Physical Sciences and Mathematics Commons^™

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 …

Post-Silicon Functional Validation With Virtual Prototypes, Kai Cong

Dissertations and Theses

Post-silicon validation has become a critical stage in the system-on-chip (SoC) development cycle, driven by increasing design complexity, higher level of integration and decreasing time-to-market. According to recent reports, post-silicon validation effort comprises more than 50% of the overall development effort of an 65nm SoC. Though post-silicon validation covers many aspects ranging from electronic properties of hardware to performance and power consumption of whole systems, a central task remains validating functional correctness of both hardware and its integration with software. There are several key challenges to achieving accelerated and low-cost post-silicon functional validation. First, there is only limited silicon observability …

Hardware/Software Interface Assurance With Conformance Checking, Li Lei

Dissertations and Theses

Hardware/Software (HW/SW) interfaces are pervasive in modern computer systems. Most of HW/SW interfaces are implemented by devices and their device drivers. Unfortunately, HW/SW interfaces are unreliable and insecure due to their intrinsic complexity and error-prone nature. Moreover, assuring HW/SW interface reliability and security is challenging. First, at the post-silicon validation stage, HW/SW integration validation is largely an ad-hoc and time-consuming process. Second, at the system deployment stage, transient hardware failures and malicious attacks make HW/SW interfaces vulnerable even after intensive testing and validation. In this dissertation, we present a comprehensive solution for HW/SW interface assurance over the system life cycle. …

Novel Methods For Learning And Adaptation In Chemical Reaction Networks, Peter Banda

Dissertations and Theses

State-of-the-art biochemical systems for medical applications and chemical computing are application-specific and cannot be re-programmed or trained once fabricated. The implementation of adaptive biochemical systems that would offer flexibility through programmability and autonomous adaptation faces major challenges because of the large number of required chemical species as well as the timing-sensitive feedback loops required for learning. Currently, biochemistry lacks a systems vision on how the user-level programming interface and abstraction with a subsequent translation to chemistry should look like. By developing adaptation in chemistry, we could replace multiple hard-wired systems with a single programmable template that can be (re)trained to …

An Investigation Of The Role Of Alternate Numeration Systems In Preservice Teacher Mathematics Content Courses, Jodi I. Fasteen

Dissertations and Theses

Alternate numeration systems are common in preservice teacher (PST) mathematics curricula, but there is limited research on how to leverage alternate systems to promote the development of mathematical knowledge for teaching. I analyzed the role of alternate numeration systems in three ways. I conducted a thematic analysis of current PST textbooks to consider the role of alternate numeration systems in written curricula. I conducted a teaching experiment to analyze PSTs' mathematical activity as they engaged with a base five task sequence to reinvent an algorithm for multiplication. And I introduced problematizing mathematical contexts as a design heuristic, situating this within …

Climate Change Assessment In Columbia River Basin (Crb) Using Copula Based On Coupling Of Temperature And Precipitation, Yueyue Qin

Dissertations and Theses

The multi downscaled-scenario products allow us to better assess the uncertainty of the variations of precipitation and temperature in the current and future periods. Joint Probability distribution functions (PDFs), of both the climatic variables, might help better understand the interdependence of the two, and thus in-turn help in accessing the future with confidence. In the present study, we have used multi-modelled statistically downscaled ensemble of precipitation and temperature variables. The dataset used is multi-model ensemble of 10 Global Climate Models (GCMs) downscaled product from CMIP5 daily dataset, using the Bias Correction and Spatial Downscaling (BCSD) technique, generated at Portland State …

The Erosion Of Coastal Sediment And Regeneration Of Rhizophora Mangle Following Anthropogenic Disturbance On Turneffe Atoll, Belize, Heather Lyn Hayden

Dissertations and Theses

As communities and managers become aware of the long-term impacts of mangrove loss, estimated at 1-2% per year, interest in sediment erosion and mangrove rehabilitation has increased substantially. In this thesis project I 1) examine erosion rates within coastal fringing Rhizophora mangle ecosystems following mangrove clearing and compare these rates to accretion rates in intact mangroves; and 2) investigate the abiotic factors influencing mangrove seedling survival and regeneration of naturally colonizing R. mangle, in historic mangrove habitat after anthropogenic clearing.

Differences in erosion were compared between patches of open-coast intact and anthropogenically cleared R. mangle to quantify the sediment trapping …

The Response Of Zooplankton Communities In Montane Lakes Of Different Fish Stocking Histories To Atmospheric Nitrogen Deposition Simulations, Jeffrey Thomas Brittain

Dissertations and Theses

Freshwater ecosystems are subject to a wide variety of stressors, which can have complex interactions and result in ecological surprises. Non-native fish introductions have drastically reduced the number of naturally fishless lakes and have resulted in cascading food web repercussions in aquatic and terrestrial habitats. Additional anthropogenic influences that result from increases in global airborne emissions also threaten wildlife habitat. Atmospheric nitrogen deposition has been recognized as an anthropogenic contributor to acidification and eutrophication of wilderness ecosystems. Planktonic communities have shown declines in response to predation and shifts in composition as a result of nutrient inputs and acidification, both of …

Effects Of Selective Logging And Roads On Instream Fine Sediments And Macroinvertebrate Assemblages In The Clackamas Basin, Oregon, Paula Elizabeth Hood

Dissertations and Theses

Logging and associated skid trails, haul routes, and roads can have significant impacts on the magnitude and timing of sediments in streams in forested watersheds. Loss of vegetation, soil compaction, use of heavy logging equipment, and alteration of natural hydrologic patterns within the watershed can increase landslide rates, create erosion, and generate fine sediments. Selective logging, also called thinning, is a logging practice that leaves some trees within sale units unharvested. The ecological impacts of thinning on stream ecosystems are not fully understood and need further study. My hypothesis was that macroinvertebrate assemblages would be different in streams in non-reference …

Developing Key Sustainability Competencies Through Real-World Learning Experiences: Evaluating Community Environmental Services, Erin Lorene Anderson

Dissertations and Theses

This study focuses on sustainability in higher education and the competencies essential to address sustainability issues. Because sustainability issues are complex, "wicked", and dynamic, sustainability education programs need to reflect the interdisciplinary and collaborative nature of the field. Graduates who are competent in sustainability research and problem solving will have the knowledge, skills, and attitude necessary to analyze a sustainability problem systemically and comprehensively, then will construct and implement interventions to reach optimal sustainability solutions. To prepare graduates, sustainability education programs should facilitate the development of key sustainability competencies (Wiek, Withycombe, & Redman, 2011). Such programs provide an interdisciplinary approach …

Modeling The Optical Response To A Near-Field Probe Tip From A Generalized Multilayer Thin Film, A.J. Lawrence

Dissertations and Theses

The contrast mechanism in Kerr imaging is the apparent angle through which the plane of polarization is rotated upon reflection from a magnetic surface. This can be calculated for a well characterized surface given the polarization state of the incident light. As in traditional optical microscopy, the spatial resolution is limited by diffraction to roughly half the wavelength of the illumination light.

The diffraction limit can be circumvented through the use of near-field scanning optical microscopy, in which the illumination source is an evanescent field at the tip of a tapered optical fiber. A novel probe design for near-field optical …

Landforms Along The Lower Columbia River And The Influence Of Humans, Charles Matthew Cannon

Dissertations and Theses

River systems, such as the Columbia River in the Pacific Northwest, USA have been influenced by human activities, resulting in changes to the physical processes that drive landform evolution. This work describes an inventory of landforms along the Columbia River estuary between the Pacific Ocean and Bonneville Dam in Oregon and Washington. Groupings of landforms are assigned to formative process regimes that are used to assess historical changes to floodplain features. The estuary was historically a complex system of channels with a floodplain dominated by extensive tidal wetlands in the lower reaches and backswamp lakes and wetlands in upper reaches. …

The Blue Heron Wetland Restoration Project: Eradication Of Ludwigia Peploides Ssp. Montevidensis From The Blue Heron Wetlands Of Portland, Or, Alexander Staunch

Environmental Science and Management Professional Master's Project Reports

The Blue Heron Wetland Restoration Project (BHWRP) is an ongoing community driven effort to eradicate Ludwigia peploides ssp. montevidensis from a 3.5 acre ephemeral wetland in Portland, OR. Established in summer 2011 by the East Columbia Neighborhood Association (ECNA), the BHWRP consisted of an herbicide efficacy pilot study, widespread eradication effort, and establishment of a stewardship program. Ludwigia peploides ssp. montevidensis is an emerging threat to northwestern Oregon and the infestation within the Blue Heron Wetlands (BHW) represented one of the first known infestations of L. peploides ssp. montevidensis within the State of Oregon.

First observed within the BHW in …

Performance Metrics For Depth-Based Signal Separation Using Deep Vertical Line Arrays, John K. Boyle

Dissertations and Theses

Vertical line arrays (VLAs) deployed below the critical depth in the deep ocean can exploit reliable acoustic path (RAP) propagation, which provides low transmission loss (TL) for targets at moderate ranges, and increased TL for distant interferers. However, sound from nearby surface interferers also undergoes RAP propagation, and without horizontal aperture, a VLA cannot separate these interferers from submerged targets. A recent publication by McCargar and Zurk (2013) addressed this issue, presenting a transform-based method for passive, depth-based separation of signals received on deep VLAs based on the depth-dependent modulation caused by the interference between the direct and surface-reflected acoustic …

Development Of An Optical Method For The Detection Of Homocysteine As A Disease Biomarker Using Fluorescein-Aldehydes, Aabha Barve

Dissertations and Theses

Homocysteine is a natural occurring aminothiol. It is an intermediate product in the metabolism of methionine. Methionine is an essential amino acid required for protein synthesis. Metabolic irregularities disrupt homocysteine levels in plasma. Elevated homocysteine levels are directly linked to folate and cobalamin (vitamin B12) deficiencies, and are an independent risk factor for cardiovascular diseases. High homocysteine levels have also been associated with Alzheimer's, osteoporosis, renal failure, cancer, birth defects and pregnancy complications. The association of elevated homocysteine levels with cardiovascular disease and other diseases has generated great interest in the detection of homocysteine.

An optical method for the detection …

Facile Methods For The Analysis Of Lysophosphatidic Acids In Human Plasma, Jialu Wang

Dissertations and Theses

Lysophosphatidic acid (LPA) influences many physiological processes, such as brain and vascular development. It is associated with several diseases including ovarian cancer, breast cancer, prostate cancer, colorectal cancer, hepatocellular carcinoma, multiple myeloma atherosclerotic diseases, cardiovascular diseases, pulmonary inflammatory diseases and renal diseases. LPA plasma and serum levels have been reported to be important values in diagnosing ovarian cancer and other diseases. However, the extraction and quantification of LPA in plasma are very challenging because of the low physiological concentration and similar structures of LPA to other phospholipids. Many previous studies have not described the separation of LPA from other phospholipids, …

Spectroscopy, Nmr, And Electrochemistry Studies Of Protonated Aminophenyl/Pyridyl Porphyrins And Their Application In Hydrogen Evolution, Chenyi Wang

Dissertations and Theses

Spectrophotometric titrations for a full series of 4-aminophenyl/4-pyridyl meso-substituted porphyrins were carried out using methanesulfonic acid in DMSO to study the hyperporphyrin effect across different substitution patterns. The series included zero, one, two (cis and trans), three, and four meso(4-aminophenyl) groups, with the remaining meso substituents being 4-pyridyl groups. The peripheral pyridyl groups consistently protonate before the interior porphyrin pyrrole nitrogens, which protonate before the aminophenyl groups. Aminophenyl substituents increase the basicity of the pyrrole nitrogens and lead to distinctive hyperporphyrin spectra with a broad Soret band and a strong red absorption. The structure proposed to give rise to these …

Intersections Of Critical Systems Thinking And Community Based Participatory Research In Developing A Web Site For Autistic Adults, Dora Madeline Raymaker

Dissertations and Theses

People with disabilities, including those on the autism spectrum, comprise the world's largest minority and experience significant inequities in Internet use. Existing standards for accessible web sites are necessary but not sufficient without the direct engagement of end users in identifying access needs. Yet little is known about methods for effective engagement, and there are no systematically derived Web accessibility guidelines for autistic end users. Here I explore a hybrid approach to direct engagement using critical systems thinking (CST) and community based participatory research (CBPR) during the co-development of a healthcare-focused web site by the Academic Autism Spectrum Partnership in …

A Novel Approach To Flow And Sediment Transport Estimation In Estuaries And Bays, Hamed Moftakhari Rostamkhani

Dissertations and Theses

Reliable estimates of river discharge and sediment transport to the ocean from large tidal rivers are vital for water resources management, efficient river and harbor management, navigational purposes, and climate analyses. Due to the difficulties inherent in measuring tidal-river discharge, hydrological and sedimentological records are typically too short to adequately characterize long-term (decadal) trends. Also, uncertainties associated with observation and calibration of hydrological models suggest a need for more accurate methods based on longer records of hydrodynamic parameters (e.g. tides). Tidal theory indicates that tides and river discharge interact through quadratic bed friction, which diminishes and distorts the tidal wave …

Aberration Corrected Photoemission Electron Microscopy With Photonics Applications, Joseph P. S. Fitzgerald

Dissertations and Theses

Photoemission electron microscopy (PEEM) uses photoelectrons excited from material surfaces by incident photons to probe the interaction of light with surfaces with nanometer-scale resolution. The point resolution of PEEM images is strongly limited by spherical and chromatic aberration. Image aberrations primarily originate from the acceleration of photoelectrons and imaging with the objective lens and vary strongly in magnitude with specimen emission characteristics. Spherical and chromatic aberration can be corrected with an electrostatic mirror, and here I develop a triode mirror with hyperbolic geometry that has two adjacent, field-adjustable regions. I present analytic and numerical models of the mirror and show …

Modifications To A Cavity Ringdown Spectrometer To Improve Data Acquisition Rates, Gregory Alan Bostrom

Dissertations and Theses

Cavity ringdown spectroscopy (CRDS) makes use of light retention in an optical cavity to enhance the sensitivity to absorption or extinction of light from a sample inside the cavity. When light entering the cavity is stopped, the output is an exponential decay with a decay constant that can be used to determine the quantity of the analyte if the extinction or absorption coefficient is known. The precision of the CRDS is dependent on the rate at which the system it acquires and processes ringdowns, assuming randomly distributed errors. We have demonstrated a CRDS system with a ringdown acquisition rate of …

Leveraging Contextual Relationships Between Objects For Localization, Clinton Leif Olson

Dissertations and Theses

Object localization is currently an active area of research in computer vision. The object localization task is to identify all locations of an object class within an image by drawing a bounding box around objects that are instances of that class. Object locations are typically found by computing a classification score over a small window at multiple locations in the image, based on some chosen criteria, and choosing the highest scoring windows as the object bounding-boxes. Localization methods vary widely, but there is a growing trend towards methods that are able to make localization more accurate and efficient through the …

Energy Efficiency And Conservation Attitudes: An Exploration Of A Landscape Of Choices, Mersiha Spahic Mcclaren

Dissertations and Theses

This study explored energy-related attitudes and energy-saving behaviors that are no- or low-cost and relatively simple to perform. This study relied on two data sources: a longitudinal but cross-sectional survey of 4,102 U.S. residents (five biennial waves of this survey were conducted from 2002 to 2010) and a 2010 cross-sectional survey of 2,000 California residents. These two surveys contained data on two no- and low-cost behaviors: changing thermostat setting to save energy (no-cost behavior) and CFL installation behavior (low-cost behavior). In terms of attitudes, two attitudinal measures emerged from these data following a Cronbach's alpha and Confirmatory Factor Analysis (CFA): …

Sensible Air To Air Heat Recovery Strategies In A Passive House, Santiago Martin Rodriguez-Anderson

Dissertations and Theses

Due to rising energy costs and concerns about global climate change, high performance buildings are more in demand than ever before. With roughly 20% of the total energy consumption in the United States being devoted to residential use, this sector represents a significant opportunity for future savings. There are many guidelines and standards for reducing building energy consumption. One of the most stringent is the Passive House Standard. The standard requires that that air infiltration is less than or equal to 0.6 air changes per hour at a 50 Pascal pressure difference (ACH 50), annual heating energy is less than …

Enzymatic Control Of The Related Pathways Of Fatty Acid And Undecylprodiginine Biosynthesis In Streptomyces Coelicolor, Renu Singh

Dissertations and Theses

Streptomyces coelicolor produces fatty acids for both primary metabolism and for production of the components of natural products such as undecylprodiginine. Primary metabolism makes the longer and predominantly branched-chain fatty acids, while undecylprodiginine utilizes shorter and almost exclusively straight chain fatty acids. The first step in fatty acid biosynthetic process is catalyzed by FabH (β-ketoacyl synthase III), which catalyzes a decarboxylative condensation of an acyl-CoA primer with malonyl-acyl carrier protein (ACP). The resulting 3-ketoacyl-ACP product is reduced by NADPH-dependent FabG into 3-hydroxyacyl-ACP, which is dehydrated by FabA to form enoyl-ACP. The NADH-dependent FabI (InhA) completes the cycle. Subsequent rounds of …

Analyzing Free-Base Nicotine Content In The Particulate Matter Of Mainstream Tobacco Smoke Using A Headpace Solid-Phase Microextraction Gc/Ms Method, Christopher S. Motti

Civil and Environmental Engineering Master's Project Reports

The acid/base chemistry of cigarette smoke allows nicotine, the primary drug in mainstream tobacco smoke, to exist in protonated and free-base forms. Evidence suggests that most of the nicotine present in mainstream tobacco smoke is in the particle phase. α_fb is the fraction of particle-phase nicotine in the free-base form. The magnitude and rate of nicotine deposition in the respiratory tract is dependent on α_fb because only the free-base form of nicotine can volatilize from the particle phase of an inhaled aerosol and, once gaseous, rapidly deposit. This study develops a headspace solid-phase microextraction technique coupled with gas …

Geotechnical Statistical Evaluation Of Lahore Site Data And Deep Excavation Design, Aiza Malik

Civil and Environmental Engineering Master's Project Reports

Geotechnical characterization for foundation design is critical during preliminary planning, designing and feasibility studies of various engineering projects. In this research, an effort has been made to develop a geotechnical database for the city of Lahore, Pakistan. This database would aid geologists and engineers involved in the geotechnical design and planning of engineering projects in Lahore. The project area has been divided into zones geographically. Soil profiles have been developed for all zones, which provide ranges of soil properties and SPT-N values at regular intervals. Furthermore, the research also focuses on deep excavations in urban areas of Lahore, Pakistan and …

Dispersion Modeling Of Nitrogen Dioxide (No2) And Fine Particulate Matter (Pm2.5) From Backup Generators At Data Centers In Prineville, Oregon, Brooke E. Harmon

Civil and Environmental Engineering Master's Project Reports

As our society becomes increasingly dependent on digital communication (e.g., social media and email) and computerized storage (e.g., digitized medical records and government documents), tech giants such as Google, Facebook, and Apple are constructing and managing an increasing number of massive Internet data centers. These data centers house a network’s most critical systems and are vital to the continuity of daily operations. Requiring as much electricity as a medium size city, data centers rely on complex auxiliary power systems to prevent disruption to service. These backup systems consist of tens of multi-megawatt diesel-powered generators that release combustion byproducts, including over …

An Ornithological Investigation Of The Relationships Among Species Assemblages In Diverse Landscapes In Portland, Oregon, Trevor Attenberg

Environmental Science and Management Professional Master's Project Reports

This study involves geographic variables of the urban landscape and how they affect bird species assemblage. I utilized bird point count data from observation sites in the Portland, OR metropolitan region provided by Portland Environmental Services. Species data and its relationship with environmental variables were evaluated using Bray-Curtis Dissimilarity measurements together with Non-metric Multidimensional scaling (NMDS) to provide a clear image of the spatial relationships between sites. Land classification, water and canopy in 500 m buffers were quantified in order to describe important geographic variability among collection areas of bird data. Patterns indicating spatial trends in the urban landscape emerged. …