be utilized for predicting land value changes under future land conversion scenarios. Applying the models to future scenarios …

Yet Another Crisis Of The Book, Bennett Gilbert

University Studies Faculty Publications and Presentations

Book bindings and binding decor can reveal deep parts of our attitudes toward books and toward culture. Changes in attitudes toward the codex book during the French Revolution and the Industrial Revolution are part of continual change in book culture. The re-binding of early printed books is exemplary evidence of these changes. The new bindings express both a rejection of pre-Enlightenment culture and an attempt to stabilize traditional cultural values. This also suggests how we might view events customarily considered to be "revolutions".

Daily Temperature Fluctuations Unpredictably Influence Developmental Rate And Morphology At A Critical Early Larval Stage In A Frog, Juliana M. Arrighi, Ezra S. Lencer, Advait Jukar, Daesik Park, Patrick C. Phillips, Robert H. Kaplan

Complex Systems Faculty Publications and Presentations

Background: Environmental temperature has profound consequences for early amphibian development and many field and laboratory studies have examined this. Most laboratory studies that have characterized the influence of temperature on development in amphibians have failed to incorporate the realities of diel temperature fluctuations (DTF), which can be considerable for pond-breeding amphibians.

Results: We evaluated the effects of different ecologically relevant ranges of DTF compared with effects of constant temperatures on development of embryos and larvae of the Korean fire-bellied toad (Bombina orientalis). We constructed thermal reaction norms for developmental stage, snout- vent length, and tail length by fitting …

Grasping The Wind?Aesthetic Participation, Between Cognition And Immersion, Mădălina Diaconu

Contemporary Aesthetics (Journal Archive)

No abstract provided.

Trace-Element And Physical Response To Melt Percolation In Summit (Greenland) Snow, Gifford J. Wong, Robert L. Hawley, Eric R. Lutz, Erich C. Osterberg

Dartmouth Scholarship

Surface melt on a glacier can perturb the glaciochemical record beyond the natural variability. While the centre of the Greenland ice sheet is usually devoid of surface melt, many high- Arctic and alpine ice cores document frequent summertime melt events. Current hypotheses interpreting melt-affected ice-core chemistry rely on preferential elution of certain major ions. However, the precise nature of chemistry alteration is unknown because it is difficult to distinguish natural variability from melt effects in a perennially melt-affected site. We use eight trace-element snow chemistry records recovered from Summit, Greenland, to study spatial variability and melt effects on insoluble trace …

Stability Of Large Flocks: An Example, J. J. P. Veerman, F. M. Tangerman

Mathematics and Statistics Faculty Publications and Presentations

The movement of a flock with a single leader (and a directed path from it to every agent) can be stabilized. Nonetheless for large flocks perturbations in the movement of the leader may grow to a considerable size as they propagate throughout the flock and before they die out over time. As an example we consider a string of N+1 oscillators moving in the line. Each one `observes' the relative velocity and position of only its nearest neighbors. This information is then used to determine its own acceleration. Now we fix all parameters except the number of oscillators. We then …

Automated Extraction And Classification Of Time-Frequency Contours In Humpback Vocalizations, Hui Ou, Whitlow W.L. Au, Lisa M. Zurk, Marc O. Lammers

Electrical and Computer Engineering Faculty Publications and Presentations

A time-frequency contour extraction and classification algorithm was created to analyze humpback whale vocalizations. The algorithm automatically extracted contours of whale vocalization units by searching for gray-level discontinuities in the spectrogram images. The unit-to-unit similarity was quantified by cross-correlating the contour lines. A library of distinctive humpback units was then generated by applying an unsupervised, cluster-based learning algorithm. The purpose of this study was to provide a fast and automated feature selection tool to describe the vocal signatures of animal groups. This approach could benefit a variety of applications such as species description, identification, and evolution of song structures. The …

Meaningful Sustainability Learning: An Action Research Study Of Sustainability Pedagogy In Two University Courses, Heather Burns

Educational Leadership and Policy Faculty Publications and Presentations

Educators are increasingly aware of the importance of sustainability and the need to educate for sustainable change within higher education. This article addresses the growing need to focus on how teaching and learning can be re-oriented towards sustainability, and more specifically how educators can effectively address increasingly well-known sociocultural and ecological problems in ways that transform learners and empower them to make change based on a sense of civic responsibility and sustainability. This research study draws on the Burns Model of Sustainability Pedagogy, which integrates ecological design, systemic and interdisciplinary learning, multiple perspectives, an active and engaged learning process, and …

An Assessment Of Integrated Weed Management Strategies For Purple Threeawn-Dominated Rangelands, Nickolas Alois Dufek

Range Science

Purple threeawn (Aristida purpurea Nutt.) is a native bunch grass that is avoided by grazers. It is capable of dominating old cropland and overgrazed pastures, limiting livestock carrying capacity, and degrading wildlife habitat. Traditional management tools have had little impact on threeawn dominance in semiarid regions of the west. Our objectives were to: 1) assess fire and nitrogen treatment effects on threeawn forage quality at various phenological stages to test their potential as pretreatments in a grazing strategy and 2) examine a threeawn-dominated plant community’s response to prescribed fire, nitrogen addition, and clipping. Fire improved threeawn forage quality with greater …

Online Learning In A Chemical Perceptron, Peter Banda, Christof Teuscher, Matthew R. Lakin

Computer Science Faculty Publications and Presentations

Autonomous learning implemented purely by means of a synthetic chemical system has not been previously realized. Learning promotes reusability and minimizes the system design to simple input-output specification. In this article we introduce a chemical perceptron, the first full-featured implementation of a perceptron in an artificial (simulated) chemistry. A perceptron is the simplest system capable of learning, inspired by the functioning of a biological neuron. Our artificial chemistry is deterministic and discrete-time, and follows Michaelis-Menten kinetics. We present two models, the weight-loop perceptron and the weight-race perceptron, which represent two possible strategies for a chemical implementation of linear integration and …

A Transformation-Based Approach To Implication Of Gste Assertion Graphs, Gouwu Yang, William N. N. Hung, Xiaoyu Song, Wensheng Guo

Electrical and Computer Engineering Faculty Publications and Presentations

Generalized symbolic trajectory evaluation (GSTE) is a model checking approach and has successfully demonstrated its powerful capacity in formal verification of VLSI systems. GSTE is an extension of symbolic trajectory evaluation (STE) to the model checking of -regular properties. It is an alternative to classical model checking algorithms where properties are specified as finite-state automata. In GSTE, properties are specified as assertion graphs, which are labeled directed graphs where each edge is labeled with two labeling functions: antecedent and consequent. In this paper, we show the complement relation between GSTE assertion graphs and finite-state automata with the expressiveness of regular …

What Work Samples Reveal About Secondary Pre-Service Social Studies Teachers' Use Of Literacy Strategies, Susan J. Lenski, Gayle Y. Thieman

Education Faculty Publications and Presentations

The article discusses a study which aims to answer the research questions of whether secondary social studies pre-service teachers incorporate literacy strategies in their work samples during student teaching, and the extent and conditions secondary social studies pre-service teachers use higher levels of literacy strategies in their work samples. The study is framed within 3 areas of research namely activity theory, work sample methodology and disciplinary literacy.

Fraction Proficiency And The Number Line, Jeanne Elizabeth Bass

LSU Master's Theses

The Common Core State Standards place special emphasis on developing fraction proficiency and the use of the number line, especially in grades three through five, whereas the previously mandated “Louisiana Comprehensive Curriculum” put lower priority on fractions and gave little attention to the number line as a model for fractions. The present study was performed in several 6th-grade math classrooms in rural Louisiana. We piloted fraction proficiency tests that were intended to check basic vocabulary and student access to various fraction models, as expected in the Common Core. Some strong error patterns were observed. They might be related to difference …

On The Role Of Shape Prototypes In Hierarchical Models Of Vision, Michael David Thomure, Melanie Mitchell, Garrett T. Kenyon

Computer Science Faculty Publications and Presentations

We investigate the role of learned shape-prototypes in an influential family of hierarchical neural-network models of vision. Central to these networks’ design is a dictionary of learned shapes, which are meant to respond to discriminative visual patterns in the input. While higher-level features based on such learned prototypes have been cited as key for viewpointinvariant object-recognition in these models [1], [2], we show that high performance on invariant object-recognition tasks can be obtained by using a simple set of unlearned, “shape-free” features. This behavior is robust to the size of the network. These results call into question the roles of …

Consciousness As Integrated Information: A Provisional Philosophical Critique, Anthony F. Peressini

Philosophy Faculty Research and Publications

Giulio Tononi (2008) has offered his integrated information theory of consciousness (IITC) as a ‘provisional manifesto’. I critically examine how the approach fares. I point out some (relatively) internal concerns with the theory and then more broadly philosophical ones; finally I assess the prospects for IITC as a fundamental theory of consciousness. I argue that the IITC’s scientific promise does carry over to a significant extent to broader philosophical theorizing about qualia and consciousness, though not as directly as Tononi suggests, since the account is much more focused on the qualitative character of experience rather than on consciousness itself. I …