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The Effect Of Channel Deepening On Tides And Storm Surge: A Case Study Of Wilmington, Nc, R. Familkhalili, Stefan A. Talke Jan 2016

The Effect Of Channel Deepening On Tides And Storm Surge: A Case Study Of Wilmington, Nc, R. Familkhalili, Stefan A. Talke

Civil and Environmental Engineering Faculty Publications and Presentations

In this study we investigate the hypothesis that increasing channel depth in estuaries can amplify both tides and storm surge by developing an idealized numerical model representing the 1888, 1975, and 2015 bathymetric conditions of the Cape Fear River Estuary, NC. Archival tide gauge data recovered from the U.S. National Archives indicates that mean tidal range in Wilmington has doubled to 1.55m since the 1880s, with a much smaller increase of 0.07mobserved near the ocean boundary. These tidal changes are reproduced by simulating channel depths of 7m (1888 condition) and 15.5m (modern condition). Similarly, model sensitivity studies using idealized, parametric …

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Model Lessons For Math And Geography Activities, Karen Adams, Tyler Sexton, Shawnti Peachey Jan 2016

Model Lessons For Math And Geography Activities, Karen Adams, Tyler Sexton, Shawnti Peachey

Instructional Materials

Model Lessons for Math and Geography Activities to use with The Student Atlas of Oregon.

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The Nature Of Kinematic Waves In Glaciers And Their Application To Understanding The Nisqually Glacier, Mt. Rainier, Washington, Brita Ilyse Horlings Jan 2016

The Nature Of Kinematic Waves In Glaciers And Their Application To Understanding The Nisqually Glacier, Mt. Rainier, Washington, Brita Ilyse Horlings

University Honors Theses

The Nisqually Glacier is one of the best studied glaciers on Mt. Rainier. Data was first collected on the glacier in 1857 and since then a number of kinematic waves have been observed but not extensively studied. The purpose of the thesis is to numerically model the conditions that favor or restrict kinematic wave propagation/initiation and subsequently model the relationship between kinematic wave behavior and the Nisqually Glacier. The numerical models used in this study are 2-D and use bedrock elevation, mass balance, basal sliding, and other equations to simulate alpine glaciers. A perturbation is added instantaneously for a specified …

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Atmospheric Methane Isotopic Record Favors Fossil Sources Flat In 1980s And 1990s With Recent Increase, Andrew L. Rice, Christopher Butenhoff, Doaa Galal Mohammed Teama, Florian H. Roger, M. A. K. Khalil, R. A. Rasmussen Jan 2016

Atmospheric Methane Isotopic Record Favors Fossil Sources Flat In 1980s And 1990s With Recent Increase, Andrew L. Rice, Christopher Butenhoff, Doaa Galal Mohammed Teama, Florian H. Roger, M. A. K. Khalil, R. A. Rasmussen

Physics Faculty Publications and Presentations

Observations of atmospheric methane (CH4) since the late 1970s and measurements of CH4 trapped in ice and snow reveal a meteoric rise in concentration during much of the twentieth century. Since 1750, levels of atmospheric CH4 have more than doubled to current globally averaged concentration near 1,800 ppb. During the late 1980s and 1990s, the CH4 growth rate slowed substantially and was near or at zero between 1999 and 2006. There is no scientific consensus on the drivers of this slowdown. Here, we report measurements of the stable isotopic composition of atmospheric CH4 (13C/12C and D/H) from a rare air …

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Adjustment To College In The United States: Perceptions Of Qatari Students, Janet S. Walker, Jennifer E. Blakeslee, Batoul Khalifa, Ramzi Nasser, Atmane Ikhlef Jan 2016

Adjustment To College In The United States: Perceptions Of Qatari Students, Janet S. Walker, Jennifer E. Blakeslee, Batoul Khalifa, Ramzi Nasser, Atmane Ikhlef

School of Social Work Faculty Publications and Presentations

This qualitative study is part of a collaborative research effort undertaken by investigators based in the United States and Qatar to better understand Qatari student perspectives on their post-secondary adjustment and success. Here, we report findings from structured interviews with Qatari nationals studying abroad in the US, all of whom were males who were, or had recently been, undergraduates at state universities and/or community colleges in Oregon (n=21). Approximately two-thirds were in business or economics programs and about a third in STEM programs (science, technology, engineering, or mathematics). Most of the interviews were conducted in Arabic and translated into English …

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3d Fpga Cell Matrix By Self-Assembly, Jeffrey Udall Jan 2016

3d Fpga Cell Matrix By Self-Assembly, Jeffrey Udall

Maseeh Summer Undergraduate Research Experience

Physical size limitations in miniaturizing two-dimensional (2D) transistors are becoming more difficult to overcome. In order to continue increasing the processing power of electronic circuits, new design paradigms are needed. Three-dimensional (3D) architectures provide a solution to this issue and are currently being implemented via wafer stacking. However, more significant gains in terms of packing and speed can be achieved by CMOS components with truly integrated 3D cellular architectures. One of these is the Cell Matrix, a self-configurable defect- and fault-tolerant architecture, which is ideally suited for ultra large-scale integration. For this project, we worked to expand the Cell Matrix …

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Complex Capillary Fluidic Phenomena For Passive Control Of Liquids In Low-Gravity Environments, Logan Torres Jan 2016

Complex Capillary Fluidic Phenomena For Passive Control Of Liquids In Low-Gravity Environments, Logan Torres

Maseeh Summer Undergraduate Research Experience

In an effort to further apply the recent results of puddle jumping research, we seek to expand the oblique droplet impact studies of others by exploiting large liquid droplets in the near weightless environment of a drop tower. By using the spontaneous puddle jump mechanism, droplets of volumes 1 mL ≤ V ≤ 3 mL with corresponding Weber numbers of We ≈ 1 are impinged on surfaces inclined in the range 40° ≤ α ≤ 80° (measured from the horizontal plane). Impact surface wetting characteristics exhibit static contact angles θstatic = 165 ± 5°. All impacts result in complete rebound. …

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Oxyhalogen-Sulfur Chemistry: Kinetics And Mechanism Of Oxidation Of N-Acetylthiourea By Aqueous Bromate And Acidified Bromate, Kudzanai Chipiso, Wilbes Mbiya, Thai Tran, Reuben H. Simoyi Jan 2016

Oxyhalogen-Sulfur Chemistry: Kinetics And Mechanism Of Oxidation Of N-Acetylthiourea By Aqueous Bromate And Acidified Bromate, Kudzanai Chipiso, Wilbes Mbiya, Thai Tran, Reuben H. Simoyi

Chemistry Faculty Publications and Presentations

The oxidation of N-acetylthiourea (ACTU) by acidic bromate has been studied by observing formation of bromine in excess bromate conditions. The reaction displays an induction period before formation of bromine. The stoichiometry of the reaction was determined to be 4:3: 4BrO 3 – +3(CH 3 CO)NH(NH 2 )C=S+3H 2 O®4Br – +3(CH 3 CO)NH(NH 2 )C=O+3SO 4 2– +6H + (A) with a complete desulfurization of ACTU to its urea analogue. In excess bromate conditions the stoichiometry was 8:5: 8BrO 3 – + 5(CH 3 CO)NH(NH 2 )C=S + H 2 O ® 4Br 2 + 5(CH 3 CO)NH(NH 2 …

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Electrochemistry-Coupled To Mass Spectrometry In Simulation Of Metabolic Oxidation Of Methimazole: Identification And Characterization Of Metabolites, Kudzanai Chipiso, Reuben H. Simoyi Jan 2016

Electrochemistry-Coupled To Mass Spectrometry In Simulation Of Metabolic Oxidation Of Methimazole: Identification And Characterization Of Metabolites, Kudzanai Chipiso, Reuben H. Simoyi

Chemistry Faculty Publications and Presentations

Methimazole (MMI), an antithyroid drug, is associated with idiosyncratic toxicity. Reactive metabolites resulting from bioactivation of the drug have been implicated in these adverse drug reactions. Mimicry of enzymatic oxidation of MMI was carried out by electrochemically oxidizing MMI using a coulometric flow-through cell equipped with a porous graphite working electrode. The cell was coupled on-line to electrospray ionization mass spectrometry (EC/ESI-MS). ESI spectra were acquired in both negative and positive modes. In acidic medium, ESI spectral analysis showed that the dimer was the main product, while in neutral and basic media, methimazole sulfenic acid, methimazole sulfinic acid and methimazole …

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Autism, Tara Crapnell, Lynette Lau, Christopher D. Hanks, Christina Nicolaidis, Alice Kuo Jan 2016

Autism, Tara Crapnell, Lynette Lau, Christopher D. Hanks, Christina Nicolaidis, Alice Kuo

School of Social Work Faculty Publications and Presentations

Autism spectrum disorder (ASD) is a complex, lifelong neurodevelopmental condition that is marked by deficits in social communication and interaction, and repetitive or restrictive patterns of behavior, interests, or activities. These symptoms can create challenges for individuals on the autism spectrum and their parents during the transition to adulthood, which may interfere with their ability to access and receive adequate and appropriate health care. Awareness of how the challenges associated with ASD may translate to healthcare barriers can help primary care providers address the complex needs of individuals who are on the autism spectrum and mitigate the risks of additional …

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Full State Revivals In Linearly Coupled Chains With Commensurate Eigenspectra, J. J. P. Veerman, Jovan Petrovic Jan 2016

Full State Revivals In Linearly Coupled Chains With Commensurate Eigenspectra, J. J. P. Veerman, Jovan Petrovic

Mathematics and Statistics Faculty Publications and Presentations

Coherent state transfer is an important requirement in the construction of quantum computer hardware. The state transfer can be realized by linear next-neighbour-coupled finite chains. Starting from the commensurability of chain eigenvalues as the general condition of periodic dynamics, we find chains that support full periodic state revivals. For short chains, exact solutions are found analytically by solving the inverse eigenvalue problem to obtain the coupling coefficients between chain elements. We apply the solutions to design optical waveguide arrays and perform numerical simulations of light propagation thorough realistic waveguide structures. Applications of the presented method to the realization of a …

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Associations Between Performance On An Abbreviated Cogstate Battery, Other Measures Of Cognitive Function, And Biomarkers In People At Risk For Alzheimer's Disease, Annie M. Racine, Lindsay R. Clark, Sara C. Berman, Rebecca L. Koscik, Kimberly D. Mueller, Derek Norton, Christopher R. Nicholas, Kaj Blennow, Henrik Zetterberg, Bruno M. Jedynak, Murat Bilgel, Cynthia M. Carlsson, Bradley T. Christian, Sanjay Asthana, Sterling C. Johnson Jan 2016

Associations Between Performance On An Abbreviated Cogstate Battery, Other Measures Of Cognitive Function, And Biomarkers In People At Risk For Alzheimer's Disease, Annie M. Racine, Lindsay R. Clark, Sara C. Berman, Rebecca L. Koscik, Kimberly D. Mueller, Derek Norton, Christopher R. Nicholas, Kaj Blennow, Henrik Zetterberg, Bruno M. Jedynak, Murat Bilgel, Cynthia M. Carlsson, Bradley T. Christian, Sanjay Asthana, Sterling C. Johnson

Mathematics and Statistics Faculty Publications and Presentations

It is not known whether computerized cognitive assessments, like the CogState battery, are sensitive to preclinical cognitive changes or pathology in people at risk for Alzheimer's disease(AD). In 469 late middle-aged participants from the Wisconsin Registry for Alzheimer's Prevention(mean age 63.8±7 years at testing; 67% female; 39% APOE4+), we examined relationships between a CogState abbreviated battery(CAB) of seven tests and demographic characteristics, traditional paper-based neuropsychological tests as well as a composite cognitive impairment index, cognitive impairment status(determined by consensus review), and biomarkers for amyloid and tau(CSF phosphorylated-tau/Aβ42 and global PET-PiB burden) and neural injury(CSF neurofilament light protein). CSF and PET-PiB …

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Voxel Based Morphometry In Optical Coherence Tomography: Validation & Core Findings, Bhavna J. Antony, Min Chen, Aaron Carass, Bruno M. Jedynak, Omar Al-Louzi, Sharon D. Solomon, Shiv Saidha, Peter Calabresi, Jerry L. Prince Jan 2016

Voxel Based Morphometry In Optical Coherence Tomography: Validation & Core Findings, Bhavna J. Antony, Min Chen, Aaron Carass, Bruno M. Jedynak, Omar Al-Louzi, Sharon D. Solomon, Shiv Saidha, Peter Calabresi, Jerry L. Prince

Mathematics and Statistics Faculty Publications and Presentations

Optical coherence tomography (OCT) of the human retina is now becoming established as an important modality for the detection and tracking of various ocular diseases. Voxel based morphometry (VBM) is a long standing neuroimaging analysis technique that allows for the exploration of the regional differences in the brain. There has been limited work done in developing registration based methods for OCT, which has hampered the advancement of VBM analyses in OCT based population studies. Following on from our recent development of an OCT registration method, we explore the potential benefits of VBM analysis in cohorts of healthy controls (HCs) and …

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Teacher Noticing Of Justification: Attending To The Complexity Of Mathematical Content And Practice, Kathleen Mary Melhuish, Eva Thanheiser, Jodi I. Fasteen, Julie Fredericks Jan 2016

Teacher Noticing Of Justification: Attending To The Complexity Of Mathematical Content And Practice, Kathleen Mary Melhuish, Eva Thanheiser, Jodi I. Fasteen, Julie Fredericks

Mathematics and Statistics Faculty Publications and Presentations

In this report, we will consider in-service elementary school teachers' noticing of the mathematical practice: justification. This study is part of a larger project evaluating the efficacy of a three year professional development built around attending to student thinking and promoting mathematical habits of justifying, generalizing and making sense. Noticing just¢cation is a complex task requiring attention to both the (1) mathematical content and strategies and (2) the nature of the argument provided by a student. We have found that teachers' struggle to attend to both aspects simultaneously and offer a framework for considering teacher noticing of mathematical practices.

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The Language Of Professional Development Leaders, Andrew Riffel, Kathleen Mary Melhuish, Eva Thanheiser Jan 2016

The Language Of Professional Development Leaders, Andrew Riffel, Kathleen Mary Melhuish, Eva Thanheiser

Mathematics and Statistics Faculty Publications and Presentations

Leaders in professional development (PD) initiatives (such as facilitators, principals, coaches) hold a great deal of power in their language, carrying the ability to manage meaning and frame experiences. Rather than working from interview data, this report addresses a gap in leadership research by examining the words used by leaders in their on-the-job interactions. We present an initial framework for capturing leadership language qualities at the macro level (framing the PD’s purpose) and micro level (rhetorical crafting in terms of metaphor usage, pronoun choice, and other language selections). Our data come from a larger project evaluating the efficacy of a …

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Landmark Based Shape Analysis For Cerebellar Ataxia Classification And Cerebellar Atrophy Pattern Visualization, Zhen Yang, S. Mazdak Abulnaga, Aaron Carass, Bruno Jedynak, Chiadi U. Onyike, Jerry L. Prince, Multiple Additional Authors Jan 2016

Landmark Based Shape Analysis For Cerebellar Ataxia Classification And Cerebellar Atrophy Pattern Visualization, Zhen Yang, S. Mazdak Abulnaga, Aaron Carass, Bruno Jedynak, Chiadi U. Onyike, Jerry L. Prince, Multiple Additional Authors

Mathematics and Statistics Faculty Publications and Presentations

Cerebellar dysfunction can lead to a wide range of movement disorders. Studying the cerebellar atrophy pattern associated with different cerebellar disease types can potentially help in diagnosis, prognosis, and treatment planning. In this paper, we present a landmark based shape analysis pipeline to classify healthy control and different ataxia types and to visualize the characteristic cerebellar atrophy patterns associated with different types. A highly informative feature representation of the cerebellar structure is constructed by extracting dense homologous landmarks on the boundary surfaces of cerebellar sub-structures. A diagnosis group classifier based on this representation is built using partial least square dimension …

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The Conflict Resolution Case Study In Urban Life: Bull Run Watershed Case, Chang-Yu Hong Jan 2016

The Conflict Resolution Case Study In Urban Life: Bull Run Watershed Case, Chang-Yu Hong

Geography Faculty Publications and Presentations

The City of Portland and the United States Department of Agriculture (USDA) Forest Service are working together, along with citizens, to formulate a comprehensive new policy to guide joint management of the Bull Run watershed at Mt. Hood National Forest. This process has brought about four decades of conflict, resulting from differences between the federal view of multiple use and the local view of exclusive use for producing high quality water. The new policy is being formulated by the City of Portland and the Forest Service through negotiation of a comprehensive Memorandum of Understanding that structures the parties’ roles, responsibilities, …

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A Method For Achieving Analytic Formulas For Three Body Integrals Consisting Of Powers And Exponentials In All Three Interparticle Hyllerass Coordinates, Chris M. Keating Dec 2015

A Method For Achieving Analytic Formulas For Three Body Integrals Consisting Of Powers And Exponentials In All Three Interparticle Hyllerass Coordinates, Chris M. Keating

Dissertations and Theses

After an introduction to the variational principle of three body systems via the Helium atom, we present general analytical formulas for the radial parts of integrals that occur when three body systems are described using wave functions that consist of powers and exponentials in all three interparticle Hylleraas coordinates [Hylleraas1929]. This work is an extension of integrals given by Harris, Frolov and Smith, Jr. [Harris2004]. Specifically included are radial integrals encountered in calculations involving the dipole moment matrix element in Hylleraas coordinates that contain a function f(kr1) (such as a spherical Bessel function) in addition to …

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Debris Flow Susceptibility Map For Mount Rainier, Washington Based On Debris Flow Initiation Zone Characteristics From The November, 2006 Climate Event In The Cascade Mountains, Kassandra Lindsey Dec 2015

Debris Flow Susceptibility Map For Mount Rainier, Washington Based On Debris Flow Initiation Zone Characteristics From The November, 2006 Climate Event In The Cascade Mountains, Kassandra Lindsey

Dissertations and Theses

In November 2006 a Pineapple Express rainstorm moved through the Pacific Northwest generating record precipitation, 22 to 50 cm in the two-day event on Mt. Rainier. Copeland (2009) and Legg (2013) identified debris flows in seven drainages in 2006; Inter Fork, Kautz, Ohanapecosh, Pyramid, Tahoma, Van Trump, and West Fork of the White River. This study identified seven more drainages: Carbon, Fryingpan, Muddy Fork Cowlitz, North Puyallup, South Mowich, South Puyallup, and White Rivers. Twenty-nine characteristics, or attributes, associated with the drainages around the mountain were collected. Thirteen were used in a regression analysis in order to develop a susceptibility …

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Dendrochronology And Middle Miocene Petrified Oak: Modern Counterparts And Interpretation, William E. Wright, Martin J. Streck, Christopher Baisan, W. Walton Wright, Paul Szejner Dec 2015

Dendrochronology And Middle Miocene Petrified Oak: Modern Counterparts And Interpretation, William E. Wright, Martin J. Streck, Christopher Baisan, W. Walton Wright, Paul Szejner

Geology Faculty Publications and Presentations

This study reports the first successful statistical crossdating among many ring width time series from petrified wood, thus providing a replicable continuous annual resolution window into tree growth and environmental influences during the middle Miocene. The petrified samples, of the genus Quercus, originated at the Stinking Water (SW) locality in Oregon, a Miocene-aged exposure associated with the Columbia River Basalts. 40AR/39AR dating on pillow basalt from the locality yielded a weighted Plateau Age of 13.79 ±0.09 Ma placing the death of the trees at the end of the Langhian Stage of the Middle Miocene (15.97±0.05 to 13.65±0.05 …

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Analysis Of Capillary Flow In Interior Corners : Perturbed Power Law Similarity Solutions, Joshua Thomas Mccraney Dec 2015

Analysis Of Capillary Flow In Interior Corners : Perturbed Power Law Similarity Solutions, Joshua Thomas Mccraney

Dissertations and Theses

The design of fluid management systems requires accurate models for fluid transport. In the low gravity environment of space, gravity no longer dominates fluid displacement; instead capillary forces often govern flow. This thesis considers the redistribution of fluid along an interior corner. Following a rapid reduction of gravity, fluid advances along the corner measured by the column length z = L(t), which is governed by a nonlinear partial differential equation with dynamical boundary conditions. Three flow types are examined: capillary rise, spreading drop, and tapered corner. The spreading drop regime is shown to exhibit column length growth L ~ …

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The Effects Of An Overnight Environmental Science Education Program On Students' Attendance Rate Change For Middle School Years, Jennifer Elizabeth Basham Dec 2015

The Effects Of An Overnight Environmental Science Education Program On Students' Attendance Rate Change For Middle School Years, Jennifer Elizabeth Basham

Dissertations and Theses

Programs that engage middle students in participatory, real-world, and hands-on field based instruction can be a powerful asset to the educational experiences for students; motivating and inspiring some to appreciate and value school in a different way. Overnight environmental science programs have a unique opportunity to support students by creating experiences where students can participate in learning in vastly different ways from what they may engage with in the traditional 4-walled classroom, while concurrently developing a relationship with the natural world. Decreasing educational budgets and increased need to substantiate educational programs in terms of their impact on students has added …

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From Boolean Equalities To Constraints, Sergio Antoy, Michael Hanus Dec 2015

From Boolean Equalities To Constraints, Sergio Antoy, Michael Hanus

Computer Science Faculty Publications and Presentations

Although functional as well as logic languages use equality to discriminate between logically different cases, the operational meaning of equality is different in such languages. Functional languages reduce equational expressions to their Boolean values, True or False, logic languages use unification to check the validity only and fail otherwise. Consequently, the language Curry, which amalgamates functional and logic programming features, offers two kinds of equational expressions so that the programmer has to distinguish between these uses. We show that this distinction can be avoided by providing an analysis and transformation method that automatically selects the appropriate operation. Without this distinction …

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Quaternary Chronology And Stratigraphy Of Mickey Springs, Oregon, Leslie Allen Mowbray Dec 2015

Quaternary Chronology And Stratigraphy Of Mickey Springs, Oregon, Leslie Allen Mowbray

Dissertations and Theses

Mickey Springs in the Alvord Desert, southeast Oregon, is analogous to other Basin and Range hydrothermal systems where the requisite conditions of heat source and permeable pathways are met through crustal thinning due to normal faulting. This study examines the morphology and lifespan of near-surface spring features through use of ground penetrating radar, thermoluminescence (TL) dating, and elevation modeling. Duration of hydrothermal activity at Mickey Springs has not previously been determined, and age determinations of sinter at the site are conflicting. The reason for and timing of this change in silica saturation in the hydrothermal fluid has not been resolved. …

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Engineering A Healthier Watershed: Middle School Students Use Engineering Design To Lessen The Impact Of Their Campus' Impervious Surfaces On Their Local Watershed, Elizabeth Claire Gardner Dec 2015

Engineering A Healthier Watershed: Middle School Students Use Engineering Design To Lessen The Impact Of Their Campus' Impervious Surfaces On Their Local Watershed, Elizabeth Claire Gardner

Dissertations and Theses

It is important that students understand not only how their local watershed functions, but also how it is being impacted by impervious surfaces. Additionally, students need experience exploring the scientific and engineering practices that are necessary for a strong STEM background. With this knowledge students can be empowered to tackle this real and local problem using engineering design, a powerful practice gaining momentum and clarity through its prominence in the recent Framework for K-12 Science Education. Twenty classes of suburban sixth-graders participated in a new five-week Watershed Engineering Design Unit taught by their regular science teachers. Students engaged in scientific …

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Isn’T Citizen Science A Hoot? A Case-Study Exploring The Effectiveness Of Citizen Science As An Instrument To Teach The Nature Of Science Through A Local Nocturnal Owl-Monitoring Project, Tess Marie Kreofsky Dec 2015

Isn’T Citizen Science A Hoot? A Case-Study Exploring The Effectiveness Of Citizen Science As An Instrument To Teach The Nature Of Science Through A Local Nocturnal Owl-Monitoring Project, Tess Marie Kreofsky

Dissertations and Theses

Citizen science projects present a distinctive opportunity for professional and volunteer scientists to coordinate their efforts to gather unique sets of data that can benefit the scientific and local communities. These projects are assumed to be an effective educational tool to teach nature of science (NOS) to participants (Brossard, Lewenstein, Bonney, 2005). This case study evaluates the effectiveness of participation in a citizen science project as a way to learn about NOS. Through enhancement of the Tryon Creek Owl Monitoring Project the researcher reviewed the characteristics of a citizen science project that were thought to be necessary to impact the …

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The Performance Of Random Prototypes In Hierarchical Models Of Vision, Kendall Lee Stewart Dec 2015

The Performance Of Random Prototypes In Hierarchical Models Of Vision, Kendall Lee Stewart

Dissertations and Theses

I investigate properties of HMAX, a computational model of hierarchical processing in the primate visual cortex. High-level cortical neurons have been shown to respond highly to particular natural shapes, such as faces. HMAX models this property with a dictionary of natural shapes, called prototypes, that respond to the presence of those shapes. The resulting set of similarity measurements is an effective descriptor for classifying images. Curiously, prior work has shown that replacing the dictionary of natural shapes with entirely random prototypes has little impact on classification performance. This work explores that phenomenon by studying the performance of random prototypes on …

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Next-Generation Scientists Get A Taste Of Their Future Careers, Patrick M. Edwards, Linda A. George, Matthew Mctammany Dec 2015

Next-Generation Scientists Get A Taste Of Their Future Careers, Patrick M. Edwards, Linda A. George, Matthew Mctammany

Environmental Science and Management Faculty Publications and Presentations

Article provides an overview of the middle and high school poster session that took place during the 2014 Joint Aquatic Sciences Meeting (JASM) in Portland, Oregon. The poster session provided the students with opportunity to participate in the research process and prepare their posters.

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Advances In Autonomous-Underwater-Vehicle Based Passive Bottom-Loss Estimation By Processing Of Marine Ambient Noise, Lanfranco Muzi Dec 2015

Advances In Autonomous-Underwater-Vehicle Based Passive Bottom-Loss Estimation By Processing Of Marine Ambient Noise, Lanfranco Muzi

Dissertations and Theses

Accurate modeling of acoustic propagation in the ocean waveguide is important to SONAR-performance prediction, and requires, particularly in shallow water environments, characterizing the bottom reflection loss with a precision that databank-based modeling cannot achieve. Recent advances in the technology of autonomous underwater vehicles (AUV) make it possible to envision a survey system for seabed characterization composed of a short array mounted on a small AUV. The bottom power reflection coefficient (and the related reflection loss) can be estimated passively by beamforming the naturally occurring marine ambient-noise acoustic field recorded by a vertical line array of hydrophones. However, the reduced array …

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The Biology Of Eastern Kingbirds At Malheur National Wildlife Refuge: Survival, Reproduction, And Testosterone Secretion, Lucas J. Redmond Dec 2015

The Biology Of Eastern Kingbirds At Malheur National Wildlife Refuge: Survival, Reproduction, And Testosterone Secretion, Lucas J. Redmond

Dissertations and Theses

This dissertation presents the results of a study that I undertook to better understand the breeding biology of Eastern Kingbirds (hereafter, kingbirds) at Malheur National Wildlife Refuge in southeastern Oregon from 2003 to 2009. Kingbirds are long-distance migratory songbirds that breed across much of North America. This species is socially monogamous but, via frequent extra-pair copulations, is genetically polygamous. Kingbirds exhibit relatively high breeding site fidelity, often returning to the same tree to nest in subsequent years. Both members of a pair provide parental care, but there are often specific duties performed by both male and female kingbirds. For example, …

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