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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.
81

A new data structure and algorithm for spatial network representation.

January 2003 (has links)
by Fung Tze Wa. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 92-96). / Abstracts in English and Chinese. / Abstract in English --- p.i / Abstract in Chinese --- p.ii / Acknowledgements --- p.iii / Table of Contents --- p.iv-vi / List of Figures --- p.vii-ix / List of Tables --- p.x / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- Introduction --- p.1 / Chapter 1.2 --- Motivation --- p.3 / Chapter 1.3 --- Purposes of this Research --- p.6 / Chapter 1.4 --- Contribution of this Research --- p.7 / Chapter 1.5 --- Outline of the Thesis --- p.9 / Chapter Chapter 2 --- Literature Review And Research Issues / Chapter 2.1 --- Introduction --- p.11 / Chapter 2.2 --- Spatial Access Methods --- p.14 / Chapter 2.2.1 --- R-Tree --- p.15 / Chapter 2.2.2 --- R*-Tree --- p.19 / Chapter 2.2.3 --- R+-Tree --- p.21 / Chapter 2.3 --- Spatial Network Analysis --- p.22 / Chapter 2.4 --- Nearest Neighbor Queries --- p.23 / Chapter 2.5 --- Summary --- p.25 / Chapter Chapter 3 --- Data Preparation / Chapter 3.1 --- "Introduction (XML, GML), XML indexing" --- p.26 / Chapter 3.2 --- Spatial data from Lands Department --- p.31 / Chapter 3.3 --- Graph representation for Road Network data --- p.32 / Chapter 3.4 --- Summary --- p.35 / Chapter Chapter 4 --- XML Indexing for Spatial Data / Chapter 4.1 --- Introduction --- p.36 / Chapter 4.2 --- STR Packed R-Tree --- p.38 / Chapter 4.2.1 --- Implementation --- p.39 / Chapter 4.2.2 --- Experimental Result --- p.41 / Chapter 4.3 --- Summary --- p.48 / Chapter Chapter 5 --- Spatial Network / Chapter 5.1 --- Introduction --- p.50 / Chapter 5.2 --- CCAM: Connectivity-Clustered Access Method --- p.53 / Chapter 5.3 --- Shortest Path in Spatial Network --- p.56 / Chapter 5.4 --- A New Algorithm Specially for Partitioning /Clustering Network --- p.63 / Chapter 5.5 --- A New Simple heuristic for Shortest Path Problem for Spatial Network --- p.70 / Chapter 5.6 --- Summary --- p.74 / Chapter Chapter 6 --- Nearest Neighbor Queries / Chapter 6.1 --- Introduction --- p.76 / Chapter 6.2 --- Modified Algorithm for Nearest Neighbor Queries --- p.78 / Chapter 6.3 --- Summary --- p.83 / Chapter Chapter 7 --- Conclusion and Future Work / Chapter 7.1 --- Conclusion --- p.84 / Chapter 7.2 --- Future Work --- p.85 / Appendix Space Driven Algorithm / Chapter A.1 --- Introduction --- p.87 / Chapter A.2 --- Fixed Grid --- p.88 / Chapter A.3 --- Z-curve --- p.89 / Chapter A.4 --- Hilbert curve --- p.90 / Chapter A.5 --- Conclusion --- p.91 / Bibliography --- p.92
82

A Spatial Analysis of Ceramics in Northwestern Alaska: Studying Pre-Contact Gendered Use of Space

Braymer-Hayes, Katelyn Elizabeth 14 March 2018 (has links)
Activities and production among ethnographic Arctic peoples were primarily divided by gender. This gendered division of labor also extended to a spatial segregated pattern of the household in some Arctic cultures. Other cultures had a more gender-integrated spatial pattern of the household. There have been very few archaeological studies of gender in the Arctic, and even fewer studies of gendered use of space. In this thesis, I evaluated the existence of this gendered use of space in pre-contact Northwest Alaska. I also evaluated the existence of discrete activity spaces. I drew from both ethnoarchaeology and gender/feminist archaeology to both construct my hypotheses and interpret my results. I used ceramics, which were likely primarily made by and used by women, as a proxy for women's movement within the house. Ceramics are abundant and well-preserved in many Northwestern Alaskan sites, and are well suited for a robust spatial analysis. In addition to ceramics, I also evaluated the spatial density of other female artifacts, like ulus or scrapers, and male artifacts, like harpoon points or adzes, in order to further test the existence of gender specific use of space. I tested this using the HDBSCAN (Hierarchical Density Based Spatial Clustering of Applications with Noise) algorithm in Python, a programming language. HDBSCAN identifies discrete clusters of artifacts, as well as the persistence, or stability, of the cluster. Birnirk and Thule era (1300-150 BP) house features from Cape Espenberg, Alaska, were used to test these expectations. Based on the results of my spatial analysis, I did not find any evidence of gender specific use of space, nor did I find specific activity areas within the house. My findings are not necessarily an indication that gender-segregated use of space does not exist among pre-contact Northwest Alaskan people: I just did not find evidence supporting it. This could be, in part, due to issues of sample size, house size, and the role of secondary and post deposition processes in shaping the ceramic assemblage and distribution. While ceramics did cluster, they mostly clustered in the entrance tunnel of the house. This is likely the result of cleaning, storage, or other depositional processes. When ceramics did cluster in the main rooms, clustering was idiosyncratic. Male and female artifacts were not spatially segregated. Female artifacts were slightly more likely to cluster than male artifacts. Both sets of artifacts were generally in the same area as the ceramic clusters. While this study did not find evidence of gendered use of space, it still is an important contribution of addressing questions of gender in the Arctic. In addition, it is a valuable methodological contribution, using a clustering algorithm that previously has not been frequently used by archaeologists.
83

GIS Spatial Analysis of Arctic Settlement Patterns: A Case Study in Northwest Alaska

Junge, Justin Andrew 05 September 2017 (has links)
In northwest Alaska, archaeologists hypothesize that environmental variability was a major factor in both growing coastal population density, with large aggregated villages and large houses, between 1000 and 500 years ago (ya), and subsequent decreasing population density between 500 ya and the contact era. After 500 ya people are thought to have dispersed to smaller settlements with smaller house sizes in coastal areas, and perhaps, upriver. This settlement pattern was identified through research at four site locations over 30 years ago. The changing geographic distribution of sites, associated settlement size, and house size has not been examined in detail. A more careful examination of changing northwest Alaskan settlement patterns is needed before larger questions about socio-economic organization can be addressed. I use Geographic Information Systems (GIS) to evaluate the evidence for a geographic redistribution of Arctic peoples during the Late Holocene. The author constructed a database of settlement location and site attribute information, specifically the number of houses within each settlement and the size (m2). Data were collected from a dataset of Western Arctic National Parklands (WEAR), the Alaska Heritage Resource Survey (AHRS) database of archaeological sites in Alaska, 409 unpublished site reports and field notes curated by the National Park Service (NPS) and Bureau of Indian Affairs (BIA), and the results of recent fieldwork in northwest Alaska. A total of 486 settlements were identified within the northwest Alaska with 128 settlements having temporal and site attribute data. The author incorporated settlement size data into a GIS database and then carried out global, Moran's I, local Moran's I, and local Getis-Ord spatial analyses to test whether settlement redistribution occurred and if key settlement locations shifted after 500 ya. The site attribute data (number of houses and average size of houses) are used to test the additional aspects of the proposed settlement pattern change after 500 ya. A total of 83 settlements with 465 houses are used to test if the average size of settlements and average house size changed after 500 ya. The results of the spatial analyses indicate no statistically significant patterns in the spatial distribution of settlements. Site attribute analysis shows no statistical difference in the average number of houses per village or the average size of houses before or after 500 ya. The results of this work build our understanding of regional settlement patterns during the late Holocene. By testing settlement pattern change, i.e. settlement distribution, settlement size, and house size, future research into settlement pattern change can begin to evaluate likely causes for the observed changes. My method, specifically the use of GIS as a method for testing settlement pattern change, can be applied to other regions and temporal scales.
84

Image analysis of fungal biostructure by fractal and wavelet techniques

Jones, Cameron Lawrence, cajones@swin.edu.au January 1997 (has links)
Filamentous fungal colonies show a remarkable diversity of different mycelial branching patterns. To date, the characterization of this biostructural complexity has been based on subjective descriptions. Here, computerized image analysis in conjunction with video microscopy has been used to quantify several aspects of fungal growth and differentiation. This was accomplished by applying the new branch of mathematics called Fractal Geometry to this biological system, to provide an objective description of morphological and biochemical complexity. The fractal dimension is useful for describing irregularity and shape complexity in systems that appear to display scaling correlations (between structural units) over several orders of length or size. The branching dynamics of Pycnoporus cinnabarinus have been evaluated using fractals in order to determine whether there was a correlation between branching complexity and the amount of extracellular phenol-oxidase that accumulated during growth. A non-linear branching response was observed when colonies were grown in the presence of the aminoanthraquinone dye, Remazol Brilliant Blue R. Branching complexity could be used to predict the generalized yield of phenol-oxidase that accumulated in submerged culture, or identify paramorphogens that could be used to improve yield. A method to optimize growth of discrete fungal colonies for microscopy and image analysis on microporous membranes revealed secretion sites of the phenoloxidase, laccase as well as the intracellular enzyme, acid phosphatase. This method was further improved using microwave-accelerated heating to detect tip and sheath bound enzyme. The spatial deposition of secreted laccase and acid phosphatase displayed antipersistent scaling in deposition and/or secretion pattern. To overcome inherent statistical limitations of existing methods, a new signal processing tool, called wavelets were applied to analyze both one and two-dimensional data to measure fractal scaling. Two-dimensional wavelet packet analysis (2-d WPA) measured the (i) mass fractal dimension of binary images, or the (ii) self-affine dimension of grey-scale images. Both 1- and 2-d WPA showed comparative accuracy with existing methods yet offered improvements in computational efficiency that were inherent with this multiresolution technique. The fractal dimension was shown to be a sensitive indicator of shape complexity. The discovery of power law scaling was a hallmark of fractal geometry and in many cases returned values that were indicative of a self-organized critical state. This meant that the dynamics of fungal colony branching equilibrium. Hence there was potential for biostructural changes of all sizes, which would allow the system to efficiently adapt to environmental change at both the macro and micro levels.
85

Pneumonia and influenza hospitalizations in Ontario a spatial, temporal and spatial-temporal analysis /

Crighton, Eric J. Elliott, Susan J. January 1900 (has links)
Thesis (Ph.D.)--McMaster University, 2006. / Supervisor: Susan J. Elliott. Includes bibliographical references (leaves 166-171).
86

Bayesian hierarchical models for hunting success rates /

Woodard, Roger January 1999 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1999. / Typescript. Vita. Includes bibliographical references (leaves 75-77). Also available on the Internet.
87

Bayesian hierarchical models for hunting success rates

Woodard, Roger January 1999 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1999. / Typescript. Vita. Includes bibliographical references (leaves 75-77). Also available on the Internet.
88

The integration of spatial analysis techniques and decision support systems for natural resource management

Strager, Michael P. January 2004 (has links)
Thesis (Ph. D.)--West Virginia University, 2004. / Title from document title page. Document formatted into pages; contains ix, 144 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references.
89

Nearest neighbor queries in spatial and spatio-temporal databases /

Zhang, Jun. January 2003 (has links)
Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2003. / Includes bibliographical references (leaves 125-131). Also available in electronic version. Access restricted to campus users.
90

Spatial modelling and analysis of wireless ad-hoc and sensor networks: an energy perspective

Baek, Seung Jun 28 August 2008 (has links)
Not available / text

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