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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Digital Trails

Morris, Scott Howard January 2010 (has links)
May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view. May your mountains rise into and above the clouds. Edward Abbey The digital representation of trails is a relatively new concept. Only in the last decade, with increasing adoption and accuracy of GPS technology, have large quantities of reliable data become a reality. However, the development of algorithms specific to processing digital trails has not had much attention. This dissertation presents a set of methods for collecting, improving and processing digital trails, laying the ground work for the science of trails.We first present a solution to the GPS-network problem, which determines the salient trails and structure of a trail network from a set of GPS tracklogs. This method has received significant attention from the industry and online GPS sharing sites, since it provides the basis for forming a digital library of trails from user submitted GPS tracks.A set of tracks through a GPS trail network further presents the opportunity to model and understand trail user behavior. Trail user models are useful to land managers faced with difficult management decisions. We present the K-history model, a probabilistic method for understanding and simulating trail user decisions based on GPS data. We use the K-history model to evaluate current simulation techniques and show how optimizing the number of historical decisions can lead to better predictive power.With collections of GPS trail data we can begin to learn what trails look like in aerial images. We present a statistical learning approach for automatically extracting trail data from aerial imagery, using GPS data to train our model. While the problem of recognizing relatively straight and well defined roads has been well studied in the literature, the more difficult problem of extracting trails has received no attention. We extensively test our method on a 2,500 mile trail, showing promise for obtaining digital trail data without the use of GPS.These methods present further possibilities for the study of trails and trail user behavior, resulting in increased opportunity for the outdoors lover, and more informed management of our natural areas.
62

Trail-use conflict on public lands among selected user groups : towards a framework for managing appropriate activities

Danyo, Stephen John 12 1900 (has links)
No description available.
63

Predicted and measured arrival rates of meteors over forward-scatter links.

Mawrey, Robert Stanley. January 1991 (has links)
Investigations into currently accepted methods of modelling variations in the arrival rate of meteors over forward-scatter meteor links have revealed some shortcomings. In these investigations, particular emphasis is placed on the work of Rudie due to its current acceptance in the literature. The non-uniform radiant distribution of meteors measured by Davies and modelled by Rudie, is critically examined and predictions using these models are compared with measured results taken over two forward-scatter links in the Southern Hemisphere. A new, alternative method of including the effect of non-uniform radiant distributions on the predicted arrival rate of meteors is given. The method used by Rudie to model Davies' measured radiant distribution is shown to be unnecessarily complicated and a simpler alternative is given. Furthermore, Rudie's distribution is shown not to be derived from a particular set of Davies' results as implied by Rudie. Other non-uniform distributions of meteors are also investigated. Comparisons between monthly-averaged daily cycles of measured and predicted arrival rates of meteors for a midpath and an endpath meteor link are used to reveal the validity and limitations of the published distributions. A new graphical method is used to aid in determining the validity and limitations of the non-uniform distributions. Discrepancies in the published predicted and measured annual variations in the arrival rate of meteors are investigated. Contrary to recently published information, predicted annual variations in the arrival rate of meteors for meteor radiants close to the ecliptic are shown to be comparable to measured results. / Thesis (Ph.D.)-University of Natal, Durban, 1991.
64

A practical investigation of meteor-burst communications.

Melville, Stuart William. January 1991 (has links)
This study considers the meteor-burst communication (MBC) environment at three levels. At the lowest level, the trails themselves are studied and analysed. Then individual links are studied in order to determine the data throughput and wait time that might be expected at various data rates. Finally, at the top level, MBC networks are studied in order to provide information on the effects of routing strategies, topologies, and connectivity in such networks. A significant amount of theoretical work has been done in the classification of meteor trails, and the analysis of the throughput potential of the channel. At the same time the issues of wait time on MBC links, and MBC network strategies, have been largely ignored. The work presented here is based on data captured on actual monitoring links, and is intended to provide both an observational comparison to theoretical predictions in the well-researched areas, and a source of base information for the others. Chapter 1 of this thesis gives an overview of the field of meteor-burst communications. Prior work in the field is discussed, as are the advantages and disadvantages of the channel, and current application areas. Chapter 2 describes work done on the classification of observed meteor trails into distinctive 'families'. The rule-based system designed for this task is discussed as well as the eventual classification schema produced, which is far more comprehensive and consistent than previously proposed schemas. Chapter 3 deals with the throughput potential of the channel, based on the observed trails. A comparison to predicted results, both as regards fixed and adaptive data-rates, is made with some notable differences between predicted v results and observed results highlighted. The trail families with the largest contribution to the throughput capacity of the channel are identified. Chapter 4 deals with wait time in meteor-burst communications. The data rates at which wait time is minimised in the links used are found, and compared to the rates at which throughput was optimised. These are found to be very different, as indeed are the contributions of the various trail families at these rates. Chapter 5 describes a software system designed to analyse the effect of routing strategies in MBC networks, and presents initial results derived from this system. Certain features of the channel, in particular its sporadic nature, are shown to have significant effects on network performance. Chapter 6 continues the presentation of network results, specifically concentrating on the effect of topologies and connectivity within MBC networks. Chapter 7 concludes the thesis, highlighting suggested areas for further research as well as summarising the more important results presented. / Thesis (Ph.D.)-University of Natal, Durban, 1991.
65

VALUES IN PLACE: INTERSECTING VALUES IN RAILS TO TRAILS LANDSCAPES

Brownell, Lisa Rainey 01 January 2011 (has links)
This dissertation is a study of the values and meanings people attach to places and why exploring those values is important in trails and historic preservation planning. From a foundation in critical humanistic geography and values based preservation literatures, the dissertation examines three rails to trails projects as case studies. Primary research questions include: how does a landscape become valued, devalued, and/or revalued through time? In what ways do different values of different people or groups intersect in rails to trails landscapes and how do they shape the landscape? How do historic values intersect with economic, social, political, and other values as these relate to landscape preservation? A subset of questions deals with the interactions between trails, historic preservation, and geography. What common ground do these three areas already share and what is the potential for further connections between and through them? The project contributes to the geographical tradition of interpreting ordinary landscapes but also works towards bringing together the common ground of three disparate endeavors: cultural geography, historic preservation, and trails planning around the theme of “values in place.”
66

Birding Trail Development from a Tourism Planning Perspective

Vas, Krisztian January 2012 (has links)
As bird-watching gains popularity, there have been various techniques utilized by tourism planners to attract birdwatchers. One method of drawing birders to a specific region is through the development of a birding trail. Although there are many birding trails with varying levels of success, there was little research as to how birding trails should be designed, implemented and managed. Perhaps, a new and viable approach to birding trail development would be to plan them as tourism product clubs. A product club is an association of tourism service providers working together to deliver an integrated service. Product clubs have been successfully implemented in Barbados with golf tourism and in Spain with winery tourism. However, the concept of a product club has never been applied to bird-watching tourism. Therefore, this research tested the idea of utilizing the product club concept for bird-watching tourism. The methodology had three separate phases. Phase one involved interviewing officials of existing tourism trails, to see how they planned and managed their trails. These interviews illustrated how and what is involved with tourism trail planning and management. Phase two involved the choice of a case study location, the County of Essex and Chatham-Kent in Ontario. Phase three was planning the trail by forming an Advisory Committee consisting of key industry, non-government and government stakeholders. The Advisory Committee assisted with the following key decisions: trail size and scope, selection of birding sites, choosing accessory tourism service institutions, developing a product club oversight organization, marketing the product club, and the management, evaluation and monitoring of the trail. The thesis provides recommendations that can be used to implement a birding trail as a tourism product club. The research findings concluded that a birding trail can be planned and managed as tourism product clubs.
67

Biophysical impacts and psychosocial experiences associated with use of selected long-distance walking tracks within the Wet Tropics region of North Queensland, Australia /

Young, Nigel Gordon Ryan. January 2006 (has links)
Thesis (Ph.D.) - James Cook University, 2006. / Typescript (photocopy) Bibliography: leaves 347-371.
68

Soil erosion and vegetation loss accelerated by visitor use of Paradise Meadows, Mount Rainier National Park /

Fritzke, Susan L. January 1992 (has links)
Thesis (M.S.)--Oregon State University, 1992. / Typescript (photocopy). Includes bibliographical references (leaves 51-56). Also available via the World Wide Web.
69

Planning and design guidelines for accommodating non-motorized transportation in suburban office parks

Bryant, Keith B., January 1900 (has links)
Thesis (M.S.)--West Virginia University, 2005 / Title from document title page. Document formatted into pages; contains vii, 129 p. : ill. (some col.), maps. Vita. Includes abstract. Includes bibliographical references.
70

Wanchai Gap Road revitalization

Leung, Shun-cheung, Xylem. January 2001 (has links)
Thesis (M.L.A.)--University of Hong Kong, 2001. / Includes bibliographical references. Also available in print.

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