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Bioelectrical Impedance Analysis As A Laboratory Activity: At The Interface Of Physics And The Body, Elliot Mylott, Ellynne Marie Kutschera, Ralf Widenhorn Feb 2014

Bioelectrical Impedance Analysis As A Laboratory Activity: At The Interface Of Physics And The Body, Elliot Mylott, Ellynne Marie Kutschera, Ralf Widenhorn

Physics Faculty Publications and Presentations

We present a novel laboratory activity on RC circuits aimed at introductory physics students in life-science majors. The activity teaches principles of RC circuits by connecting ac-circuit concepts to bioelectrical impedance analysis (BIA) using a custom-designed educational BIA device. The activity shows how a BIA device works and how current, voltage, and impedance measurements relate to bioelectrical characteristics of the human body. From this, useful observations can be made including body water, fat-free mass, and body fat percentage. The laboratory is engaging to pre-health and life-science students, as well as engineering students who are given the opportunity to observe electrical …


Surface Plasmons Of A Graphene Parallel Plate Waveguide Bounded By Kerr-Type Nonlinear Media, H. Hajian, A. Soltani-Vala, M. Kalafi, Pui T. Leung Feb 2014

Surface Plasmons Of A Graphene Parallel Plate Waveguide Bounded By Kerr-Type Nonlinear Media, H. Hajian, A. Soltani-Vala, M. Kalafi, Pui T. Leung

Physics Faculty Publications and Presentations

The exact dispersion relations of the transverse magnetic surface plasmons (SPs) supported by a graphene parallel plate waveguide (PPWG), surrounded on one or both sides by Kerr-type nonlinear media, are obtained analytically. It is shown that if self-focusing nonlinear materials are chosen as the surrounding media, the SPs localization length (LL) is decreased, while their propagation length (PL) remains unchanged, as compared to those of a typical graphene PPWG. Moreover, PL and LL of the SPs are considerably affected by adjusting nonlinear parts of the dielectric permittivities of the nonlinear media. It is found that using an appropriate defocusing nonlinear …


The Influence Of Recurrent Modes Of Climate Variability On The Occurrence Of Winter And Summer Extreme Temperatures Over North America, Paul C. Loikith, Anthony J. Broccoli Feb 2014

The Influence Of Recurrent Modes Of Climate Variability On The Occurrence Of Winter And Summer Extreme Temperatures Over North America, Paul C. Loikith, Anthony J. Broccoli

Geography Faculty Publications and Presentations

The influence of the Pacific–North American (PNA) pattern, the northern annular mode (NAM), and the El Ni~no–Southern Oscillation (ENSO) on extreme temperature days and months over North America is examined. Associations between extreme temperature days and months are strongest with the PNA and NAM andweaker for ENSO. In general, the associationwith extremes tends to be stronger onmonthly than daily time scales and for winter as compared to summer. Extreme temperatures are associated with the PNAandNAMin the vicinity of the centers of action of these circulation patterns; however, many extremes also occur on days when the amplitude and polarity of these …


Historical Vegetation Of The Tiller Area, Douglas County, Oregon Based On Glo Survey Notes, O. Eugene Hickman, John Christy Jan 2014

Historical Vegetation Of The Tiller Area, Douglas County, Oregon Based On Glo Survey Notes, O. Eugene Hickman, John Christy

Institute for Natural Resources Publications

This project was conducted in the Tiller area east of Canyonville, to develop a landscape perspective of historical vegetation for the early settlement era. The project area covered about 128,214 acres, of which 42% was private land, 17% BLM, and 41% USFS. This area of complex topography, transitional between interior valleys of the Umpqua River and the Cascade Range, has a small rural population base sometimes impacted by local natural resource problems and management. The study area includes portions of the South Douglas County Wildland-Urban Interface zone.

Historical land survey notes from General Land Office (GLO) were used to create …


Development Of A Steady-State River Hydrodynamic And Temperature Model Based On Ce-Qual-W2, Wenwei Xu Jan 2014

Development Of A Steady-State River Hydrodynamic And Temperature Model Based On Ce-Qual-W2, Wenwei Xu

Dissertations and Theses

CE-QUAL-W2 is a 2-D hydrodynamic and water quality model that has been applied to reservoirs, lakes, river systems, and estuaries throughout the world. However, when this model is applied for shallow systems, this model requires a long calculation time to maintain numerical stability, compared to applications of reservoirs or deeper river systems.

To solve this problem, a new hydrodynamic and temperature model was built based on the framework of CE-QUAL-W2 but that allows for steady-state hydrodynamic computations. By calculating the hydrodynamics at steady-state, the time step for stability is relaxed and simulations can proceed at much higher time steps. The …


Project Nano: Will Allowing High School Students To Use Research Grade Scanning Electron Microscopes Increase Their Interest In Science?, Leslie Teneyck Smith Jan 2014

Project Nano: Will Allowing High School Students To Use Research Grade Scanning Electron Microscopes Increase Their Interest In Science?, Leslie Teneyck Smith

Dissertations and Theses

In this study, one AP Biology curriculum unit and one general Biology curriculum unit that included tabletop Scanning Electron Microscope (SEM) technology provided by Project NANO, a grant-funded, collaborative initiative designed to integrate cutting-edge nanotechnology into high school classrooms were implemented at a public high school in rural Oregon. Nine students participated in the AP unit and 52 students participated in the general Biology unit. Each student completed an opinion-based pre and post survey to determine if using the SEM as a part of the curriculum unit had an impact on his or her interest in science or in nanoscience. …


A Review Of Urban Water Body Challenges And Approaches: (1) Rehabilitation And Remediation, Robert M. Hughes, Susie Dunham, Kathleen G. Maas-Hebner, J. Alan Yeakley, Carl B. Schreck, Michael Harte, Nancy Molina, Clinton C. Shock, Victor W. Kaczynski, Jeff Schaeffer Jan 2014

A Review Of Urban Water Body Challenges And Approaches: (1) Rehabilitation And Remediation, Robert M. Hughes, Susie Dunham, Kathleen G. Maas-Hebner, J. Alan Yeakley, Carl B. Schreck, Michael Harte, Nancy Molina, Clinton C. Shock, Victor W. Kaczynski, Jeff Schaeffer

Environmental Science and Management Faculty Publications and Presentations

We review how urbanization alters aquatic ecosystems, as well as actions that managers can take to remediate urban waters. Urbanization affects streams by fundamentally altering longitudinal and lateral processes that in turn alter hydrology, habitat, and water chemistry; these effects create physical and chemical stressors that in turn affect the biota. Urban streams often suffer from multiple stressor effects that have collectively been termed an “urban stream syndrome,” in which no single factor dominates degraded conditions. Resource managers have multiple ways of combating the urban stream syndrome. These approaches range from whole-watershed protection to reach-scale habitat rehabilitation, but the prescription …


Learning General Features From Images And Audio With Stacked Denoising Autoencoders, Nathaniel H. Nifong Jan 2014

Learning General Features From Images And Audio With Stacked Denoising Autoencoders, Nathaniel H. Nifong

Dissertations and Theses

One of the most impressive qualities of the brain is its neuro-plasticity. The neocortex has roughly the same structure throughout its whole surface, yet it is involved in a variety of different tasks from vision to motor control, and regions which once performed one task can learn to perform another. Machine learning algorithms which aim to be plausible models of the neocortex should also display this plasticity. One such candidate is the stacked denoising autoencoder (SDA). SDA's have shown promising results in the field of machine perception where they have been used to learn abstract features from unlabeled data. In …


Revisiting Volcanology And Composition Of Rhyolites And Associated Ree Rich Mafic Clasts Of The Three Fingers Caldera, Se Oregon, Phillip Ira Marcy Jan 2014

Revisiting Volcanology And Composition Of Rhyolites And Associated Ree Rich Mafic Clasts Of The Three Fingers Caldera, Se Oregon, Phillip Ira Marcy

Dissertations and Theses

Two adjacent caldera systems, the Mahogany Mountain and the Three Fingers caldera constitute voluminous rhyolitic volcanic deposits on the eastern margin of the Oregon-Idaho graben during the middle-Miocene. Both calderas are part of the Lake Owyhee volcanic field that in turn is part of widespread rhyolite deposits associated with the Columbia River Basalt province. We focus on establishing relationships between intracaldera units of Three Fingers caldera and caldera-forming tuff of Spring Creek and surveying the distribution of entrained mafic clasts which often display anomalous concentrations of rare earth elements.

Previous mapping identified two intra-caldera facies and one outflow facies of …


Fish Species Introductions Provide Novel Insights Into The Patterns And Drivers Of Phylogenetic Structure In Freshwaters, Angela L. Strecker, Julian D. Olden Jan 2014

Fish Species Introductions Provide Novel Insights Into The Patterns And Drivers Of Phylogenetic Structure In Freshwaters, Angela L. Strecker, Julian D. Olden

Environmental Science and Management Faculty Publications and Presentations

Despite long-standing interest of terrestrial ecologists, freshwater ecosystems are a fertile, yet unappreciated, testing ground for applying community phylogenetics to uncover mechanisms of species assembly. We quantify phylogenetic clustering and overdispersion of native and non-native fishes of a large river basin in the American Southwest to test for the mechanisms (environmental filtering versus competitive exclusion) and spatial scales influencing community structure. Contrary to expectations, non-native species were phylogenetically clustered and related to natural environmental conditions, whereas native species were not phylogenetically structured, likely reflecting human-related changes to the basin. The species that are most invasive (in terms of ecological impacts) …


Gently Clarifying The Application Of Horn’S Parallel Analysis To Principal Component Analysis Versus Factor Analysis, Alexis Dinno Jan 2014

Gently Clarifying The Application Of Horn’S Parallel Analysis To Principal Component Analysis Versus Factor Analysis, Alexis Dinno

Community Health Faculty Publications and Presentations

Horn’s parallel analysis (PA) is an empirical method used to decide how many components in a principal component analysis (PCA) or factors in a common factor analysis (CFA) drive the variance observed in a data set of n observations on p variables (Horn, 1965). This decision of how many components or factors to retain is critical in applications of PCA or CFA to reducing the dimensionality of data in analysis (as when compositing multiple scale items into a single score), and also in exploratory factor analysis where the different contributions of each factor to each observed variable help generate theory …


A Second Chance For Oregon, High School Dropouts, And The Ged, City Club Of Portland (Portland, Or.) Jan 2014

A Second Chance For Oregon, High School Dropouts, And The Ged, City Club Of Portland (Portland, Or.)

City Club of Portland

No abstract provided.


Effects Of Ethnicity And Gender On Sixth-Grade Students' Environmental Knowledge And Attitudes After Participation In A Year-Long Environmental Education Program, Rachel Stagner Jan 2014

Effects Of Ethnicity And Gender On Sixth-Grade Students' Environmental Knowledge And Attitudes After Participation In A Year-Long Environmental Education Program, Rachel Stagner

Dissertations and Theses

The goal of environmental education (EE) has always been to increase knowledge about the environment and to foster positive environmental attitudes. Increasingly, as the call for integrating EE programs into mainstream science curriculum intensifies, it is important to continue to evaluate the effectiveness of these programs not only through measures of change in knowledge and attitudes, but through the additional criteria of meeting the needs of different gender and ethnic groups.

The purpose of this research was to identify whether a watershed education program was meeting the needs of diverse learners within the context of a year-long, integrated, sixth-grade science …


"What Does This Graph Mean?" Formative Assessment With Science Inquiry To Improve Data Analysis, Andrea Dawn Leech Jan 2014

"What Does This Graph Mean?" Formative Assessment With Science Inquiry To Improve Data Analysis, Andrea Dawn Leech

Dissertations and Theses

This study investigated the use of formative assessment to improve three specific data analysis skills within the context of a high school chemistry class: graph interpretation, pattern recognition, and making conclusions based on data. Students need to be able to collect data, analyze that data, and produce accurate scientific explanations (NRC, 2011) if they want to be ready for college and careers after high school. This mixed methods study, performed in a high school chemistry classroom, investigated the impact of the formative assessment process on data analysis skills that require higher order thinking. We hypothesized that the use of evaluative …


Self-Efficacy In Low-Level English Language Learners, Laura F. Blumenthal Jan 2014

Self-Efficacy In Low-Level English Language Learners, Laura F. Blumenthal

Dissertations and Theses

Accounting for differences in second language proficiency attainment is an important area of inquiry in the study of Second Language Acquisition (SLA). Accounts of the language acquisition process have generally come from cognitive or psychological perspectives, which view language learning as primarily an internal mental/emotional process, or from sociocultural or critical perspectives that emphasize the influence of the learner's social environment. Research on variability in language learning has also failed to take into account the learning experiences of low-level learners.

This study adopted a social-psychological perspective on language acquisition that focused on the role of self-efficacy in learning, and applied …


Mobile Robot Localization Based On Kalman Filter, Omar Q. Mohsin Jan 2014

Mobile Robot Localization Based On Kalman Filter, Omar Q. Mohsin

Dissertations and Theses

Robot localization is one of the most important subjects in the Robotics science. It is an interesting and complicated topic. There are many algorithms to solve the problem of localization. Each localization system has its own set of features, and based on them, a solution will be chosen. In my thesis, I want to present a solution to find the best estimate for a robot position in certain space for which a map is available. The thesis started with an elementary introduction to the probability and the Gaussian theories. Simple and advanced practical examples are presented to illustrate each concept …


Managing For Resistance And Resilience Of Northern Great Lakes Forests To The Effects Of Climate Change, Matthew Joshua Duveneck Jan 2014

Managing For Resistance And Resilience Of Northern Great Lakes Forests To The Effects Of Climate Change, Matthew Joshua Duveneck

Dissertations and Theses

Climate change is expected to drastically change the environmental conditions which forests depend. Lags in tree species movements will likely be outpaced by a more rapidly changing climate. This may result in species extirpation, a change in forest structure, and a decline in resistance and resilience (i.e., the ability to persist and recover from external perturbations, respectively). In the northern Great Lakes region of North America, an ecotone exists along the boreal-temperate transition zone where large changes in species composition exist across a climate gradient. Increasing temperatures are observed in the more southern landscapes. As climate change is expected to …


Redefining Quality In Developing World Education, Kristi Jane Yuthas, Marc J. Epstein Jan 2014

Redefining Quality In Developing World Education, Kristi Jane Yuthas, Marc J. Epstein

Business Faculty Publications and Presentations

In the outskirts of Medellin, Colombia, impoverished rural schoolchildren have cause for hope. The Colombian Coffee Growers’ Association wants to hire them. Why? Because these children have developed the independent thinking, communication, and work skills that will make them an asset to the industry. They developed these skills in their multigrade primary schools, where children do most of their learning in competence-based groups, while the teacher functions as guide and coach.

In Kenya, a teenage boy is also celebrating. A primary school dropout who once survived outside the law, he now runs his own small business, lives on his own, …


Towards Improving Drought Forecasts Across Different Spatial And Temporal Scales, Shahrbanou Madadgar Jan 2014

Towards Improving Drought Forecasts Across Different Spatial And Temporal Scales, Shahrbanou Madadgar

Dissertations and Theses

Recent water scarcities across the southwestern U.S. with severe effects on the living environment inspire the development of new methodologies to achieve reliable drought forecasting in seasonal scale. Reliable forecast of hydrologic variables, in general, is a preliminary requirement for appropriate planning of water resources and developing effective allocation policies. This study aims at developing new techniques with specific probabilistic features to improve the reliability of hydrologic forecasts, particularly the drought forecasts. The drought status in the future is determined by certain hydrologic variables that are basically estimated by the hydrologic models with rather simple to complex structures. Since the …


Central Cascadia Subduction Zone Creep, Gina M. Schmalzle, Robert Mccaffrey, Kenneth C. Creager Jan 2014

Central Cascadia Subduction Zone Creep, Gina M. Schmalzle, Robert Mccaffrey, Kenneth C. Creager

Geology Faculty Publications and Presentations

Central Cascadia between 43ºN and 46ºN has reduced interseismic uplift observed in geodetic data and coseismic subsidence seen in multiple thrust earthquakes, suggesting elevated persistent fault creep in this section of the subduction zone. We estimate subduction thrust "decade-scale" locking and crustal block rotations from three-component continuous Global Positioning System (GPS) time series from 1997 to 2013, as well as 80 year tide gauge and leveling-derived uplift rates. Geodetic observations indicatecoastal central Oregon is rising at a slower rate than coastal Washington, southern Oregon and northern California. Modeled locking distributions suggest a wide locking transition zone that extends inland undercentral …


3d Printing Of Crystallographic Models And Open Access Databases, Werner Kaminsky, Trevor J. Snyder, Peter Moeck Jan 2014

3d Printing Of Crystallographic Models And Open Access Databases, Werner Kaminsky, Trevor J. Snyder, Peter Moeck

Physics Faculty Publications and Presentations

Provides a brief overview of opportunities for crystallography allowed by the recent developments in 3D printing technology. in combination with open access databases.


Reliability Analysis For Chain Topology Wireless Sensor Networks With Multiple-Sending Transmission Scheme, Jie Cai, Xiaoyu Song, Jinyuan Wang, Ming Gu Jan 2014

Reliability Analysis For Chain Topology Wireless Sensor Networks With Multiple-Sending Transmission Scheme, Jie Cai, Xiaoyu Song, Jinyuan Wang, Ming Gu

Electrical and Computer Engineering Faculty Publications and Presentations

Reliability analysis is a key problem in wireless sensor networks (WSNs). The primary contribution of this paper is an in-depth study of the reliability of a chain topology wireless sensor network with multiple-sending scheme. We study the wireless link reliability for the fading channels. The node energy availability for the source and relay nodes is investigated in terms of the limited node energy. The instantaneous network reliability and the mean time to failure are derived. Finally, the initial node energy allocation scheme is proposed to balance the lifetime of each sensor node, thus reducing the total energy consumption. The simulation …


Curriculum Change 2014-2015, Portland State University Jan 2014

Curriculum Change 2014-2015, Portland State University

Bulletin & Curriculum Change Documents

No abstract provided.


Bulletin: General Catalog Issue 2014-2015, Portland State University Jan 2014

Bulletin: General Catalog Issue 2014-2015, Portland State University

Bulletin & Curriculum Change Documents

No abstract provided.


Modeling Effective Shade To Prioritize Riparian Restoration Efforts In The Johnson Creek Watershed, Or, Brittany Sahatjian Jan 2014

Modeling Effective Shade To Prioritize Riparian Restoration Efforts In The Johnson Creek Watershed, Or, Brittany Sahatjian

Environmental Science and Management Professional Master's Project Reports

The influence of stream temperature on the survival and reproductive success of anadromous salmonid populations has become an increasingly concerning issue in the Pacific Northwest. Enhancing the height, density and extent of riparian vegetation is widely accepted as one of the most effective strategies for reducing stream temperatures, while also providing numerous ancillary benefits. Effective shade is defined as the percentage of direct beam solar radiation attenuated and scattered by riparian vegetation before reaching the stream surface and is a commonly used criterion for choosing where to restore riparian vegetation. This project aims to prioritize sites for riparian restoration through …


Getting Your House In Order: A Model For African-American Financial Education, Lisa K. Bates, Stacey Triplett Jan 2014

Getting Your House In Order: A Model For African-American Financial Education, Lisa K. Bates, Stacey Triplett

Urban Studies and Planning Faculty Publications and Presentations

The Portland Housing Center (PHC) is a national leader in educating and creating first time homebuyers, with outreach efforts that bring diverse households to its services. However, in 2010, PHC recognized that African American customers were much less likely to buy homes, even when they received counseling. The Portland (OR) area’s African American homeownership rate was just 35% (compared to 65% for Whites) and actually declined from 2000 to 2010.

Working with an African American advisory committee and with research guiding development, implementation, and evaluation, PHC developed a comprehensive program around outreach and services to African Americans in the Portland …


Functional Verification Of High Performance Adders In Coq, Qian Wang, Xiaoyu Song, Ming Gu, Jiaguang Sun Jan 2014

Functional Verification Of High Performance Adders In Coq, Qian Wang, Xiaoyu Song, Ming Gu, Jiaguang Sun

Electrical and Computer Engineering Faculty Publications and Presentations

Addition arithmetic design plays a crucial role in high performance digital systems. The paper proposes a systematic method to formalize and verify adders in a formal proof assistant COQ. The proposed approach succeeds in formalizing the gate-level implementations and verifying the functional correctness of the most important adders of interest in industry, in a faithful, scalable, and modularized way. The methodology can be extended to other adder architectures as well.


Cost Minimization Approach To Synthesis Of Linear Reversible Circuits, Ben Schaeffer, Marek Perkowski Jan 2014

Cost Minimization Approach To Synthesis Of Linear Reversible Circuits, Ben Schaeffer, Marek Perkowski

Electrical and Computer Engineering Faculty Publications and Presentations

This paper presents a heuristic cost minimization approach to synthesizing linear reversible circuits. Two bidirectional linear reversible circuit synthesis methods are introduced, the Alternating Elimination with Cost Minimization method (AECM) and the Multiple CNOT Gate method (MCG). Algorithms, example syntheses, and extensions to these methods are presented. An MCG variant which incorporates line reordering is introduced. Tests comparing the new cost minimization methods with the best known method for large circuits are presented. Results show that of the three methods MCG had the lowest average CNOT gate counts for linear reversible circuits up to 24 lines, and that AECM had …


Wider Dissemination Of Household Travel Survey Data Using Geographical Perturbation Methods, Kelly J. Clifton, Steven R. Gehrke Jan 2014

Wider Dissemination Of Household Travel Survey Data Using Geographical Perturbation Methods, Kelly J. Clifton, Steven R. Gehrke

Civil and Environmental Engineering Faculty Publications and Presentations

Public agencies spend vast amounts of money collecting information about passenger travel in household travel surveys. These data are valuable for the rich and detailed information they provide, which contribute to regional and statewide travel demand models. These data have utility beyond travel demand modeling in their application to transportation policy and travel behavior research. As the demand on these data increase, so have the quantity of information collected. Detailed geospatial referencing of the home, work and other travel destinations are common practice and permit the integration with other spatially archived data sources, such as land use characteristics, transportation system …


3d Printing & Open Access Databases For Crystallographic College Education, Peter Moeck, Jennifer Stone-Sundberg, Trevor J. Snyder, Werner Kaminsky, Saulius Grazulis, International Advisory Board Of The Crystallography Open Database Jan 2014

3d Printing & Open Access Databases For Crystallographic College Education, Peter Moeck, Jennifer Stone-Sundberg, Trevor J. Snyder, Werner Kaminsky, Saulius Grazulis, International Advisory Board Of The Crystallography Open Database

Physics Faculty Publications and Presentations

Presentation gives an overview of available open access databases of crystals and crystal structures, as well as discussions of how newly developed 3D printing technologies can be used to teach crystallography at the college level. Offers advice regarding conversion of crystallographic information files to 3D printing files, and shares news from the 3D printing of crystallographic models community.