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Transmission Line Parameters Estimation for Series Compensated Line, Mutually Coupled Line, and Short Line Using Synchrophasor Measurements
No full textThe accuracy of transmission line parameters is crucial for many power system applications such as power flow, relay settings, fault location, and voltage stability. Currently, there are many methods to estimate line parameters for both transposed and untransposed line, but most of them consider only positive sequence parameters and, only a few estimate positive sequence parameters for a series compensated line and partly mutually coupled lines operate at different voltages. Most power system grids in the world used phasor measurement units (PMUs) to at least a limited extent. Synchrophasor technology is used in this research, which takes the time synchronized measurements of voltages and currents as phasors at both ends of the line. In this research, a new method is developed to estimate line parameters for a series compensated line. The errors in synchrophasor measurements as a result of low-frequency oscillation of the series capacitor in response to a fault, was treated as bad data. The estimation was performed by creating different cases of unbalanced currents in the system and using a Least Trimmed Square (LTS) estimator to detect and reject the bad data. Then, positive, negative, and zero sequence parameters were estimated using the weighted least square method. A comparison between Chi-square which, is a conventional method to detect bad data, and the LTS has also been done. A new method was developed to estimate the line parameters for mutually coupled lines operated at different voltages. Two separate sets of equations have been built to convert the non-linear equations to linear equations. One set of equations to estimate the shunt capacitance and the second set are for estimating the series and mutual impedance of the targeted line. The method is based on taking one of the lines out of service and creating different states of unbalanced conditions anywhere else in the system. The sensitivity of current transformers introduces a challenge for estimating short parameters. The LTS is used again to detect and reject the sensor error measurements for different inductive reactance to resistance (X/R) ratios. Initial simulations are performed using ATP to simulate the power system. Next a system of two commercial synchrophasor units, Real Time Digital Simulator (RTDS), a phasor data concentrator (PDC), a GPS satellite-synchronized clock, are used to validate the performance of the new method for series compensated lines. PSCAD/EMTDC simulation is used to validate the developed estimation method for the mutually coupled lines. The ability of the proposed methods to estimate line parameters will be evaluated along with assessing what would be needed to apply them in practice.doctoral, Ph.D., Electrical and Computer Engineering -- University of Idaho - College of Graduate Studies, 2019-0
Remotely Sensed Metrics Help Map Range-Wide Habitat Suitability and Identify Habitat Restoration Priorities for an Endangered Marsh Bird
No full textManagers and policy-makers are often confronted with the difficult task of allocating limited resources to conservation efforts and habitat management actions. Data to inform the allocation of resources can be collected in the field, but the high costs and logistical complications of field-based approaches often render large scale field data collection efforts impractical. Satellite remote sensing has become increasingly important to informing conservation decisions because it can serve as an efficient means to collect earth observations. For example, satellite-derived data have been used to track ecosystem degradation, monitor restoration efforts, map land cover, and predict biodiversity. Significant challenges still hinder the wider application of satellite remote sensing techniques in conservation planning. For instance, using satellite imagery often requires expertise in remote sensing techniques, access to expensive image processing software, and the capacity to manage large datasets. These challenges hinder the development of useful information (e.g., habitat assessments) and the dissemination of results (e.g., maps of habitat suitability) to land managers and policy-makers. We used publicly available Landsat data and generalized linear mixed models to link satellite-derived metrics of marsh condition with the relative abundance of the federally endangered Yuma Ridgway’s rail (Rallus obsoletus yumanensis). We followed a rigorous model selection process to: 1) identify the most appropriate set of marsh condition variables that best predict rail abundance; 2) optimize the temporal scale at which we measured these predictors; 3) identify the optimal statistical distribution with which to model rail abundance; and 4) account for the spatio-temporal dynamics of a fragmented and stochastic ecosystem (freshwater emergent marshlands). Our model selection process allowed us to objectively select the most parsimonious model for inference. We applied the results of our rail abundance models to generate range-wide predictive maps of habitat suitability at a fine spatial grain (30 m). Such maps will help target management actions, both spatially and temporally, throughout the range of this endangered bird. Moreover, we developed a reliable way to detect wetland disturbances with Landsat imagery, which may help determine how frequently to re-apply management actions. We addressed many of the challenges facing the use of satellite remote sensing by working with the web-based (and freely available) Google Earth Engine to process large datasets of Landsat imagery and generate maps of habitat suitability. These maps of habitat suitability are shareable, interactive, and easy to update and will enhance our ability to prioritize management actions for recovery of an endangered bird. We focused on the Yuma Ridgway’s rail, but our methods could be applied to other species of conservation concern.masters, M.S., Natural Resources -- University of Idaho - College of Graduate Studies, 2019-0
Building the Oceanic Lithosphere: Geophysical Analysis and Numerical Simulations of Rheology and Dynamics in the Formation of Transform Faults and Hotspot Island Chains
No full textThe oceanic lithosphere comprises over half of the Earth’s surface. In this dissertation, I explore rheologic characteristics and dynamic evolution of the lithosphere through a series of investigations of mid-oceanic ridge transform faults, fracture zones, and hotspot island chains. I use geophysical observations from satellite- and ship-based collections to measure structure, deformation, and melt fluxes as well as constrain dynamic numerical simulations of long-term lithosphere movements. From these observations and models, I characterize the heterogeneous strength of the lithosphere across length scales and interpret dynamic behavior in rising thermal plumes from the Earth’s mantle.doctoral, Ph.D., Geology -- University of Idaho - College of Graduate Studies, 2019-0
Management of Kokanee in Idaho Lakes: Sampling Techniques, Growth Disparities, and Mysis-Kokanee Interactions
No full textKokanee Oncorhynchus nerka provide valued recreational fisheries, and also serve as a prey resource for economically, socially, and ecologically important fishes. As such, management of kokanee is a major focus of natural resource agencies. Despite considerable research over the last 60 years, several questions remain regarding the management of kokanee in Idaho. Specifically, uncertainty surrounding common sampling techniques for kokanee undermine confidence in population assessments for the species. Additionally, observed growth differences between kokanee breeding groups (e.g., early-run, late-run) raise questions about the potential influence of genetics and hatchery practices on the population structure of the species. Finally, the potential mechanisms underlying competitive interactions between kokanee and Opossum Shrimp Mysis diluviana (hereafter Mysis) are largely unresolved. In an effort to improve the understanding of the ecology and management of kokanee, we sought to 1) evaluate the size selectivity of different sampling techniques for kokanee, 2) evaluate the potential causes of growth disparities among kokanee breeding groups (early-run, late-run) in Idaho, and 3) investigate how ontogenetic shifts in diet in kokanee potentially influence competitive interactions with Mysis.doctoral, Ph.D., Natural Resources -- University of Idaho - College of Graduate Studies, 2019-0
Tillage Management Effects on Subsurface Nitrate Transport to Artificial Drain Lines Using Ditributed Temperature Sensing
No full textIn the Palouse Region, farmers have been adopting no-tillage (NT) management practices over the last 30 years. There is a growing body of evidence that suggests long-term NT practices leads to the establishment of macropore networks through the preservation of earthworm burrows and root channels. These macropores may act as preferential flow paths in the vadose zone. The goal of this study is to quantify and compare the effects of long-term tillage management practices on subsurface preferential flow using distributed temperature sensing technology (DTS) and to assess changes in hydrologic and nitrate transport dynamics and pathways. In this paired watershed study (November 2016 to April 2017) temperature was used as a tracer as snowmelt drained to two artificial drain lines under different tillage management, one draining a conventional tillage (CT) field and the other draining a no-till (NT) field. We found evidence that infiltrated water on the NT field travelled through the vadose zone preferentially as compared to the CT field by observing greater variability of water flow to fiber-optic cables installed in the artificial drain lines (2.2 times the number of temperature decreases greater than 0.35 ºC along each cable), rapid flushing of water through the soil profile (during five early season discharge events the temperature of the drain line reached a minimum temperature 20.9 hours before the CT field), greater relative drops and rapid recovery of EC in NT drainage water during discharge events and early season flushing of nitrate through the soil profile. Major differences were also found in the predominant hydrologic and nitrate transport pathways. Runoff from the CT field (162.8 mm) was much greater than from NT field (0.8 mm) and drain line discharge was 1.4 times greater on the NT field (126.7 mm). On the NT field 100% of nitrate load came through the drain line while on the CT field 55% of the nitrate load came through the drain line and 45% came from surface runoff. Despite these changes in hydrologic flow paths and nitrate transport path ways there was no evidence that tillage management had any effect on the magnitude of total nitrate export to surface water.masters, M.S., Water Resources -- University of Idaho - College of Graduate Studies, 2019-0
Impacts of Authentic Science Experiences for Underserved Youth: Design, Research, and Evaluation of an Upward Bound Watershed Science Summer Course
No full textBased on the findings of this doctoral research project, out-of-school science experiences targeting low-income and first-generation youth (LIFG) have the power to positively impact STEM career interest and science identity. This body of work contributes a program design case, research, and evaluation of an authentic science summer program designed for an Upward Bound Math Science (UBMS) program at the University of Idaho. Using a model of instructional design, I use the first article to outline the development of a watershed science-focused summer program designed for LIFG high school students, aligned with the UBMS goal of making science degrees/careers more accessible. In article two, I apply a model social influence theory to understand student integration into science at the program level, investigating science identity, self-efficacy, science values, and intention to pursue STEM as program outcomes using a convergent mixed method, quasi-experimental design. Finally, I conducted an exploratory case study evaluation in article three to provide a summary of the summer program in two parts: (a) a report on program effectiveness for facilitating accessibility of science degrees/careers; and (b) a discussion of recommendations and implications for future Upward Bound summer program improvement. I recommend that future programming and research develop strategies to address the barriers to STEM identified through this work including fixed mindsets, fixed theories of interest, and low academic achievement.doctoral, Ph.D., Water Resources -- University of Idaho - College of Graduate Studies, 2019-0
Evaluating the Use of Hyperspectral Remote Sensing and Narrowband Spectral Vegetation Indices to Diagnose Onion Pink Root at the Leaf and Canopy Level
No full textThe Treasure Valley of Idaho and Eastern Oregon produces around 30% of the nation’s annual summer storage onion crop. To profitably produce an onion crop, growers must attain both high total yields and bulbs of sufficient size. Onion pink root (causal agent Setophoma terrestris) is capable of destroying the onion root system during the growing season, resulting in foliar symptoms that imitate those of nutrient or drought stress and bulbs that are underdeveloped and small in size. The aim of this study was to evaluate the usefulness of hyperspectral remote sensing and narrowband spectral vegetation indices (SVIs) as a tool to diagnose onion pink root in the field and discriminate its symptoms from those of nitrogen and water stress. A field experiment was established in Parma, ID in 2018 and 2019 to which 3 moderate and consistent individual stress treatments were applied to the onion cultivars SV4643NT and Vaquero. Pink root, nitrogen, and drought stress were imposed using a combination of natural inoculum, soil fumigation (chloropicrin), fertilizer, and drip irrigation. Onion samples and hand-held, hyperspectral radiometric measurements were collected weekly from the time of bulb initiation to the time of plant maturity to study the effects of stress on onion phenotype and reflectance at the leaf and canopy level. Results from the destructive sampling suggest that the proportion of diseased roots is significantly reduced by soil fumigation with chloropicrin. Furthermore, the total nitrogen content of onion leaves sampled from the nitrogen stressed (non-fertilized) plots were significantly reduced from the content of those taken from optimally fertilized plots. All stress treatments significantly reduced plant biomass, although not at the same growth stage nor to the same extent. Reflectance spectra were analyzed using 40 established SVIs. Preliminary analysis determined a similar relative relationship among treatments for most of the SVIs utilized. Three SVIs: triangular vegetation index (TVI), normalized difference vegetation index (NDVI), and optimized soil-adjusted vegetation index (OSAVI) were selected for detailed analysis. Only small variations in SVI value were observed between treatments at the leaf level. At canopy-level, stress treatments consistently lowered index values, though not always significantly and not always to the same degree. Results from standard regression analysis suggest that SVI value is closely related to the biomass of SV4643NT (R2 = 0.67 to 0.79) and Vaquero (R2 = 0.73 to 0.83) onions, likely because of the direct relationship between plant biomass and parameters which account for the fraction of vegetation that covers the soil (such as leaf area index (LAI)). Overall, we found that SVIs, particularly those which include a band in the near-infrared region (700-1000 nm), are overwhelmingly sensitive to variation in canopy LAI as opposed to other vegetation parameters such as plant pigment composition (i.e. chlorophyll) in scenarios where the crop canopy does not completely cover the soil. This presents a challenge to the practical use of hyperspectral remote sensing and narrowband SVIs as a tool to diagnose onion stress at the canopy level.masters, M.S., Plant, Soil and Entomological Sciences -- University of Idaho - College of Graduate Studies, 2019-1
Tissue Culture and Genetic Transformation of Hexaploid Wheat for Stripe Rust Resistance
No full textWheat stripe rust, caused by Puccinia striiformis f.sp tritici (Pst), can be a highly destructive disease, resulting in significant yield losses in the Pacific Northwest in epidemic years. Brundage, a top-quality, high-yielding, soft white winter wheat variety has been superseded in the last five years due to its susceptibility to the disease. Because of climate conditions in this region, infection by Pst is common. Therefore, introgression of one or more Pst resistance genes into regionally adapted genetic backgrounds is highly desirable. The goals of the present study were, firstly, to establish a tissue culture and genetic transformation system for two regionally adapted varieties: Brundage and UI Platinum. Secondly, to use genetic transformation to improve stripe rust resistance in Brundage. Six wheat varieties were initially tested for the tissue culture response of immature embryos in order to determine their regenerability into whole plants. The results indicated that there were two related groups in regard to regeneration; Fielder, Florida 303, and UI Platinum had similar but higher regeneration capacities than Florida 301, Florida 302, and Brundage. Fielder and UI Platinum are spring varieties, Florida 301 and 303 are facultative, and Florida 302 and Brundage are winter types. The shoot regeneration rate mean was highest for Fielder at 51.72% and lowest for Brundage at 9.90%. Five of aforementioned genotypes, excepting UI Platinum, were used in biolistic bombardment with the Yr28 gene, which is derived from Aegilops tauschii and confers all-stage resistance to stripe rust. There was no significant difference in the transformation rate of each genotype. The Fielder genotype had the highest mean transformation rate at 0.43% with a total of four transformed plants produced from 1,009 embryogenic calli, and Florida 301 had the lowest mean transformation rate at 0.13%, with one transformed plant produced from 952 embryogenic calli. However, the most successful replicate, KJ3, was completed with the Brundage genotype and had a transformation rate of 1.54% with three transformed plants produced from 195 embryogenic calli. Fifteen of the 33 replicates completed produced no plants whatsoever, and eight replicates produced plants, but those plants did not test positive for the for the Yr28 transgene. In total, 24 transformed plants were produced, 11 of which were from the Brundage genetic background, four from Fielder and Florida 302 respectively, three from Florida 301, and one from Florida 303. Ten of the T0 transformed plants showed distinctively resistant phenotypes, six of which were from the Brundage background. Lines carried to the T1 generation displayed genetic segregation for the Yr28 transgene. Some T1 plants were associated with stripe rust resistance. All wheat genotypes selected for transformation were confirmed to be susceptible to the currently prevalent Pst races. The insertion of Yr28, or other Pst-resistance genes, is highly desirable to impart disease resistance in wheat that is otherwise limited in this regard. The current study illustrated that unexploited genes from wild wheat relatives can be harnessed for wheat improvement.masters, M.S., Plant, Soil and Entomological Sciences -- University of Idaho - College of Graduate Studies, 2019-1
Magnetic Resonance Image Based Quantification of Ophthalmic Changes in Long-Duration Spaceflight Astronauts
No full textExtended visits to microgravity have resulted in many ophthalmic abnormalities in some long-duration spaceflight astronauts. In combination these symptoms define the spaceflight associated neuro-ocular syndrome (SANS). Theorized to be a result of increased intracranial pressure (ICP) due to headward fluid shifts, these issues often persist for some time after return to Earth and will likely worsen on extended spaceflight ventures such as visits to Mars. In particular, changes to the optic nerve, optic nerve sheath, and the posterior optic globe may have an underlying impact on ocular function. The following studies provide reliable, automated, and quantitative analysis of ON and ONS tortuosity and cross-sectional area as well as volumetric globe deformation in long-duration spaceflight astronauts. High resolution MR images were collected pre-flight as well and at five recovery timepoints post-flight for (n = 10) astronauts, extending to one year after return for 6-month missions to the international space station. Methods were developed, reliability tested, and applied to assess ON tortuosity, ON and ONS cross-sectional areas, and volumetric globe deformation in all subjects. There were no spaceflight-associated changes in tortuosity or cross-sectional areas while changes to globe deformation were quantified. The average and percent change in tortuosity, ON area, ONS area, and volumetric globe deformation immediately post-flight was -0.06 ± 0.42 mm (-0.9%), 0.58 ± 2.53 mm2 (6.7%), -0.88 ± 2.35 mm2 (-3.7%), and 10.76 ± 11.93 mm3 respectively. Tortuosity and ON/ONS area values at recovery timepoints were relatively consistent over time. Globe deformation values generally decreased across these timepoints indicating recovery after return to Earth. Quantitative highly automated MRI based assessment of the ocular structures could help our understanding of SANS and assist its prevention.masters, M.S., Biological & Agricultural Engineering -- University of Idaho - College of Graduate Studies, 2019-1
Island Connections: Soils, Water, Vegetation, and Education in a Small Low Island Context
No full textAtoll islands (AI) are home to unique ecosystems found across a wide range of climatic conditions. The remoteness and small size of these islands limits studies about physical and biological relationships that may be important for adaptation and survival of island species. This dissertation combines both physical studies, remote sensing studies, and educational outreach efforts to increase our understanding of AI. Chapter one of this dissertation explores the mechanisms by which Pisonia grandis, R. Br., a native island tree species, alters the soil environment with respect to water. Chapter two validates a method for mapping AI island vegetation from moderate-resolution Landsat 7 ETM+ imagery using multiple endmember spectral mixing analysis. Chapter three described a series of data-driven lesson plans developed about the Pacific Marine National Monument system, and chapter four, which focuses on education but not AI, quantifies changes in scientific literacy experienced by students participating in an experiential water focused science program, the Confluence Project, in northern Idaho.doctoral, Ph.D., Water Resources -- University of Idaho - College of Graduate Studies, 2019-0