Index Catalog // ScholarsArchive@OSU

Characterizations of silicon-germanium nanocomposites fabricated by the marine diatom Nitzschia frustulum

Creator:: Liu, Shuhong
Abstract:: Marine diatoms are a class of microalgae that possess cell walls composed of silica nanoparticles. These organisms actively assimilate silicic acid Si(OH)4 from seawater, polymerize silicic acid to silica nanoparticles by a protein-mediated precipitation process, and then assemble the silica nanoparticles into intricate patterns that constitute the cell wall microarchitecture...
Resource Type:: Masters Thesis

The forest and the mainframe : the dynamics of modeling and field study in the Coniferous Forest Biome, 1969-1980

Creator:: Long, Tulley A.
Abstract:: In an initial research proposal of December 1969, the scientists of the Coniferous Forest Biome (CFB), an ecosystem study centered in the Pacific Northwest and part of the larger International Biological Programme (IBP), expressed optimism that computer simulations and systems modeling could transform empirical knowledge of the carbon, water, and...
Resource Type:: Masters Thesis

Case Study Examination of Programs Designed to Help Individuals and Communities through Fishery Disasters

Creator:: Shaw, Wesley D.
Abstract:: In 2000, the US Congress responded to the industry-wide constriction of the West Coast groundfish industry by allocating $5 million in disaster relief for Oregon, Washington, and California. Each state, with minimal federal oversight, designed and executed its own disaster response program to help impacted members of the fishing industry...
Resource Type:: Capstone Project

Metabolic uncoupling of Shewanella oneidensis MR-1, under the presence of excess substrate and 3,3’,4’,5 tetrachlorosalicylanilide

Creator:: Saini, Gaurav
Abstract:: Dissociation between catabolism and anabolism, generically termed “metabolic uncoupling”, has been studied for aerobic cultures of Shewanella oneidensis MR-1. Under conditions promoting metabolic uncoupling, the cell yield diminishes while the substrate utilization rate remains largely unchanged. The effects of excess substrate conditions and TCS addition on the metabolism of pyruvate...
Resource Type:: Masters Thesis

Integrating traceability with onboard handling to enhance product quality and marketability of Eastern Pacific troll-caught albacore tuna (Thunnus alalunga)

Creator:: Thompson, Michael J.
Abstract:: The fishing industry in the Pacific Northwest is a dynamic and highly competitive industry that must constantly respond to rapidly changing resource, regulatory and market forces. These forces have already had a significant impact on our fisheries and will continue to do so as we learn more about the biology...
Resource Type:: Masters Thesis

A Plan for Implementing a Clean Marina Program in Oregon

Creator:: Feindel, Kristin B.
Abstract:: Nonpoint source pollution is currently the major source of water pollution in Oregon as well as the United States as a whole. The Environmental Protection Agency designated marinas as one of the sources of nonpoint pollution to coastal waters. In an effort to reduce nonpoint pollution from marinas and to...
Resource Type:: Capstone Project

Introducing geographic information systems to grass seed growers in the Willamette Valley of Oregon

Creator:: Hedstrom, Keldah E.
Abstract:: Oregon is the number one producer of cool-season grass seed in the United States. The center of the grass seed industry of Oregon is located in the Willamette Valley, where about 470,000 acres of seed are grown. Innovative grass seed growers of the area are beginning to implement precision agriculture...
Resource Type:: Masters Thesis

Lahar hazard mapping of Mount Shasta, California : a GIS-based delineation of potential inundation zones in Mud and Whitney Creek basins

Creator:: McClung, Steven C.
Abstract:: Mount Shasta, the southernmost stratovolcano in the Cascade Range (41.4°N) has frequently produced lahars of various magnitudes during the last 10,000 yr. These include large flows of eruptive origin, reaching more than 40km from the summit, and studies have shown that at least 70 debris flows of noneruptive origin have...
Resource Type:: Masters Thesis

Using an internet map server and coastal remote sensing for education

Creator:: Bower, Peter A.
Abstract:: An Internet Map Server (IMS) web site was constructed with the goal of helping middle- through high-school students learn about ocean processes. This IMS was developed in conjunction with the activities of the Science & Math Investigative Learning Experience (SMILE) program, and for eventual use with the Oregon Coastal Atlas,...
Resource Type:: Capstone Project

Building and sharing spatial metaphors for thecatalogue of Oregon Marine and Coastal Information (COMCI)

Creator:: Cooper, Colin A.
Abstract:: Spatialization is an innovative way to expand searching capabilities for a marine/coastal reference database by using a metaphorical map framework to establish a sense of place for non-spatial information. Spatializing the Catalogue of Oregon Marine and Coastal Information (COMCI), a coastal reference database, enables the marine and coastal resource community...
Resource Type:: Capstone Project

Mapping vegetation using landsat TM and ETM+ in Eritrea

Creator:: Iyob, Biniam
Abstract:: The objective of this study was to examine vegetation and vegetation change in Eritrea over a period from the mid 1980s to 2002 using satellite remote sensing, and relate observed changes to the recent history of drought and war in the region. Specific objectives were (1) to examine vegetation change...
Resource Type:: Masters Thesis

An empirical statistical model relating winds and ocean surface currents : implications for short-term current forecasts

Creator:: Zelenke, Brian Christopher
Abstract:: An empirical statistical model is developed that relates the non-tidal motion of the ocean surface currents off the Oregon coast to forecasts of the coastal winds. The empirical statistical model is then used to produce predictions of the surface currents that are evaluated for their agreement with measured currents. Measurements...
Resource Type:: Masters Thesis

New configurations for RF/microwave bandstop and lowpass filters

Creator:: Peddibhotla, Harish V.
Abstract:: This thesis presents new, compact configurations for RF/microwave bandstop and lowpass filters for embedded passive applications. A simple design methodology is presented for designing the folded-transmission line filters on a microstrip platform. Unlike the conventional stub-loaded filter designs, the proposed folded-line filters will have practical dimensions for a wide range...
Resource Type:: Masters Thesis

Range-wide abundance and fluctuating asymmetry patterns of sagebrush-obligate passerine birds

Creator:: Krissman, Cortnie M.
Abstract:: North American sagebrush (Artemisia spp.) ecosystems are suffering from reductions in habitat extent and quality. Only about 50% of sagebrush remains from pre-settlement conditions, and much of the remaining habitat is fragmented or degraded by invasive species, fire suppression and overgrazing. Sagebrush-obligate species are experiencing population declines as a result...
Resource Type:: Masters Thesis

Phytoplankton shading of marine benthic macrophytes: Implications for intertidal community structure

Creator:: Kavanaugh, Maria T.
Abstract:: Previous observations of light levels and phytoplankton abundances along the Oregon coast demonstrated that phytoplankton attenuated light sufficiently to potentially limit the growth of intertidal macrophytes and therefore structure local intertidal communities. Inspired by this observation, in spring 2004, I initiated a study to quantify the direct and indirect benthic...
Resource Type:: Masters Thesis

Seasonal movement patterns and habitat use of westslope cutthroat trout in two headwater tributary streams of the John Day River

Creator:: Starcevich, Steven J.
Abstract:: Radiotelemetry was used to study the seasonal movements and habitat use of adult westslope cutthroat trout Oncorhynchus clarki lewisi in Roberts Creek and Rail Creek, headwater tributaries of the John Day River, Oregon, from September 2000 to December 2001. The objectives were to (1) describe adult cutthroat trout life history...
Resource Type:: Masters Thesis

Headwater stream macroinvertebrates of the H.J. Andrews Experimental Forest, Oregon

Creator:: Frady, Charles H.
Abstract:: Recent studies of headwater streams have demonstrated their importance to overall watershed biodiversity, nutrient cycling, and energy flux. However, little attention has been paid to long-term effects of forest harvest on macroinvertebrate communities in headwater streams. This study investigated headwater stream macroinvertebrate communities in the H.J. Andrews Experimental Forest, Oregon,...
Resource Type:: Masters Thesis

Effects of estuarine circulation patterns and stress on the migratory behavior of juvenile salmonids (Oncorhynchus sp.)

Creator:: Truelove, Nathan Kobun
Abstract:: For the first objective of this thesis, we attempt to understand the role of water flow and directionality in determining steelhead (Oncorhynchus mykiss) and spring/summer and fall Chinook (O. tschawytscha) migration patterns within the Columbia River Estuary and plume by integrating recent advances in biotelemetry and environmental observation and forecasting...
Resource Type:: Masters Thesis

Analysis of Betta splendens erythrophore responses to Bacillus cereus cultured in different media

Creator:: Austin, Melissa J.
Abstract:: Biological agents and their products commonly cause foodborne illnesses. In the United States it is estimated that there are over 76 million cases of foodborne illnesses each year, resulting in an economic loss of approximately $40 billion. These high figures demonstrate the need for bioassays that display a rapid and...
Resource Type:: Masters Thesis

Patterns in understory vegetation communities across canopy gaps in young, Douglas-fir forests of western Oregon

Creator:: Fahey, Robert T.
Abstract:: Canopy gap formation is a major factor contributing to maintenance of overstory species diversity and stand structure in forests and may be integral to development of understory shrub and herb layers as well. Acknowledgement of gap formation as a fundamental feature of natural forests has led to consideration of gaps...
Resource Type:: Masters Thesis

Comparison of time-domain and frequency-domain phase noise analyses

Creator:: Vytyaz, Igor
Abstract:: This thesis presents a comparison of time-domain and frequency-domain algorithms for phase noise calculation in oscillators. Floquet theory provides the mathematical foundation for these calculations and the numerical methods employ perturbation projection vectors (PPVs). The PPVs are an estimate of an oscillator's sensitivity to noise. The in-house circuit simulator SPICE3...
Resource Type:: Masters Thesis

Search for a repressor regulator of invasion in Mycobacterium avium

Creator:: Tripathi, Sanjai T.
Abstract:: Mycobacterium avium is an intracellular pathogen that is associated with disseminated infection, especially in patients with acquired immunodeficiency syndrome (AIDS). It appears that patients with AIDS acquire M. avium mostly through the intestinal tract, and that bacteria enter the intestinal wall at the terminal ileum. Previous studies have found that...
Resource Type:: Masters Thesis

White-breasted nuthatch density and nesting ecology in oak woodlands of the Willamette Valley, Oregon

Creator:: Viste-Sparkman, Karen
Abstract:: Habitat loss causes a reduction in available resources for wildlife, alters the configuration of remaining habitat, and may isolate wildlife populations. White-breasted nuthatches (Sitta carolinensis) are experiencing long-term population declines in the Willamette Valley of Oregon, where they are historically associated with oak woodlands. As secondary cavity-nesters, white-breasted nuthatches may...
Resource Type:: Masters Thesis

Persistence of spatial distribution patterns of coastal cutthroat trout in a Cascade mountain stream

Creator:: Novick, Marc S.
Abstract:: Previous research in South Fork Hinkle Creek suggested that coastal cutthroat trout exhibit an aggregated spatial pattern across multiple spatial scales. To evaluate the persistence of the observed abundance patterns and identify factors that affect those patterns, half-duplex passive integrated transponders (PIT-tags) were implanted in 320 coastal cutthroat trout (>...
Resource Type:: Masters Thesis

Influences of clearcut logging on macroinvertebrates in perennial and intermittent headwaters of the Central Oregon Coast Range

Creator:: Banks, Janel
Abstract:: This research was designed to broaden the understanding of how timber-harvest affects aquatic macroinvertebrates in perennial and intermittent headwater streams. This study compared emergent and benthic macroinvertebrate assemblages from 20 headwater streams in the central Oregon Coast Range that varied by harvest condition and flow duration. Through comparison of the...
Resource Type:: Masters Thesis

Four centuries of soil carbon and nitrogen change after severe fire in a Western Cascades forest landscape

Creator:: Giesen, Thomas William
Abstract:: Fire is a major disturbance process in many forests. Long-term studies of the biogeochemical effects of fires, especially on soils, are very rare. Consequently, long-term effects of fire on soils are often hypothesized from short-term effects. In a chronosequence study, I studied 24 western Cascades (Oregon) forest stands thought to...
Resource Type:: Masters Thesis

Fiber Bragg grating-tunable diode laser

Creator:: Ericksen, Doug
Abstract:: Continuously tunable diode laser sources coupled to single-mode fiber are useful sources for fiber Bragg grating (FBG) strain sensors. This paper describes the development and fabrication of such a device. An introduction is given describing applications of tunable lasers and some of the different methods of creating a tunable diode...
Resource Type:: Masters Thesis

Nursery container weeds response to modification of substrate pH, substrate particle size and applied nitrogen form

Creator:: Wada, Sugae
Abstract:: Experiments were conducted to determine the influence of cultural management practices on weed growth in nursery containers. Experiments 1 and 2 evaluated the effects of dolomitic lime rate and application method on substrate pH, creeping woodsorrel (Oxalis corniculata L.) establishment in containers, and growth of azalea (Rhododendron ‘Rosebud’) and pieris...
Resource Type:: Masters Thesis

A domain-specific embedded language for probabilistic programming

Creator:: Kollmansberger, Steven
Abstract:: Functional programming is concerned with referential transparency, that is, given a certain function and its parameter, that the result will always be the same. However, it seems that this is violated in applications involving uncertainty, such as rolling a dice. This thesis defines the background of probabilistic programming and domain-specific...
Resource Type:: Masters Thesis

Dependency speculation in dynamic simultaneous multi-threading

Creator:: Nelson, Jarrod A.
Abstract:: The purpose of this thesis is to explore dependency speculation in Dynamic Simultaneous Multi-Threading (DSMT). DSMT is a microprocessor architecture which attempts to extract Thread Level Parallelism (TLP) from single-threaded programs at run-time. This is accomplished by running multiple iterations of program loops in parallel. The DSMT architecture was originally...
Resource Type:: Masters Thesis

Degradation kinetics of taxol using mass spectroscopy

Creator:: Zhang, Jun
Abstract:: Paclitaxel is a very important anticancer drug commonly called Taxol®. We know from previous work (Hoffman, et al., 1998) that Taxol exists in filbert, Corylus avellana L. material. Quantification of Taxol in filbert plant material is painstaking and hitherto was accomplished by rapidly processing single batches in a complicated procedure...
Resource Type:: Masters Thesis

Effects of release from suppression on hydraulic architecture, photosynthetic capacity and functional wood characteristics in Douglas-fir and western hemlock

Creator:: Renninger, Heidi
Abstract:: Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), a shade intolerant species, and western hemlock (Tsuga heterophylla (Raf.) Sarg.), a shade tolerant species, were compared to learn more about the temporal pattern of release from suppression in both species, whether hydraulic architecture or photosynthetic capacity constrain release and how wood functional properties change...
Resource Type:: Masters Thesis

Noise optimization for low-voltage CMOS audio preamplifier systems

Creator:: Brown, Matthew Eugene
Abstract:: There is a large and growing market for portable consumer audio products with very small size. As the size of these products is reduced, the area occupied by batteries becomes significant and hence limits the number of batteries to one. In order to build such small products, high levels of...
Resource Type:: Masters Thesis

An efficient and accurate method of estimating substrate noise coupling in heavily doped substrates

Creator:: Arunachalam, Sasi Kumar S.
Abstract:: This thesis presents a Z-parameter based model to predict the substratenoise coupling between two contacts in a heavily doped substrate for frequenciesless than 2 GHz. The empirical model is scalable with contact size and spacingsbetween the contacts and model parameters can be readily extracted from simu-lated or measured data. The...
Resource Type:: Masters Thesis

A comparative study of lowpass continuous-time delta-sigma modulators with pulse-shaped DACs

Creator:: Fang, Jie
Abstract:: Recently, continuous-time ΔΣ modulators are appearing increasingly often in both the literature and the marketplace due to their features of inherent antialiasing and relaxed requirements for opamp and so on. However, several nonideal factors such as clock jitter, excess loop delay, inter-symbol interference and so on, degrade the SNR performance...
Resource Type:: Masters Thesis

Discrete trap modeling of thin-film transistors

Creator:: Yerubandi, Ganesh Chakravarthy
Abstract:: A discrete trap model is developed and employed for elucidation of thin-film transistor (TFT) device physics trends. An attractive feature of this model is that only two model parameters are required, the trap energy depth, E[subscript T], and the trap density, N[subscript T]. The most relevant trends occur when E[subscript...
Resource Type:: Masters Thesis

Implementation of an ultra-wideband transceiver for sensor applications

Creator:: Jann, Benjamin J.
Abstract:: Ultra-wideband (UWB) radio is the transmission of data using an extremely wide bandwidth and very low power spectral density. In this thesis, the mereits and challenges of UWB architectures versus conventional narrowband architectures will be compared. Pulsed UWB systems can be implemented with very simple architectures. These advantages make UWB...
Resource Type:: Masters Thesis

Planning in multi-agent partially observable domains using sparse sampling

Creator:: Donneau-Golencer, Thierry D.
Abstract:: A large number of sequential decision-making problems in uncertain environments can be modeled as Markov Decision Processes (MDPs). In such settings, an agent can observe at each time step the state of the environment and then executes an action, causing a stochastic transition to a new state of the environment...
Resource Type:: Masters Thesis

End user software engineering features for both genders

Creator:: Sorte, Shraddha
Abstract:: Previous research has revealed gender differences that impact females’ willingness to adopt software features in end users’ programming environments. Since these features have separately been shown to help end users problem solve, it is important to female end users’ productivity that we find ways to make these features more acceptable...
Resource Type:: Masters Thesis

Garbage in, garbage out? An empirical look at oracle mistakes by end-user programmers

Creator:: Phalgune, Amit
Abstract:: End-user programmers, because they are human, make mistakes. However, past research has not considered how visual end-user debugging devices could be designed to ameliorate the effects of mistakes. This paper empirically examines oracle mistakes mistakes users make about which values are right and which are wrong to reveal differences in...
Resource Type:: Masters Thesis

A stochastic time-to-digital converter for digital phase-locked loops

Creator:: Ok, Kerem
Abstract:: Digital phase-locked loops (PLLs) have been receiving increasing attention recently due to their ease of integration, scalability and performance comparable to their analog counterparts. In digital PLLs, increased resolution in time-to-digital conversion is desirable for improved noise performance. This work describes the design and simulation of a stochastic time-to-digital converter...
Resource Type:: Masters Thesis

A MOSCAP pipeline pseudo passive DAC

Creator:: Behera, Prachee Shree
Abstract:: The design of a 10-bit pipelined charge redistribution DAC employing MOSCAPs biased in their accumulation mode is presented in this thesis. A switched capacitor filter and output buffer have also been designed for the system. The effect of MOSCAP nonlinearity on the performance of the pipelined charge redistribution DAC has...
Resource Type:: Masters Thesis

Oscillators and phase locked loops for space radiation environments

Creator:: Vandepas, Martin
Abstract:: Circuits operating outside the earth’s atmosphere are more vulnerable to cosmic radiation and require special design consideration. The purpose of this work is to explore methods of mitigating the effect of radiation in phase locked loop (PLL) circuits. Several voltage controlled oscillators (VCOs) and two complete PLLs are designed and...
Resource Type:: Masters Thesis

Design techniques for radiation hardened-phase locked loops

Creator:: Nemmani, Anantha Nag
Abstract:: Spacecrafts experience radiation in the course of their operation and all electronic equipment on board these spacecrafts has to be designed to withstand the effects of this radiation. This thesis describes the effects of total ionization dose (TID) and single event transients (SET) in phase-locked loops - an important circuit...
Resource Type:: Masters Thesis

Influence of adjustable speed drive on induction motor fault detection using stator current monitoring.

Creator:: Al-Shahrani, Ali
Abstract:: The detection of motor faults at their incipient stage is of prime importance to any industrial plant. The introduction of adjustable speed drives has improved the control and the efficiency of induction motors, however, this has changed the nature of motor faults and how they can be detected. Current signature...
Resource Type:: Masters Thesis

A test fixture and deembedding procedure for high-frequency substrate characterization

Creator:: Webb, Kyle M.
Abstract:: At frequencies exceeding 1-2 GHz, the substrate network models used in substrate coupling simulation must account for the reactive nature of the substrate. Unlike at low frequencies, where the purely resistive substrate models can be validated through DC resistance measurements, these high-frequency models, comprising reactive components, must be validated through...
Resource Type:: Masters Thesis

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