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This focused ethnography of Appalachian Trail (AT) long-distance hikers explored the situated and informal nature of individual knowledge construction as mediated through a community of practice. Unlike place-based or cyber-bound communities, the ever-changing membership and location dynamics of AT hikers offered a unique and researchable community for study. The complex and understudied sensemaking trajectories of individuals moving through this mobile community were investigated over three years through in-depth interviews and participant observations. Inductive analysis of expert and novice stories illuminated experiential patterns and collective traditions that comprise the AT learning culture. In contrast to traditional approaches to knowledge and skill acquisition, this study found socio-reflective exchanges, nested in hiking pods, to be critical sites for cognitive modeling and informal scaffolding between experts and novices. The situated encounters and developmental support of these nomadic pods were found to facilitate individuals' construction of community-based knowledge. / Ph. D.

The Federal Aviation Administration (FAA) has been modernizing the United States' air transportation system within a series of initiatives called the Next Generation Air Transportation System (NextGen). The goal of NextGen is to increase the safety, efficiency, capacity, predictability, and resiliency of American Air Traffic Control (ATC) by implementing satellite-based communication, and navigation systems. Because of the vast oceanic areas controlled by Oakland, New York, and Anchorage air traffic control centers, improving oceanic operations is significant for the United States. According to the FAA, oceanic flights generate 31% of passenger revenue and 40% of cargo revenue in U.S.-controlled airspace. New NextGen procedures offer the opportunity for aircraft to save fuel consumption by allowing oceanic flights to fly at more efficient routes and flight levels. This dissertation investigates three areas to improve flight operations over oceanic airspace. The first area studies the operational benefits of providing satellite-based meteorological information to aircraft operating in remote and oceanic airspace. This research effort uses two approaches as follows: 1) statistical flight analysis, and 2) simulation-based analysis. The second area provides an optimization technique to improve the current procedures for assigning flights to the Organized Track System (OTS) in the Atlantic Ocean based on the Collaborative Decision Making (CDM) concept. The third area investigates the potential savings of "In-Trail Procedure" (ITP) as one of the advanced surveillance operations in the Pacific and Atlantic oceanic airspace. To quantify the operational benefits of the proposed procedures, a fast-time simulation tool, the Global Oceanic (GO) model, is developed and employed. The GO model is a microscopic flight simulation tool that has been developing by the Air Transportation Systems Laboratory at Virginia Tech offering realistic and inexpensive evaluations of novel technologies and procedures to improve flight operations over global oceanic airspace. the results of these studies are analyzed in terms of fuel consumption, travel distance, travel time, level of service, and potential air traffic controllers' workload. / Doctor of Philosophy / The economic growth and social connectivity of nations are highly correlated to effective and efficient air transportation systems. The Federal Aviation Administration (FAA) has initiated a program to modernize America's air transportation system and make flight operations safer, and more efficient. This program is called the Next Generation Air Transportation System (NextGen) and its goal is transforming the communication and navigation technologies to satellite-based systems. Improving oceanic flights is one of the main concerns of the NextGen program since the United States controls massive oceanic areas in the Atlantic and the Pacific Ocean. The FAA needs to evaluate the benefits and costs of advanced technologies and procedures to justify the NextGen initiatives. The FAA has employed computer simulation tools to support decisions for future infrastructure investments and encourage airlines to equip their aircraft with more advanced avionics. The Global Oceanic (GO) model is a microscopic flight simulation tool developed jointly by the Air Transportation Systems Laboratory at Virginia Tech and the FAA providing quick, realistic, and inexpensive evaluations of advanced procedures to improve flight operations over oceans. This dissertation investigates the operational benefit of three advanced procedures using the GO model. The areas to improve flight operations over oceanic airspace are as follows: 1) operational benefits of providing satellite-based meteorological information to aircraft operating in remote and oceanic airspace, 2) operational benefits of an optimization technique for flight assignments to the Organized Track System (OTS) in the Atlantic Ocean, 3) operational benefits of "In-Trail Procedure" (ITP) as one of the advanced surveillance operations in the Pacific and Atlantic oceanic airspace. These studies quantify the potential savings of these procedures in terms of reducing fuel consumption, travel distance, travel time, greenhouse gas emissions, and potential air traffic controllers' workload.

Mapping quantitative trait loci in outbred populations is important since development of inbred lines in livestock species is usually not feasible. Traditional genetic mapping methods, such as Least Squares and Maximum Likelihood, cannot fully accommodate complex pedigree structures, and more sophisticated methods such as Bayesian analysis are very demanding computationally. In this thesis, an alternative approach based on a Residual Maximum Likelihood method for estimation of position and variance of one or two linked QTLs and of additive polygenic and residual variances is presented. The method is based on a mixed linear model including polygenic and random QTL allelic effects. The variance-covariance matrix of QTL allelic effects and its inverse is computed conditional on incomplete information from multiple linked markers. The method is implemented using interval mapping and a derivative-free algorithm, where the required coefficient matrix of the Mixed Model Equations is derived from a Reduced Animal Model. simulation studies based on a granddaughter design with 2000 sons, 20 sires and 9 ancestors were performed to evaluate parameter estimation and power of QTL detection. Daughter Yield Deviations of sons were simulated under three QTL models, a biallelic, a multiallelic (10 alleles), and a normal-effects model. A linkage group of five or nine markers located on the same chromosome was assumed, and genotypes were available on sons, sires and ancestors. Likelihood ratio statistics were used to test for the presence of one or two linked QTLs. Parameters were estimated quite accurately for all three QTL models, showing that the method is robust to the number of alleles at the QTL. The effect of considering or ignoring relationships in the analyses did not have a major impact on parameter estimates but reduced the power of QTL detection. In general, power tended to decrease as the number of sons per sire, QTL contribution to additive genetic variance, or distance between QTLs was reduced. The method allowed for detection of a single QTL explaining 25% of the additive genetic variance, and for detection of two QTLs when jointly they accounted for 50% or 12.5% of the additive genetic variance. Although the REML analysis is an approximate method incorporating an expected covariance matrix of the QTL effects conditional on marker information, it is a computationally less expensive alternative to Bayesian analysis for accounting for the distribution of marker-QTL genotypes given marker and phenotypic information. For the designs studied, parameters were estimated accurately and QTLs mapped with satisfactory power. / Ph. D.

Globally, wind power is leading the renewable energy revolution. While carbon neutral and cost-effective, wind energy infrastructure is immobile and has the potential to profoundly change land use and the visible landscape. As wind technology takes its place as a key contributor to the US energy grid, it becomes clear that these types of projects will come into greater contact with areas occupied by humans, and eventually with wilderness and other more natural areas. This increased visibility and close proximity necessitates the development of future wind farm sites that afford opportunities for auxiliary uses while maintaining their intrinsic value as energy producers. In short, it is important for wind farms to be versatile because land is a finite resource and because over time, increasing numbers of these sites will occupy our landscapes. In the Eastern US, the majority of onshore wind resources suitable for energy development are found along ridge lines in the Appalachian mountains. These mountains are ancient focal points in the landscape, and subsequently host myriad sites of historic, recreational, and scenic significance. In the future, these windswept ridges will likely become targets for wind energy development. This thesis demonstrates a methodology for the thoughtful siting and design of future wind projects in the Appalachian mountains. Opportunities for offsite views, diversified trail experiences, and planned timber harvests are realized by locating a seven-turbine wind park adjacent to the Appalachian Trail in Cherokee National Forest in Carter county, Tennessee. The proposed wind park demonstrates the sound possibility of thoughtfully integrating wind infrastructure along Appalachian ridges in conjunction with forestry and recreation opportunities, such as hiking and camping. The design is a wind park rather than a wind farm because in addition to its inherent function as a production landscape, it is also a place that is open to the general public for recreational use. / Master of Landscape Architecture

Architecture and music share intrinsic meanings generated by a constant stream of metaphors which are forms of poetic transformations. This thesis sought to challenge the present way an architect-musician makes drawings through the exploration of multimedia possibilities at hand. The drawings are composed using Macromedia Flash MX. OPEN HOMEPAGE.EXE To download flash player, click here: <a href="http://www.macromedia.com/shockwave/download/download.cgi?P1_Prod_Version=ShockwaveFlash"> Download flash Player</a> / Master of Architecture

Hiking is a widely-used term used differently by different people, and technology has an increasing role in the hikes that people take. Given the tremendous growth in technology capabilities for fitness, navigation, and communication, the breadth of devices and applications has expanded. Use of technology differs based on not only individuals but also the kinds of tasks performed. This research seeks to understand the different perspectives of the hikers and the technology they carry with them on the trail through a survey, analysis, and persona creation. 40 self-described hikers participated in a survey that asked about demographic data, hiking preferences, and would-you-rather preferences asking participants to choose between envisioned hiking and technology scenarios. The collected data were clustered into 6 clusters using K-Mode clustering, and descriptive analysis identified unique characteristics for each cluster. Five personas were crafted using the identified characteristics based on the analysis, taking into account the correlation between hiking preference and age, preferred activities and motivation, and maximum expenses they spend on the tech they carry. These personas seek to act as a guide to those who purchase, design and use hiking related products for both commercial and research purposes. / Master of Science