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Spin-Orbit Misalignment of Planets Orbiting High-Mass Stars: Observations and Techniques Using NASA's Kepler Telescope
No full textThis dissertation summarizes my graduate research on exoplanets orbiting high-mass, rapidly-rotating stars using NASA's Kepler telescope. The overall theme of this research bridges exoplanet observations with existing planet formation and evolution theories with the goal of constraining the mechanisms that cause spin-orbit misalignment. This phenomenon occurs surprisingly often around high-mass stars, suggesting that planet formation in these systems may be fundamentally different than for solar-type stars. And while many explanations have been put forth to explain spin-orbit misalignment, its root cause is still unknown. The research in this dissertation helps solve this problem by observing spin-orbit misalignment around high-mass stars and testing my findings against existing misalignment hypotheses to shed light on the formation processes taking place around high-mass stars.doctoral, Ph.D., Physics -- University of Idaho - College of Graduate Studies, 2018-1
The Impact of Grid-connected Photovoltaic Voltage Sourced Converter with Negative Sequence Decoupling Control on Protection Scheme Behavior
No full textThis thesis focuses on grid-connected PV systems and their impact on protection scheme performance during system fault conditions. The main objective of this work is to design a simulation model that can simulate the response of the system during different fault applications. The ATP program is used to model the grid-connected PV system along with the VSC control schemes based on the decoupled double synchronous reference frame method. The ATP model can be used as a teaching tool in courses and for research purposes. Different types of faults are applied to the power distribution system, with a distance protection element (21) proposed to protect the distribution system. An inverse-time overcurrent element (51) is used to protect the collector system on the ac-side of the VSC. Due to the characteristics of the VSC, it is controlled to limit the fault current contribution to less than 1.2 pu of the maximum current value. This causes the protection elements to either not trip or not trip correctly. In addition, due to the limited fault current and the weak source of the grid-connected PV system compared to the grid system source, the mho distance element mislocates the fault location. It calculates that the apparent fault location is much closer to the PCC than it actually is. This study indicates that the performance of the supervised distance element and the inverse-time overcurrent element are impacted by the grid-connected PV system. Therefore, in the fault analysis study and the protection schemes settings, this type of system should not be modeled as a conventional power generator.masters, M.Engr., Electrical and Computer Engineering -- University of Idaho - College of Graduate Studies, 2018-0
Exploring Temporal Phases of Wildfire Adaptation: Experiences Across Socially Diverse Communities
No full textThe increasing frequency and size of wildfire events across the United States and their subsequent impacts on populations living in fire-prone landscapes indicate an urgent need to strengthen community efforts to adapt to fire. Communities in the wildland-urban interface may take vastly different approaches to address wildfire risk, complicating the adoption and implementation of many policy and management efforts. Developing a stronger understanding of how varying community-wildfire interactions may change and evolve over time can offer insights about the enduring social legacies of wildfire risk and their implications for wildfire management. This dissertation presents three studies in four different communities across the Western United States designed to investigate social dimensions of wildfire before, during, and after wildfire events, including: (1) Community recovery and extra-local assistance after a large fire; (2) The influence of pre-fire and event-based cues on intended evacuation behavior; and (3) Support for regulatory approaches to wildfire risk reduction in two rural communities. I use a range of qualitative and quantitative methods to explore how communities can or are adapting to wildfire at different ‘phases’ in the duration of a wildfire’s lifespan. Each chapter concludes with a discussion of implications or recommendations for wildfire risk management in the wildland-urban interface. These efforts can inform proactive approaches to policy design and management implementation that can better support communities at different points in time and in different local contexts.doctoral, Ph.D., Natural Resources -- University of Idaho - College of Graduate Studies, 2018-1
Ethical Transformational Leadership in Public Administration
No full textThis study further develops the transformational leadership theory and ideals for public leadership with an ethical inclusion by testing whether this addition affects two important organizational outcomes, employee satisfaction and leadership effectiveness in federal agencies. The purpose is to delineate an exceptional model for public leadership. The analysis incorporates four ethics, termed by this exploration as public ethics, as a complementary addition to transformational leadership. Two components, transformational leadership (inspirational motivation, intellectual stimulation, and idealized influence) and individualized consideration, define transformational leadership. The findings suggest that both transformational leadership and public ethics positively relate to employee satisfaction and leadership effectiveness. Furthermore, the study finds that public ethics have a stronger positive relationship to employee satisfaction and leadership effectiveness than transformational leadership and individualized consideration, although transformational leadership better explains the variance in employee satisfaction and individualized consideration better explains leadership effectiveness than public ethics. In addition, the analysis portrays public leaders as low in transformational leadership and public ethics while high in individualized consideration behaviors. Thus, the study suggests that public leaders need to emphasize the development of transformational and ethical leaders to build a more satisfied workforce and effective public leader.doctoral, Ph.D., Political Science -- University of Idaho - College of Graduate Studies, 2018-0
The Effect of Different Management Factors on Health and Performance of Pre-weaned and Post-Weaned Dairy Calves
No full textABSTRACT The main purpose of the work described in this thesis is to identify management strategies for maximizing IgG levels in calves on modern dairies. It is well established that 25 to 35 % of dairy cows on US dairies must be replaced annually to maintain herd size and improve genetics (Harris and Shearer, 2005). The cost of raising dairy heifers increases if inadequate management results in a higher than normal morbidity and/or mortality. Colostrum management has a very large impact on dairy calf health due to the fact that calves are born without significant number of immunoglobulins (antibodies). The objectives of these researches were 1) determine the effect of adding a serum derived colostrum supplement to maternal colostrum and its effects on serum immunoglobulin concentration in calves, health and performance of pre-weaned and post-weaned dairy calves, 2) Determine the effect of quantity and frequency of colostrum feeding on serum immunoglobulin concentration, health parameters, and growth in Holstein calves, 3) Determine the correlation between total serum protein in calves and first lactation milk performance. Adding a supplement to maternal colostrum did not achieve any positive effect on performance and health parameters of dairy calves. In the second study results suggest that, feeding Holstein calves 2 separate feedings of maternal colostrum will improve passive transfer and might lead to some health benefits. The effect of colostrum feeding quantity and frequency on RS needs to be investigated further. In the third study results shows that, In the first lactation, calves that had TSP below 5.4 mg/d produced 10,551 ± 230 kg, those with TSP between 5.4 and 6.4 mg/dl produced 10,499 ± 229 kg, and those with TSP above 6.4 mg/dl produced 10,445 ± 230 kg. There was no relationship (P = 0.13) between TSP and future milk production.masters, M.S., Animal and Veterinary Science -- University of Idaho - College of Graduate Studies, 2018-0
Evaluating the Effects of Air Exposure on Salmonids
No full textFishing regulations are used by natural resource agencies to accomplish a variety of management objectives, including a focus on improving the quality of a fishery or maintaining the viability of a population. Catch-and-release regulations have largely been successful in reducing exploitation and increasing density and size structure of fish populations. In recent years, concerns have been raised regarding anglers exposing fish to air during catch-and-release angling. This thesis quantified how long anglers expose fish to air during catch-and-release angling, evaluated the effects of air exposure on the survival of Yellowstone Cutthroat Trout, Bull Trout, and Rainbow Trout, and evaluated the effect of air exposure on the fitness of Yellowstone Cutthroat Trout. Results of this study suggest that anglers typically do not expose fish to air long enough during catch-and-release angling to incur the negative effects associated with prolonged air exposure. Additionally, evaluation of the effects of air exposure on survival and fitness indicated that air exposure has no effect at up to 60 s of air exposure.masters, M.S., Natural Resources -- University of Idaho - College of Graduate Studies, 2018-0
Heat Flux at the Near-Surface and Atmosphere Boundary at Geothermal Areas: Development of Methods Used for Measurement and Quantification of the System
No full textEstimating the heat flux at the near-surface and atmospheric boundary in geothermal areas is a useful, yet difficult task. Through temperature measurements in the shallow subsurface, we can quantify the heat being transferred through soils, and many times the heat signature resulting from spatial measurements allows us to make suggestions about the system's flow and control paths. Despite the value in knowing this, through this study I have found that current methods used for measurement of soil temperatures may provide inaccurate readings if the tools used are made of a high thermal conductivity material, which in turn introduces error into the heat flux calculations. In this study, I use laboratory and field data to show that accurate shallow temperature gradients can be obtained using probes of low thermal conductivity material, these probes are described in detail. Additionally, I present a quantitative framework, which is currently lacking, for transient coupled land-air thermal interactions in geothermal systems.masters, M.S., Geology -- University of Idaho - College of Graduate Studies, 2018-0
Temporal Variations in Hotspot Volcanic Production Related to Interactions Between Upwelling Mantle Plumes and Phase Transitions
No full textObservations at numerous hotspots around the globe, such as Hawaii and Louisville, find periodic variations in volcanic production with time. For example, the volcanic production rate along the Hawaiian seamount chain varies from 0.05 to 0.25 km3 yr-1 at periods of ~15 Myr, while volcanic production rate along the Louisville seamount chain in the southern Pacific Ocean has consistently declined over the past ~40 Myr. One possible explanation for these variations is long-term interaction of upwelling mantle plumes with mantle phase transitions. While previous studies carefully quantify the initial interaction and subsequent penetration or inhibition of a plume as it encounters the 660 km phase boundary and traverses the transition zone, the long term interaction of plume upwelling and phase boundaries in the mantle is not well constrained. To assess the impact of plume-phase transition interaction on observed variability in hotspot volcanic output, I use the Advanced Solver for Problems in Earth’s ConvecTion (ASPECT) code to numerically simulate upwelling of an isolated plume under the Anelastic Liquid Approximation (ALA). I use a 2D annulus geometry with a 90° opening width and mantle thickness of 2855 km. Plume upwelling is initiated by imposing anomalously warm (∆T 550 K) temperatures across a zone 600 km wide centered at the base of the model. At the 660 km and 410 km depth mantle phase transitions I simulate changes in density, viscosity, and the release of latent heat. Models evolve for up to 400 Myr. To test the effect of differing mantle compositions, I vary the Clapeyron slopes from 0 to 4 MPa and -4 to 0 MPa at the 410 km and 660 km phase transitions, respectively. Similar to other studies, results show an initial flattening of the plume head at the 660 km transition before penetration and subsequent acceleration across the 410 km transition, coinciding with mild flattening of the 660 km, and deepening of the 410 km. At sufficiently low 660 km transition Clapeyron slopes (~-3.2 MPa K-1), secondary plumes form at a mid-mantle thermal boundary layer that forms as inhibited material spreads laterally underneath the transition. The spacing of these secondary plumes (~200-1200 km) is similar to surface observations (e.g., Iceland, East African Rift). By including imposed surface velocities (0-8 cm yr-1), volume flux variations are seen from plume conduit instabilities that form when the conduit tilts ~88º from vertical. These variations have a periodicity between ~4.1-37.9 Myr, which is similar to those seen at Hawaii and Iceland.masters, M.S., Geology -- University of Idaho - College of Graduate Studies, 2018-0
Live Load Distribution Factors of Rural Bridges Subjected to Farming Vehicles
No full textThe Pacific Northwest region has no data on the assessment of rural bridge design and safety subjected to \ac{fv} loading. This thesis examines how different types of \acp{fv} with different characteristics distribute their loads on bridges. Live load distribution factors for girders in short span bridges under the critical loading conditions have been determined. The selected bridges are representative of rural bridges in the region. The computer models have been verified using field data in order to explore a number of bridges under various \acp{fv}. It is concluded that some of the \acp{fv} resulted in loads on the girders greater than the design values obtained from the AASHTO LRFD specifications.masters, M.S., Civil Engineering -- University of Idaho - College of Graduate Studies, 2018-0
Revision of the Motivational Correlates and Athletes’ Perceptions of Coach-Created Motivational Climate: An Adult American Sport Sample
No full textMotivational Climate (MC) is an important situational factor influencing participation in sport that is largely coach-created (Balaguer, Duda, & Crespo, 1999; Duda & Balaguer, 2007; Smith, Smoll, & Cumming, 2007). Two types of MC have been identified, task/mastery or ego/performance, with MC reflecting athletes’ perceptions of the sport environment in which they practice and compete (Ntoumanis & Biddle, 1999). Although limited research has been conducted on how coaches can promote a particular type of competitive climate, achievement goal theory (AGT) has hypothesized how either type of MC can be created over time through task- or ego-focused goals (Ames, 1992; Nicholls, 1989). To date, research investigating how coach-created MC environment is perceived by athletes has been somewhat limited, particularly how this MC perception is affected other motivational correlates in sport (i.e., perfectionism, goal setting styles, and mindsets). The purpose of this dissertation was twofold: (a) to examine the Empowering-Disempowering Motivational Climate Questionnaire – Coach Version that was developed for children and adolescents in the United Kingdom in order to see how well the instrument fits an American collegiate and professional sport population, and (b) in the event that the instrument does not have acceptable fit indices, investigate whether the instrument can be revised so fit is acceptable and provide preliminary construct validity for the revised instrument. The objective of Study 1 was to validate the EDMCQ-C scale using an American population of adult athletes. However, the EDMCQ-C did not provide acceptable fit indices for an adult population, prompting a revised EDMCQ to be developed for adult American athletes labeled the EDMCQ-Adult Collegiate Sample (EDMCQ-ACS) that had three subscales (i.e. task involvement, ego involvement and controlling coaching) and demonstrated strong CFA fit indices. Study 2 used cluster analysis of the three MC subscales to create four MC profile groups, and then multivariate analysis of variance (MANOVA) to identify differences between profile groups on motivational correlate variables (i.e., mindsets, perfectionism, and GSSs subscales). Finally, canonical correlation analysis was used to examine the relationships between the three MC subscales in one variable set and separate analyses examining their relationship with: (a) mindsets, (b) perfectionism, (c) goal setting styles, and (d) all motivational correlate variables as one set. Results showed support for the emerging hypotheses whereby empowering motivational climates correlated significantly with functional psychological variables. Further support was shown whereby disempowering motivational climates correlated with dysfunctional psychological variables. Results were discussed in light of limitations and future directions.doctoral, Ph.D., Movement & Leisure Sciences -- University of Idaho - College of Graduate Studies, 2018-1