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The nature of martian micrometeorites (MMs) was investigated in this thesis through micro-analysis of terrestrial MMs and computational and experimental simulations of atmospheric entry heating. The biases in the Larkman Nunatak micrometeorite collection revealed in this study (Chapter 3) are attributed to the strong winnowing effects associated with sediment transport by aeolian processes. The weathering features observed in these micrometeorites are related to interaction with transient water. Sediment transport on Mars is dominated by aeolian processes, thus accumulations are likely to be similar to wind driven collections on Earth. However, their weathering state is expected to differ from terrestrial micrometeorites owing to the lack of water and much longer accumulation periods and is instead thought to be dominated by perchlorate induced oxidation. Computational simulations of atmospheric entry (Chapter 4) suggest much greater quantities of large, low temperature micrometeorites reaching the martian surface. The lower temperatures and larger particles surviving on Mars are likely to aid in the preservation of micrometeorite derived organic material with large portions of the micrometeorite flux expected to remain below the sublimation temperature of some organic compounds and larger particles allowing thermal gradients to form within particles. Experimental simulations (Chapter 5) indicate several differences between terrestrial and martian particles. Iron oxide phases were lacking in the martian particles including a magnetite rim, which is observed in the severely heated terrestrial particles. Additionally, sulphur and phosphorus are preserved in much greater quantities and in reduced forms in the martian particles. Raman spectroscopy also revealed that micrometeorite derived organic material on Earth experience greater evolution through the expansion of sp2 cluster diameter and growth of aromatic ring structures. Most of these features can be attributed to oxidative processes. Thus, atmospheric composition is thought to be a controlling factor in the nature micrometeorite derived organic material reaching a planetary surface.

Objects are characterised by their properties. If an object is a red postbox, then it has the property of being red, and the property of being a postbox. This thesis is an attack on a particular view of the metaphysics of properties, according to which some properties are privileged over others. The most well-known theories of privileged properties are Armstrong’s theory of sparse immanent universals (1979b) and Lewis’ natural properties (1983). According to their supporters, only privileged properties perform certain jobs, such as featuring in laws of nature, or grounding similarity between objects. Metaphysical posits are theoretically virtuous if they can account for a range of different phenomena in a relatively parsimonious manner. The ability of privileged properties to perform a range of worthwhile ‘work’, therefore, is what justifies a belief in them. The conclusion I reach is that a single group of properties is not capable of satisfying the key roles commonly attributed to the privileged properties. Without satisfying these roles in concert, a belief in mainstream versions of privileged properties is not justified. The first part of this thesis is devoted to an explication of privilege and the roles which privileged properties are taken to perform. I conclude that three roles in particular, Supervenience, Similarity and Magnetism are key roles for mainstream theories of privilege. In part two, I show that the properties which satisfy the Supervenience role are not the same as those which satisfy the Similarity and Magnetism roles. In the final chapter of this thesis I discuss the implications of my findings for support for theories of privilege.

The railway industry is largely neglected by current sociology, yet promising topics for sociological investigation abound: the organisational structure of the railway industry; risk management and the reaction to rail accidents in a “risk society”; the development and introduction of new rail technologies; the problem of rail project management (e.g. the troubles of the massive west coast mainline renewal project); and so on. Despite this there is almost no “railway sociology” in the UK, a striking omission both in itself and in comparison with the wealth of work produced by the railway historian. Our of the many possible research avenues, “railway maintenance” was chosen to be analysed sociologically. The project was conceived in the aftermath of the fatal accident at Welham Curve near Hatfield, England in October, 2000. A fault directly related to the wheel/rail interface cause the rail to break. Though a technical failure it transpired that issues connected to the organisational culture of the industry – such as the management and distribution of rail maintenance knowledge – were of direct consequence. How leaders of an organisation perceive its objectives, and how employee roles, tasks, and specialisms are structured can have a huge impact on how an individual or a group conducts their work. These matters become intertwined and workplace cultures can develop and become embedded which can affect a group’s worldview and language codes, which can, in turn, impact on inter-organisational communication and interaction. The effects this has on technical decision-making which requires tacit knowledge is substantial; at all levels in an organisation the nature of choice is effectively a product of the environment within which it is made.

Since being introduced into classrooms in the late 1990s, online instruction has grown substantially both in student enrollment and the number of programs offered at state, district, and multi-district levels. Although having been applied liberally to all core subjects and many supplemental subjects, online instruction has yet to be utilized extensively in the musical arts. Courses in music performance present a unique set of technological and logistical challenges when adapted to an online setting. Nevertheless, private music teachers have utilized Internet resources extensively. Similar techniques applied to public school music programs, however, have yet to be explored thoroughly. Utilizing a combination of asynchronous instruction and synchronous instruction for teaching online music performance courses offers a potential for study and development. The purpose of this study was to establish the feasibility of an online music performance course that included both asynchronous and synchronous instruction. An approach that utilized both a multimedia blog format and real-time video instruction was developed, implemented, and delivered to a limited group of trombone students as a pilot study. Nine students participated in online trombone lessons that focused primarily upon the development of performance fundamentals. The delivery of content was assessed to determine a feasible format for music performance instruction in an online setting. Although typical technological shortcomings were experienced during instructional settings, students were able to identify, explain, and apply concepts gleaned from the blog and real-time video lessons. Internet-based resources have been applied to independent and collegiate music performance instruction; pedagogical approaches, however, have not been developed for use in secondary level online learning programs. Consequently, online music performance instruction has not evolved as rapidly as online instruction of core academic subjects. As technological advances become available, the possibility for delivering online instruction in areas of the performing arts, and especially in music performance, becomes more feasible and likely will be integrated into the curricula of many online learning programs. Until such time, the implementation of viable online instructional models is essential for the development of traditional music performance courses. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

The power system is comprised of thousands of lines, generation sources, transformers, and other equipment responsible for servicing millions of customers. Such a complex apparatus requires constant monitoring and protection schemes capable of keeping the system operational, reliable, and resilient. To achieve these goals, measurement is a critical role in the continued functionality of the power system. However, measurement devices are never completely reliable, and are susceptible to inherent irregularities; imparting potentially misleading distortions on measurements containing high-frequency components. This dissertation analyzes some of these effects, as well as the way they may impact certain applications in the grid that utilize these kinds of measurements. This dissertation first presents background on existing measurement technologies currently in use in the power grid, with extra emphasis placed on point-on-wave (PoW) sensors, those designed to capture oscillographic records of voltage and current signals. Next, a waveform “playback” system, developed at Oak Ridge National Laboratory’s Distributed Energy Communications \& Control (DECC) laboratory was used for comparisons between various line-post-monitor PoW sensors when subjected to different high-frequency current disturbances. Each of the three sensors exhibited unique quirks in these spectral regions, both in terms of harmonic magnitude and phase angle. A goodness-of-fit metric for comparing an ideal reference sensor with the test sensors was adopted from the literature and showed the extremes to which two test sensors vastly under performed when compared to the third. The subsequent chapter analyzes these behaviors under a statistical lens, using kernel density estimation to fit probability density functions (PDFs) to error distributions at specific harmonic frequencies resulting from sensor frequency response distortions. The remaining two chapters of the dissertation are concerned with resultant effects on applications that require high-frequency transient data. First, a detection algorithm is presented, and its performance when subjected to statistical errors inherent in these sensors is quantified. The dissertation culminates with a study on an artificial intelligence (AI) technique for estimating the location of capacitor switching transients, as well as learning prediction intervals that indicate the level of uncertainty present in the data caused by sensor frequency response irregularities.

Power utilities employ "smart'' field devices capable of digitally recording electrical waveforms. The relationship between events and their recorded waveforms can be exploited for characterization of the power grid’s state over any period of time and facilitating the impact electrical disturbances have on equipment, subsystems, and systems. Over a period of one month, these devices record approximately 2,000 electrical disturbance waveforms. Currently, analysis of these waveforms is conducted using by-hand approaches; thus, severely limiting the analysis to roughly 2%. The analysis is done hours to days after the events occurred, which negates informed, timely corrective actions. This document presents an automated hierarchical approach capable of identifying specific events using the electrical disturbance waveforms stored using COMmon format for TRAnsient Data Exchange (COMTRADE) files. The developed approach processes a single file in 1.8 seconds and has demonstrated successful identification of 140 events with a success rate of 91%.

There is an ongoing crisis among the Native American male population as they seek higher educational attainment. Currently, Native American males are experiencing such low numbers of higher educational attainment that their reporting they could be considered non-existent. This study identifies the primary motives of Native American male students who have successfully reached educational degree attainment. Understanding and discovering the major barriers in higher educational attainment among Native American male students, their management practices and the strategies that contributed to successful completion of a college degree program is a secondary aim. Study finding indicate the primary motive of Native American male students to earn college degrees is to obtain knowledge and skill sets that would allow them to engage in work that will result in positive outcomes within their tribal communities. The findings also identified major barriers to educational attainment which were lack of support within higher educational institutions, cost associated attendance and living expenses, and being away from their communities. In addition, the inability to ask for and receive the help necessary to move forward in the educational process was noted. The findings highlight the need for and significance of asking for help, traveling home often to participate in ceremonies and tribal gatherings, finding and building support groups within the university setting, and religious practices that contributed to the success and excellence of the participants to reach degree attainment.

The Southern Annular Mode (SAM) has long been acknowledged as the dominant mode of atmospheric circulation variability in the mid- and high latitudes of the Southern Hemisphere (SH). The largest mode of global atmospheric circulation variability on interannual timescales is the El Niño-Southern Oscillation (ENSO). Studies over the last decade have shown that SAM reinforces circulation anomalies caused by ENSO variability in the high-southern latitudes through transient eddy processes and significant changes to the position and strength of the jet streams. Research on ENSO flavors has recently emerged as well, as scientists use the location of the tropical Pacific sea surface temperature (SST) anomalies to classify ENSO events as Eastern Pacific (EP) or Central Pacific (CP). This study combines previous research on the ENSO-SAM interaction with ENSO flavors to document changes to atmospheric circulation in the SH, particularly at high latitudes, which have received little attention in the discussion of ENSO flavors. A series of global climate model simulations using the National Center for Atmospheric Research Community Atmosphere Model (CAM) version 4 strongly confirm SAM's active modulation of the ENSO teleconnection to Antarctica regardless of ENSO flavor. A comparison between idealized simulations of strong CP and EP events verifies previous research showing increased blocking over the Australian continent and a southward shift in the sub-tropical jet (STJ) across the eastern Pacific basin during CP events. More importantly for the high-southern latitudes, a westward shift in the upper- level divergence in the tropical Pacific causes the Pacific-South American (PSA) stationary wave pattern to shift toward the west as well. These changes to the Rossby wave source region lead to the downstream effects including decreased blocking in the Amundsen-Bellingshausen Seas region as anticyclonic flow becomes established in the South Central Pacific. The atmospheric circulation changes lead to modifications of heat and momentum fluxes due to stationary eddies across the South Pacific and weaken the ENSO-Antarctic Dipole relationship. CAM demonstrates these changes to atmospheric circulation more robustly when results are filtered for the observed SAM phase, proving that high-latitude atmospheric circulation variability in the South Pacific is induced by both tropical and high-latitude forcing.

In continuing the evaluation of Polar WRF 3.1.1, this high resolution mesoscale model for regional scale studies is used to simulate Arctic conditions for the year December 2006 – November 2007. The goal is to examine key characteristics of weather patterns, comparing model output to documented reanalyses and observational data sets of surface and upper level observations. The domain mirrors that of the Arctic System Reanalysis (ASR), an assimilation of model results, field observations, and satellite observations of the Arctic being conducted partly by the Byrd Polar Research Center at The Ohio State University. Included in this area of study is the Arctic Basin, the river drainage areas of the subarctic, as well as the surrounding mid-latitudes in the Northern Hemisphere. This simulation takes advantage of previous polar modifications to mesoscale modeling, including updates to snow pack treatment, radiative transfer properties, and fractional sea ice implementation. A key development in this Polar WRF study is the extension of the seasonal progression of sea ice albedo to the entire domain. The boundary conditions are specified by the NCEP Global Forecast System (GFS) Final global gridded analysis archive (FNL); a 1deg x 1deg global grid updated every 6 hours. The simulations are performed in 48 hour increments initialized daily at 0000UTC, with the first 24 hours discarded for model spin-up. Overall, the results of the surface and upper air analysis are promising. Polar WRF predicted values of surface and sea level pressure are excellent, with good correlations between model and observations. In addition, Polar WRF 2 m temperature and 2m dewpoint show good skill and small biases. Likewise, the modeled upper air variables (temperature, geopotential height, and wind speed) outperform the surface analysis. In addition to the standard meteorological variable analysis, the hydrologic cycle is evaluated. Precipitation, when considering locations in open, flat areas away from high terrain is modeled well. Additionally, an investigation into the precipitation basins for Arctic rivers shows these areas have little bias when compared to observations. There are deficiencies identified with this current model configuration however. Most importantly, an evaluation of cloud fraction reveals that the summertime Arctic stratus clouds are severely under predicted, which leads to precipitation deficits in the Arctic as well as an amplified diurnal temperature cycle. While the modeled polar region suffers from too little precipitation, the mid-latitudes demonstrate a surplus owing largely to the convective parameterization. However, these limitations provide a benchmark from which to improve the model and guidance for further development for Polar WRF’s use as ASR’s primary model.

Hawai’i holds a somewhat nebulous place in American History. While it easily fits in the dominant narrative surrounding the Spanish American War of 1898 and World War II, Hawai’i rarely factors into other major historical fields, often making a brief cameo appearance when it does. Because the state is geographically placed at the western extreme of America, one supposes that western historians would gladly accept the task of chronicling Hawaiian history; yet, even academics in this field hesitate to embrace the region. In fact, some scholars who study the American West completely dismiss the notion of including the Hawaiian Islands. General American history textbooks reflect academics’ uncertainty towards including the islands in the greater American narrative as they rarely mention Hawaiian events. Comparing Hawai’i with the continental territories, Native American policy, American insular colonies, and U.S. imperialism, however, quickly dispels the notion that Hawai’i lies outside the American West. In fact, it holds a very important role in American history as the transitional zone between the older expansionist American imperialism and a newer form of American colonialism. Moreover, incorporating Hawaiian history into western regional studies forces scholars in the field to rethink existing paradigms. At the present, western historians view the West as a place lying roughly between the Mississippi River and the Pacific coast. Including the Hawaiian Islands, however, forces them to refine their rigid political definition of the West to allow for more fluid boundaries. This dissertation argues that including Hawai’i forces scholars to redefine the region as those incorporated territories throughout western North America and the Pacific Ocean which the United States conquered, subdued, annexed, and admitted into the Union. Moreover, it is a place in which American imperialism reshaped, and continues to shape, all facets of human life and the environment.