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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.
41

Artificial neural networks to detect forest fire prone areas in the southeast fire district of Mississippi

Tiruveedhula, Mohan P 09 August 2008 (has links)
An analysis of the fire occurrences parameters is essential to save human lives, property, timber resources and conservation of biodiversity. Data conversion formats such as raster to ASCII facilitate the integration of various GIS software’s in the context of RS and GIS modeling. This research explores fire occurrences in relation to human interaction, fuel density interaction, euclidean distance from the perennial streams and slope using artificial neural networks. The human interaction (ignition source) and density of fuels is assessed by Newton’s Gravitational theory. Euclidean distance to perennial streams and slope that do posses a significant role were derived using GIS tools. All the four non linear predictor variables were modeled using the inductive nature of neural networks. The Self organizing feature map (SOM) utilized for fire size risk classification produced an overall classification accuracy of 62% and an overall kappa coefficient of 0.52 that is moderate (fair) for annual fires.
42

Analysis of Tree Rings and Fire Scars to Establish Fire History

McBride, Joe R. January 1983 (has links)
Traditional counting of tree rings between fire scars to establish a fire history is examined for a better understanding of factors influencing fire scar formation and wound healing. The problem of dating fires which burn prior to or after the period of cambial activity is emphasized. A methodology for fire history studies based on fire scar and tree-ring analysis developed by Arno and Sneck (1977) is reviewed and elaborated upon. The importance of crossdating, height of sample cross sections, and problems associated with the extrapolation of data are discussed. Ongoing research involving the examination of the mineral concentration of tree rings and the presence of traumatic resin canals as markers of past fires is reviewed.
43

Effect of fire and wind-throw on a forest area

Coveney, Sister Mary Camilla January 1965 (has links)
Thesis (Ph.D.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / This study is a quantitative analysis of the effect of fire and wind-throw on a spruce-fir-northern hardwoods forest on Peaks Island, Casco Bay, Maine. Six years after the burn, data for the effect of fire on approximately 170 acres of this forest type, were collected and categorized. The qualitative characteristics of the herb and shrub layers were noted and the soil analyzed. A random sample of the tree density was obtained by using 10 x 10 meter quadrats. In this sampling three size classes were recognized, seedling, sapling, and 1.0-4.0 inch d.b.h. For each size class the following distributions were determined: percentage frequency, percentage density, percentage basal area, density per acre, basal area per acre; and cumulative figures for the relative density, relative basal area, and relative frequency of each species over 1 inch d.b.h. A similar study was carried out on 8.8 acres of a wind-throw area, and on 144 acres of spruce-fir-northern hardwoods forest. In the latter, additional size classes up to 24.0 inches d.b.h. were added. Determining frequencies in randomly distributed quadrats resolved in a positive direction the question of whether fire and wind-throw significantly affect the plant successional trend. Since the tree species in each of the three areas were found to be nearly identical, the Chi-square criterion was employed to decide whether the density distribution was independent of the area. Two significant factors resulted: (1) Of the twenty-one species in the spruce-fir-northern hardwoods forest, thirteen were represented among the eighteen species of the wind-throw area. The distribution of these thirteen species differed significantly in the two areas. (2) Thirteen of the species of the spruce- fir- northern hardwoods forest, were represented in the burn which contained altogether fifteen species. Again, the density distribution differed significantly for the two areas. The hypothesis that the frequency distribution was independent of the area was rejected in both tests since the value of the Chi-square calculated, for the densities in each size class, was significantly different from what could be expected by chance. This substantiated the conclusion that the three unique ecological environments accounted for the quantitative distribution of their species. [TRUNCATED] / 2031-01-01
44

Smokescreen : black/white/male/female bravery and southeast Australian bushfires

Finlay, Christine, School of Sociology & Anthropology, UNSW January 2005 (has links)
Black/white/male/female struggles over knowledge correctness and who is brave are examined inductively in the field of bushfires. The paradoxes of a white male icon are linked to contradictions in gender theories in disaster. In mainstream literature, assumptions of innate white male superiority in bravery justify white women???s diminution and white male domination. In feminist theory, women???s diminution is the problem and their bravery for struggling against hegemony applauded. Philosophies of bravery are explored in 104 semistructured interviews and 12 months??? fieldwork as a volunteer bushfirefighter. There is great variety in the ways volunteers cope with bushfires. However, evidence of white male hegemony emerges when volunteers complain of state and territory indifference to preventing property and environmental damage and injury and death. Evidence is examined that Indigenous Australians once managed bushfires better than a sprawl of bureaucracy. Bushfire service claims that Aborigines knew nothing about hazard reductions are contradicted. This debate over bushfire management leads to the discovery of a third epistemology breaking with claims of white male iconic bravery and bureaucratic mastery. To generalise about the habitus of claims to knowledge and bravery, I analyse Newcastle Herald articles from 1881-1981. Three competing knowledge fields and their associated struggles are examined; Indigenous Australians and white womens??? emancipatory struggles confront data on bushfirefighting. Bushfires emerge as a serious problem, a bureaucratic power base and a white male icon from the 1920s.
45

Cycling and speciation of mercury in soils at Cadillac Brook and Hadlock Brook watersheds, Acadia National Park, Maine /

Ruck, Philip Lawrence, January 2002 (has links)
Thesis (M.S.) in Civil Engineering--University of Maine, 2002. / Includes vita. Includes bibliographical references (leaves 95-100).
46

Development, fire history and current and past growth, of old-growth and young-growth forest stands in the Cascade, Siskiyou and mid-coast mountains of southwestern Oregon /

Sensenig, Thomas S. January 2002 (has links)
Thesis (Ph. D.)--Oregon State University, 2003. / Includes maps in pocket. Typescript (photocopy). Includes bibliographical references (leaves 146-166). Also available online.
47

Fire and its effects on mercury and methylmercury dynamics for two watersheds in Acadia National Park, Maine /

Johnson, Kenneth B., January 2002 (has links)
Thesis (M.S.) in Ecology and Environmental Sciences--University of Maine, 2002. / Includes vita. Bibliography: leaves 55-61.
48

Recovery of burned-reseeded and chemically treated oak-chapparral in Arizona

Tiedemann, Arthur R. January 1965 (has links)
No description available.
49

Smokescreen : black/white/male/female bravery and southeast Australian bushfires

Finlay, Christine, School of Sociology & Anthropology, UNSW January 2005 (has links)
Black/white/male/female struggles over knowledge correctness and who is brave are examined inductively in the field of bushfires. The paradoxes of a white male icon are linked to contradictions in gender theories in disaster. In mainstream literature, assumptions of innate white male superiority in bravery justify white women???s diminution and white male domination. In feminist theory, women???s diminution is the problem and their bravery for struggling against hegemony applauded. Philosophies of bravery are explored in 104 semistructured interviews and 12 months??? fieldwork as a volunteer bushfirefighter. There is great variety in the ways volunteers cope with bushfires. However, evidence of white male hegemony emerges when volunteers complain of state and territory indifference to preventing property and environmental damage and injury and death. Evidence is examined that Indigenous Australians once managed bushfires better than a sprawl of bureaucracy. Bushfire service claims that Aborigines knew nothing about hazard reductions are contradicted. This debate over bushfire management leads to the discovery of a third epistemology breaking with claims of white male iconic bravery and bureaucratic mastery. To generalise about the habitus of claims to knowledge and bravery, I analyse Newcastle Herald articles from 1881-1981. Three competing knowledge fields and their associated struggles are examined; Indigenous Australians and white womens??? emancipatory struggles confront data on bushfirefighting. Bushfires emerge as a serious problem, a bureaucratic power base and a white male icon from the 1920s.
50

An in-service training program for the state forestry department /

Thomas, Harold Alexander. January 1940 (has links)
Thesis (M.F.)--Oregon State College, 1940. / Typescript. Includes bibliographical references (leaves 98-99). Also available on the World Wide Web.

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