Physical Sciences and Mathematics Commons^™

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 …

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 …

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 ~ …

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. …

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 …

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 …

Polymeric Porphyrins As Solar Photocatalysts, Nicholas Upton Day

Dissertations and Theses

Research concentrated on the absorption, transformation, and storage of light energy is useful for the energy challenges faced by humanity. In particular, photocatalysis using solar energy to generate useful fuels has become a primary research goal in the drive to replace fossil fuels for the future. In this dissertation it is shown that poly-tetra(4-aminophenyl)porphyrin (pTAPP) can be oxidatively polymerized using a variety of methods, including electropolymerization, chemical oxidation, and interfacial polymerization and that pTAPP has photocatalytic ability to reduce O₂ to H₂O₂ for a storable fuel.

Organic conductive polymers such as pTAPP are attractive catalysts because …

Design And Synthesis Of Novel Chloroquine-Based Antimalarials, Kevin Vincent Murphy

Dissertations and Theses

Malaria is an infectious, often fatal disease that afflicts nearly 200 million people every year. The disease, characterized by recurring and extreme flu-like symptoms, is caused by the protozoan parasite Plasmodium falciparum. Victims usually contract the disease through a mosquito vector. Chloroquine is a chemotherapeutic that was introduced in the 1940s. For many years the drug was the foremost treatment of malaria, being effective and producing few side effects. Unfortunately, tolerance to chloroquine developed when the parasite evolved a resistance mechanism. Newer drugs have been developed and implemented, but these medicines also show a decreasing effect with continued administration. …

Effects Of Aerial Exposure On Preservation Of Low-Temperature Calothrix Biosignatures In Silica Sinter From Queen's Laundry, Yellowstone National Park, Usa, Shana Kendall

Dissertations and Theses

Mineral-depositing hydrothermal ecosystems, such as the hot springs in Yellowstone National Park, provide an unparalleled opportunity to document how microbial biosignatures form and contribute to the body of evidence indicative of the microbial inhabitants of active hot springs. Mineralization of microbial communities in silica-depositing hot springs can result in the preservation of microbial biofacies in the geologic record. To determine the effects of prolonged aerial exposure on the preservation potential of mid-to-low temperature cyanobacteria dominated microbial communities that are typically permineralized in the siliceous sinter, modern biofacies samples of such communities were collected from the active and inactive parts of …

Does Gender Matter? Human Elephant Conflict In Sri Lanka: A Gendered Analysis Of Human Elephant Conflict And Natural Resource Management In A Rural Sri Lankan Village, Katherine Eileen Griffin

Dissertations and Theses

This study is a gendered analysis of natural resource management at the local scale of a poor rural Sri Lankan village in a conservation buffer zone. This village experiences destruction of forests and human elephant conflict. The objective of this study is to gain an in-depth knowledge of residents' use and understandings of environmental resources, and to investigate if gender helps shape these factors. This study relies on a social sustainability conceptual framework. It tracks participation of local women and men in natural resource management, and in conservation within and outside of the Bibile community. Local nongovernmental organizations focus on …

Antimalarial Drug Discovery Using Triazoles To Overcome Chloroquine Resistance, Elias Sibhatu Tesfaselassie

Dissertations and Theses

Malaria is considered as one of the most prevalent and debilitating diseases affecting humans. Plasmodium falciparum is the most virulent form of the parasite which developed resistance to several antimalarial drugs. Chloroquine is one of the most successful antimalarials developed that is safe, effective, and cheap. However, its use has been limited due to the emergence of drug resistance. Click chemistry, particularly, the copper(I)-catalyzed reaction between azides and alkynes has shown to have a cutting-edge advantage in medicinal chemistry by its reliability, selectivity and biocompatibility.

Triazole-based antimalarials were synthesized via copper(I)-catalyzed alkyne-azide cycloaddition reaction by modifying the aliphatic chains terminal …

Hydrogeologic Investigation Of A Pumice Aquifer, Fremont/Winema National Forest, Oregon, Jonathan Michael Weatherford

Dissertations and Theses

The middle Holocene cataclysmic eruption of Mount Mazama blanketed Walker Rim, in south central Oregon, with 270 cm to 300 cm of pumice, causing capture of surface water systems by groundwater, stream relocation, and the formation of biologically diverse fens and seasonal wetlands. The pumice aquifer at Round Meadow, an 8.6 km² basin, hosts both a fen and seasonally ponded wetlands. The Round Meadow watershed lies within a closed basin between the upper Klamath and Deschutes river basins. As the highest meadow at Walker Rim, it is a relatively well-constrained system to study the effects of hydrological disruption.

A …

Rational Design Of Materials For The Protection Of Outdoor Metalworks, Natasja Alexandria Swartz

Dissertations and Theses

Protective coatings are commonly used to protect culturally significant works, such as outdoor sculptures and architectural elements. Given the valuable nature of such metalworks, there is a surprising lack of environmentally sustainable coatings available for their conservation. High performance clear coatings are not developed or thoroughly tested for compatibility and longevity on outdoor sculptures. This can make the implementation of both methods and materials, no matter how promising in a lab, a significant hurdle for the conservation science community. This dissertation work initially aims to replace high-VOC formulations such as acrylic lacquers and waxes currently used as protective coatings for …

Evaluation Of Data-Path Topologies For Self-Timed Conditional Statements, Navaneeth Prasannakumar Jamadagni

Dissertations and Theses

This research presents a methodology to evaluate data path topologies that implement a conditional statement for an average-case performance that is better than the worst-case performance. A conditional statement executes one of many alternatives depending on how Boolean conditions evaluate to true or false. Alternatives with simple computations take less time to execute. The self-timed designs can exploit the faster executing alternatives and provide an average-case behavior, where the average depends on the frequency of simple and complex computations, and the difference in the completion times of simple and complex computations. The frequency of simple and complex computations depends on …

The Design And Validation Of A Group Theory Concept Inventory, Kathleen Mary Melhuish

Dissertations and Theses

Within undergraduate mathematics education, there are few validated instruments designed for large-scale usage. The Group Concept Inventory (GCI) was created as an instrument to evaluate student conceptions related to introductory group theory topics. The inventory was created in three phases: domain analysis, question creation, and field-testing. The domain analysis phase included using an expert consensus protocol to arrive at the topics to be assessed, analyzing curriculum, and reviewing literature. From this analysis, items were created, evaluated, and field-tested. First, 383 students answered open-ended versions of the question set. The questions were converted to multiple-choice format from these responses and disseminated …

Tweakable Ciphers: Constructions And Applications, Robert Seth Terashima

Dissertations and Theses

Tweakable ciphers are a building block used to construct a variety of cryptographic algorithms. Typically, one proves (via a reduction) that a tweakable-cipher-based algorithm is about as secure as the underlying tweakable cipher. Hence improving the security or performance of tweakable ciphers immediately provides corresponding benefits to the wide array of cryptographic algorithms that employ them. We introduce new tweakable ciphers, some of which have better security and others of which have better performance than previous designs. Moreover, we demonstrate that tweakable ciphers can be used directly (as opposed to as a building block) to provide authenticated encryption with associated …

Scalable Equivalence Checking For Behavioral Synthesis, Zhenkun Yang

Dissertations and Theses

Behavioral synthesis is the process of compiling an Electronic System Level (ESL) design to a register-transfer level (RTL) implementation. ESL specifications define the design functionality at a high level of abstraction (e.g., with C/C++ or SystemC), and thus provide a promising approach to address the exacting demands to develop feature-rich, optimized, and complex hardware systems within aggressive time-to-market schedules. Behavioral synthesis entails application of complex and error-prone transformations during the compilation process. Therefore, the adoption of behavioral synthesis highly depends on our ability to ensure that the synthesized RTL conforms to the ESL description. This dissertation provides an end-to-end scalable …

Glacier Change On The Three Sisters Volcanoes, Oregon: 1900-2010, Justin George Ohlschlager

Dissertations and Theses

A glacier responds to changes in climate by subsequent retreat and advance as a result of changes in snow inputs and outputs. Understanding these changes is important because shrinking glaciers limit and diminish local water resources. They contribute to alpine runoff in the late-summer months by delaying the maximum runoff until late in the melt season. A comprehensive glacier and perennial snowfield inventory has not been completed for the Three Sisters in Central Oregon. Using aerial photography, Digital Elevation Models (DEMs), previous studies, and historical ground based photographs these glacier and perennial snowfields were defined and their surface area change …

The Influence Of Surface Chemistry On The Photoelectrochemical Properties Of Fes(2) Photoanodes, Qi Tong

Dissertations and Theses

The recurring theme of this dissertation is the correlation between FeS₂ surface chemistry and key electrical and electronic properties of FeS₂. Efforts have been made to identify and characterize the FeS₂ surface, investigate the photoelectrochemistry of FeS₂ photoanodes under anhydrous and anoxic conditions, and investigate the influence of deliberate surface chemistry on FeS₂ photoelectrochemistry.

Infrared reflection-absorption spectroscopy (IRRAS) was used to investigate a thin adsorbate layer on pyrite. The results showed that the combination of angle-dependent studies and computational efforts are a powerful tool for characterizing the pyrite surface.

The photoelectrochemistry of FeS_{2 …}

Novel Cryptographic Primitives And Protocols For Censorship Resistance, Kevin Patrick Dyer

Dissertations and Theses

Internet users rely on the availability of websites and digital services to engage in political discussions, report on newsworthy events in real-time, watch videos, etc. However, sometimes those who control networks, such as governments, censor certain websites, block specific applications or throttle encrypted traffic. Understandably, when users are faced with egregious censorship, where certain websites or applications are banned, they seek reliable and efficient means to circumvent such blocks. This tension is evident in countries such as a Iran and China, where the Internet censorship infrastructure is pervasive and continues to increase in scope and effectiveness.

An arms race is …

Pseudocapacitors For Energy Storage, Anuradha Venkataraman

Dissertations and Theses

Fluctuation in the demand for electrical power and the intermittent nature of the supply of energy from renewable sources like solar and wind have made the need for energy storage a dire necessity. Current storage technologies like batteries and supercapacitors fall short either in terms of power output or in their ability to store sufficient energy. Pseudocapacitors combine features of both and offer an alternative to stabilize the power supply. They possess high rates of charge and discharge and are capable of storing much more energy in comparison to a supercapacitor. In the quest for solutions that are economical and …

Characterization, Dna Binding And Cleavage Activities Of New Prodigiosin And Tambjamine Analogues And Their Cu²⁺ And Zn²⁺ Complexes, Karen Chichetu

Dissertations and Theses

Prodigiosins and tambjamines are natural compounds from bacterial and marine sources belonging to a family containing a common 4-methoxy-2,2'-bipyrrole core. These compounds have received a lot of interest due to their promising biological activities. Studies have suggested DNA as a potential therapeutic target for the natural prodigiosin and tambjamine due to their ability to facilitate oxidative DNA cleavage in the presence of Cu²⁺. Based on this we sought to study the metal binding activity of new prodigiosin and tambjamine analogues. A new prodigiosin analogue was synthesized and complexed with Cu²⁺. This revealed 1:1 complex formation between …

Steps Towards Deciphering The Post-Polyketide Synthase Tailoring Steps In The Phoslactomycin Biosynthesis Pathway, Patience Marimo

Dissertations and Theses

Phoslactomycins (PLMs) are a group of natural products belonging to a polyketides class. These polyketides are synthesized by sequential reaction catalyzed by a collection of enzymes activities called polyketide synthases. A polyketide is a large class of diverse compounds that are characterized by more than two carbonyl groups connected by single intervening carbon atoms. In other words, a polyketide is a polymer whose monomer is a ketide. The PLMs are also known as phosphazomycins or phospholines. These compounds were isolated based on antifungal and antitumor activities. This array of promising biological activities has stimulated research into the field of PLMs …

A Multivariate Modeling Approach For Generating Ensemble Climatology Forcing For Hydrologic Applications, Sepideh Khajehei

Dissertations and Theses

Reliability and accuracy of the forcing data plays a vital role in the Hydrological Streamflow Prediction. Reliability of the forcing data leads to accurate predictions and ultimately reduction of uncertainty. Currently, Numerical Weather Prediction (NWP) models are developing ensemble forecasts for various temporal and spatial scales. However, it is proven that the raw products of the NWP models may be biased at the basin scale; unlike model grid scale, depending on the size of the catchment. Due to the large space-time variability of precipitation, bias-correcting the ensemble forecasts has proven to be a challenging task. In recent years, Ensemble Pre-Processing …

Evaluating Global Sensitivity Analysis Methods For Hydrologic Modeling Over The Columbia River Basin, Maysoun Ayad Hameed

Dissertations and Theses

Global Sensitivity Analysis (GSA) approach helps to identify the effectiveness of model parameters or inputs and thus provides essential information about the model performance. The effects of 14 parameters and one input (forcing data) of the Sacramento Soil Moisture Accounting (SAC-SMA) model are analyzed by using two GSA methods: Sobol' and Fourier Amplitude Sensitivity Test (FAST). The simulations are carried out over five sub-basins within the Columbia River Basin (CRB) for three different periods: one-year, four-year, and seven-year. The main parameter sensitivities (first-order) and the interactions sensitivities (second-order) are evaluated in this study. Our results show that some hydrological processes …

Naturally Occurring Background Levels Of Arsenic In The Soils Of Southwestern Oregon, Heather Ann Hurtado

Dissertations and Theses

This study examines the natural background concentrations of arsenic in the soils of southwest Oregon, using new samples in addition to data collected from previous theses (Khandoker, 1997 and Douglas, 1999). The original 213 samples were run by ICP-AES with a reporting limit of 20 ppm, and only three samples had detected values. The original samples were tested again (2013) at a lower reporting limit of 0.2 ppm by ICP-MS, as were 42 new samples (2013), to better ascertain the natural levels of arsenic in undisturbed soils. The aim is to add to the existing DEQ data set, which has …

Defining The Terroir Of The Columbia Gorge Wine Region, Oregon And Washington, Usa Using Geographic Information Systems (Gis), Hilary Whitney

Dissertations and Theses

The Columbia Gorge Wine Region (CGWR) is an emerging wine producing area that extends for about 100km along the Columbia River in Oregon and Washington State in which the number of vineyards, wineries and physical terroir conditions have yet to be defined. To better understand the physical factors affecting Oregon and Washington wine, this project analyzes climate, topography, geology and soil at vineyards in the CGWR. This was accomplished using Geographic Information Systems, existing earth science databases and field work. The region, which includes the Columbia Gorge American Viticulture Area (AVA) and the southwest portion of the Columbia Valley AVA, …

Improved Gain Stability Of A Digital Imager Using A Charge Feedback Amplifier, Elliot Eckman Mylott

Dissertations and Theses

Digital imagers including Charge-Coupled Devices (CCD) are essential to most forms of modern photographic technologies. The quality of the data produced by digital imagers have made them an invaluable scientific measurement tool. Despite the numerous advantages of digital imagers, there are still factors that limit their performance. One such factor is the stability of the camera's gain, the ratio that dictates the imager's ability to convert incident photons to a measurable output voltage. Variations in gain can affect the linearity of the device and produce inaccurate measurements.

One of the factors that determines the gain of the camera is the …

Investigations Of The Air-Water Interface: A Structural Analysis Of Metallic Surface Films And Aquatic Surface Films By Comparative Microscopy, Randall William Smith

Dissertations and Theses

The air-water interface is an important natural boundary layer that has been neglected as an area of environmental field research. This study establishes that comparative microscopy can be an effective environmental method, and establishes that the term metallic surface films, is a more accurate descriptor than iron oxide surface films. This research shows that surface films are complex, often with layered structure, serve as habitat for significant biota, and act as a point of mineralization to several transition metal elements including manganese, iron, copper, nickel and zinc. This study demonstrates that surface films form under several conditions and can have …

Localized Ecological And Educational Effects Of Environmental Service-Learning In Portland, Oregon, Steven Matthew Braun

Dissertations and Theses

Environmental service-learning is an intentional educational experience(s) wherein learners engage in meaningful activities designed to serve the environment. Environmental service-learning activities vary according to their learning and service goals and include ecomanagement, persuasion, legal action, economic action and political action. The purpose of this mixed methods research was to explore the ecological and educational impacts of grades 6-12 environmental education, with special attention to environmental service-learning throughout Portland, Oregon.

Ecological impacts considered restoration and conservation outcomes of several environmental service-learning programs including plant communities, soils, litter removal and trail maintenance. Educational outcomes considered aspects of environmental literacy including locus of …