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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

New Developments in Forest Fire Control: Applicable to Grass and Brush Fires

Wagle, Robert F. 03 1900 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
42

Mapping fire affected areas in northern Western Australia - towards an automatic approach /

Candy, Katherine. January 2004 (has links)
Thesis (M.Phil.)--Murdoch University, 2004. / Thesis submitted to the Division of Science & Engineering. Accompanying CD-ROM contains Appendices 1-12 (leaves 198-298). Bibliography: leaves 184-195.
43

The ecology of fire in Hong Kong /

Chau, Kam-chiu, Lawrence. January 1994 (has links)
Thesis (Ph. D.)--University of Hong Kong, 1995. / Includes bibliographical references (leaf 242-254).
44

Forest fire incidence, damage and control measures in Ghana

Owusu-Afriyie, Kennedy. January 2008 (has links)
Thesis (Ph.D.)--Aberdeen University, 2008. / Title from web page (viewed on July 20, 2009). Includes bibliographical references.
45

Methods for evaluating the effects of forest fire management in Alberta

Murphy, Peter John January 1985 (has links)
Programs for the prevention and control of forest fires have evolved in response to a need to protect lives and property in forested settings, and to protect the perceived values of the forest itself. However, costs of these fire management activities have always been a concern to those who provide the funds, and considerable effort has been directed towards attempts to determine optimal levels of management effort. The question of costs has become more acute in recent years as forest services have developed increasingly sophisticated yet expensive methods for controlling fires. Compounding the problem has been an increase in frequency of fires. Determination of appropriate levels of fire control has been hampered by a lack of knowledge about the relationship between expenditure on fire control activities and the resulting area burned and losses incurred, and by an inability to describe the effect on this relationship of variations in fire season severity. This dissertation addresses these questions using the conditions in Alberta as a case study. Five hypotheses were tested and substantiated. 1. Descriptive historical accounts of fire policy and fire seasons can be verified by analysis of actual annual expenditures on fire. Annual reports were reviewed to describe the evolution of fire management policies. 2. There has been a decrease in area burned which is related to increased fire management effort. Analyses of age-class distribution obtained from the provincial forest inventory were used as a basis for reconstructing an estimate of historical rates of burn for the past 80 years. Cost data were obtained to try to quantify the relationship between level of expenditure and rate of burn. 3. Variations in fire season severity can be described better than by existing methods by considering both the potential for fire spread and the actual number of fires. A new index of fire load which combined fire rate of spread with number of fires was developed which achieved this result. 4. Potential area burned in the absence of fire control may be estimated by means of a fire growth model. A fire growth model was developed to provide a mathematical basis on which to estimate area burned in the absence of any fire management activity. 5. There is a relationship among fire season severity, fire management effort, and area saved from burning. The combined relationships among fire season severity, fire management effort, and area burned or value were applied to illustrate some of the analyses which may be conducted with these data through evaluation of the Alberta situation. / Forestry, Faculty of / Graduate
46

Carbon Monoxide Generation and Transport from Compartment Fires

Wieczorek, Christopher John 17 June 2003 (has links)
The aim of the present research was to gain a better understanding of the species generation and transport from enclosure fires. The species generation experiments were conducted with a half-scale ISO 9705 enclosure with three different ventilation conditions and heat release rates ranging from 50 kW to 500 kW. The transport study was conducted with a 6.1 m long hallway connected to the compartment in a head-on configuration. All measurements were performed at the compartment or hallway exit plane during the steady-state period of the fire. Measurements included species mole fractions of oxygen, carbon dioxide, carbon monoxide, and unburned hydrocarbons, along with gas pressure (used to determine gas velocities) and gas temperatures. Species mappings performed at the exit plane of the compartment indicated that the exiting species are not spatially uniform. Horizontal and vertical gradients in the species mole fractions were observed for all ventilation conditions and heat release rates examined. Predictive techniques developed previously were applied to the data obtained in the present study and were determined to be inappropriate for situations were the plume equivalence ratio was not equal to the global equivalence ratio. A new methodology for predicting species levels at the exit plane of an enclosure was developed. The proposed methodology correlates the species yields based on the combustion within the compartment as a function of a non-dimensional heat release rate. The non-dimensional heat release rate is based on the fuel load and geometrical parameters of the enclosure. The present methodology in applicable to situations where a well-mixed uniform layer is not present and the overall global conditions are of interest. Species transport to remote locations was also examined. Experiments were conducted with the baseline ventilation at x = 0 m (the compartment/hallway interface) and three different ventilation conditions at x = 6.1 m (end of hallway). The three ventilation conditions consisted of the narrow, baseline, and wide doorways. Experiments were conducted for heat release rates of 85 kW, 127 kW, and 150 kW. The results from the tests indicated that, for over-ventilated compartment fires, the hallway and hallway ventilation had no impact on the species generation within the compartment. This allows the correlations developed from the compartment study to be applied to more complex scenarios. Differences in species mole fractions between x = 0 m and x = 6.1 m were shown to be a result of air entrainment into the upper layer within the hallway, which acted as a dilutent or as a source of oxygen for further oxidation reactions. For non-dimensional heat release rates less than 1.0, the reduction in carbon monoxide levels along the hallway was a result of dilution, while for non-dimensional heat release rates greater than or equal to 1.0 the reduction in carbon monoxide levels along the hallway was a combination of dilution and further oxidation reactions. / Ph. D.
47

A systems evaluation of life safety in fires

Hinks, John January 1987 (has links)
No description available.
48

Environmental controls of red pine (Pinus resinosa Ait.) : distribution and abundance

Flannigan, Michael D. January 1993 (has links)
No description available.
49

Production of smoke and carbon monoxide in underventilated enclosure fires

Ukleja, Sebastian 25 May 2012 (has links)
This work is an experimental and theoretical analysis of factors and conditions affecting smoke and carbon monoxide (CO) production in corridor-like enclosure fires. Thirty eight experiments were performed in a three metre long corridor-like enclosure having a cross section 0.5 m x 0.5 m, door-like openings in the front panel and a propane gas burner located near the closed end. Measurements of smoke and carbon monoxide concentrations were performed at locations inside the enclosure and also in the exhaust duct of a hood collecting the combustion products. The main conclusion of this work is that smoke production depends not only on the fuel and Global Equivalence Ratio (GER) - as is reported in the literature - but also on the temperatures and residence time inside the enclosure, at least for the experimental conditions examined in this study. Additionally, it was found that the smoke concentration inside the enclosure was increasing during the ventilation controlled regime even after external burning started. Such increase was verified by temperature, smoke and velocity measurements inside the enclosure. The increase was due to reverse flow behind the flames travelling along the corridor. Namely, the gases reversed direction behind the flames with hot gases travelling in the upper layer backwards towards the closed end of the corridor in contrast to hot gas movements towards the opening in front of the flames. This recirculation was confirmed by velocity and oxygen concentration measurements in the upper and lower layers inside the enclosure. In addition, the present results show that the relationship reported in the literature between smoke and carbon monoxide production during overventilated conditions yco/ys ≈ constant, is no longer valid during an underventilated enclosure fire. The ratio yco/ys increases for the Global Equivalence Ratios of the enclosure greater than one. The obtained results are useful for CFD validation and specifically applicable for assessing smoke hazards in corridor fires in buildings where smoke concentrations can be much larger than anticipated owing to leakage to adjacent rooms behind travelling flames.
50

Temporal and spatial variability of fire occurrence in Western Oregon, A.D. 1200 to present /

Berkley, Evelyn L. January 2000 (has links)
Thesis (M.S.)--University of Oregon, 2000. / Computer optical disc in pocket of back cover titled: Animated time series of fire occurrence in Western Oregon, A.D. 1200-2000. Typescript. Includes vita and abstract. Includes bibliographical references (leaves 107-110). Also available for download via the World Wide Web; free to UO users.

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