In this study, I addressed how a large-scale wildfire affected a prairie arthropod community in southern Alberta, Canada. First, I looked at the general effects of disturbance on the arthropod community. Second, I addressed how processes such as competition and secondary succession may have affected diversity in this arthropod community. Third, I determined how the arthropod community trophic structure was regulated. Results showed that the effect of disturbance on arthropods varies greatly by taxa. Factors, such as site, year, distance from disturbance edge, as well as the disturbance itself, were important in determing the abudance, biomass, richness, and diversity of the arthropod community. There were strong year-to-year differences hat exceeded the disturbance effects. Results showed that the processess behind the intermediate disturbance hypothesis, succession and competition are not detectable in this arthropod community. This arthropod community was likely regulated in a bottom-up manner, in which herbivores ultimately control the abundance of predators and parasitoids. / x, 97 leaves : ill. ; 28 cm.

The objective of this study is to formulate a general 3D material-structural analysis framework for the thermomechanical behavior of steel-concrete structures in a fire environment. The proposed analysis framework consists of three modeling parts: fire dynamics simulation, heat transfer analysis, and a thermomechanical stress analysis of the structure. The first modeling part consists of applying the NIST (National Institute of Standards and Technology) fire dynamics simulator (FDS) where coupled Computational Fluid Dynamics (CFD) with thermodynamics are combined to model the fire progression within the steel-concrete structure. The goal is to generate the spatial-temporal (ST) solution variables (temperature, heat flux) on the surfaces of the structure. The FDS-ST solutions are generated in a discrete numerical form. Continuous FDS-ST approximations are then developed to represent the temperature or heat-flux at any given time or point within the structure. An extensive numerical study is carried out to examine the best ST approximation functions that strike a balance between accuracy and simplicity. The second modeling part consists of a finite-element (FE) transient heat analysis of the structure using the continuous FDS-ST surface variables as prescribed thermal boundary conditions. The third modeling part is a thermomechanical FE structural analysis using both nonlinear material and geometry. The temperature history from the second modeling part is used at all nodal points. The ABAQUS FE code is used with newly developed external user subroutines for the second and third simulation parts. The main objective is to describe the nonlinear temperature-dependency of the specific heat of concrete materials, especially high-strength concretes, that drastically affects their transient thermal solution. New algorithms are also developed to apply the continuous FDS-ST surface nodal boundary conditions in the transient heat FE analysis. The proposed modeling framework is applied to predict the temperature and deflection of the well-documented Cardington fire tests and to predict the time-to-collapse of the recent Oakland bridge fire caused by a fuel-truck accident.

Thesis (M.S.)--Oregon State University, 2007. / Printout. Includes bibliographical references (leaves 33-43). Also available on the World Wide Web.

Diferentemente das linhas adotadas por um bom número de trabalhos em Estudos da Tradução que têm por objetivo uma análise crítica de tradução ou uma tradução comentada, nosso projeto busca tratar a tradução, mais especificamente a tradução literária, não como um objeto em si, mas como parte integrante do processo de construção de uma obra. Para tanto, nosso pressuposto é a noção aristotélica de ato e potência. A nosso ver, a gênese da tradução literária, como potência, coincide com o início da escritura da obra, como ato, ou seja, a tradução literária é inerente à obra em estado virtual, como um ser em devir, podendo ou não vir a se materializar como obra traduzida. Sob essa ótica, acreditamos que toda e qualquer análise de tradução literária envolva um mergulho não apenas no contexto de sua produção e em seu produto final, mas também nos elementos que envolvem a produção da obra de partida. Baseando-nos nas noções de Dominique Maingueneu (2001) a respeito do contexto da obra literária e no alicerce linguístico em enunciação oferecido por Émile Benveniste (1976), pudemos associá-los a outras importantes contribuições, como os conceitos de posição tradutória, projeto de tradução e horizonte do tradutor propostos por Antoine Berman (1995) que, se observados relacionalmente dentro de cada espaço de negociação que constitui todo processo tradutório em suas diversas etapas, pressupõem necessariamente uma esfera ética. Ao adotarmos a noção proposta por Maurício Mendonça Cardozo (2007), baseando-se em Henrique C. de Lima Vaz (2015), que traz o conceito da palavra ética originalmente como lugar, podemos entendê-la como sendo a consciência da posição que se ocupa em uma dada relação o lugar de onde se fala e para quem se fala , oferecendo, assim, campo fértil para pensarmos efetivamente a ética da tradução como práxis e projetá-la em termos bermanianos. Sob esse arcabouço teórico, a questão das posições enunciativas emerge de maneira fundamentada para uma análise do caso específico da tradução Fires (1981), por Dori Katz, a partir da obra Feux (1936), de Marguerite Yourcenar, em que diversas são as variáveis, que não a relação isolada entre tradutor e texto de partida. Em Feux-Fires, aquilo que chamaremos de uma espiral de posições enunciativas compõe um quadro bastante particular em tradução literária. / Unlike the line adopted by many works in Translations Studies whose purpose are translations critical analysis or commented translations, our project aims at approaching translation, and more specifically literary translation, not as an object in itself, but as an integral part of the building process of a literary work. Assuming Aristotles concept of potency and act, in our view, the genesis of literary translation, as potency, coincides with the beginning of the literary works writing, as an act, i.e. , the literary translation is inherent to the literary work in a virtual state, as a being to be, whether it is eventually materialized as a translated literary work or not. From this perspective, we believe that each and every analysis of literary translation involves not only jumping into its context of production and its final product, but also into the elements surrounding the production of the source work. Based on the notions of Dominique Maingueneau (2001) about the context of the literary work and on the linguistic grounds offered by Émile Benveniste (1976), we managed to associate them to other important contributions, such as the concepts of translational position, translation project, and horizon of translation proposed by Antoine Berman (1995), which necessarily assume an ethical domain if regarded in a relational perspective within every negotiation space that constitutes each translation project in its many phases. By adopting the notion proposed by Maurício Mendonça Cardozo (2007) based on Henrique C. de Lima Vaz (1999), who presents the concept of the word ethics originally as a place, it may be understood as the awareness of the position one holds in a given relation the place where one speaks from and to whom , thus offering fertile ground for ethics in translation to be effectively viewed as praxis and to be projected in bermanian terms. Under this theoretical framework, the question of enunciative positions emerges in a well-founded way for an analysis of the particular case of the translation Fires (1981), by Dori Katz, of the work Feux (1936), byMarguerite Yourcenar, in which many are the variables, other than the isolated relation between the translator and the source text. In Feux-Fires, what we call a spiral of enunciative positions compose a very specific scenario in literary translation.

Skogsbränder utgör ett stort problem både lokalt, regionalt och globalt. De förstör stora värden, frigör stora mängder kol ut i atmosfären och är mycket resurskrävande att bekämpa. Under markytan kan glödbränder fortsätta långt efter att flambranden ovan mark är släckt. Glödbränder brinner mycket långsammare än de öppna flambränderna, men är istället svårare att upptäcka och ställer andra krav vid bekämpning. En typ av glödbrand som kan påträffas i skogsbränder är torvbränder. Det är glödbränder som uppstår i torvmarker som utsatts för torka. Branden äter sig sakta igenom torven och kan gå djupt ner i marken. Svårigheter med att lokalisera bränderna och att få ner tillräckligt med vatten i de djupare torvlagerna gör dem svåra att släcka. Idag används ofta dimspikar, även kallade jordspett, för att släcka bränder som gått ner under markytan. På vissa ställen har även skärsläckaren börjat användas. Detta arbete syftar till att ge en bättre förståelse för de två verktygens funktion och effektivitet vid släckarbete av torvbränder. För att göra det har två tester genomförts på Luleå räddningstjänsts övningsfält, ett för dimspik och ett för skärsläckare. En försöksuppställning byggdes upp med en invändig tvärsnittsarea på 80×80 cm och en höjd på 1,1 m. Den fylldes sedan med torv som packades lätt tills torvlagret var 1 m tjockt. Det som undersöktes var verktygens penetreringstid för vattnet att nå 1 m ner i torven samt hur stor spridning vattnet fick över tvärsnittsarean på djupet 1 m. Båda verktygen hade liknande flöden (56 l/min för skärsläckaren och 58 l/min för dimspiken) så de uppmätta skillnaderna i resultat berodde på hur vattnet transporterades, inte på mängden vatten. Skärsläckaren slog igenom på cirka 1 sekund och bildade ett utgångshål på cirka 1 dm2, där det var blött ytterliga någon centimeter runtomkring för en total våt area på cirka 2 dm2. Testet avslutades efter 30 sekunder då ingen förändring kunde ses i storleken på utgångshålet och den våta arean från efter de första få sekunderna. Vattnet sprutade rakt igenom torven. Dimspiken vätte igenom efter 26 sekunder och den våta arean växte kontinuerligt. Inget utgångshål bildades i detta fall. När dimspiken stängdes av efter 1 minut och 45 sekunder, så hade cirka 32 dm2 blivit blött; vilket motsvarar ungefär halva tvärsnittarean hos försöksuppställningen. Spridning fortsatte efter att dimspiken slagits av och nästan hela tvärsnittsarean var blöt efter ytterligare några minuter. Skärsläckaren hade en mycket snabb penetreringstid, men sprutade istället mycket vatten rakt igenom torven, vilket medförde att stora mängder vatten passerade genom torven utan att väta en stor yta eller volym. Dimspiken hade en mycket längre penetreringstid, i gengäld så sköts inte vattnet rakt igenom torven utan spred ut sig och vätte en större yta. Båda verktygen har sina för- och nackdelar. Vilket verktyg som är bäst är väldigt situationsberoende. Skärsläckaren har bland annat snabbare penetreringstid och möjliggör fler snabba ingrepp, medan dimspiken täcker en större area per angreppspunkt och är lättare och säkrare att hantera. / Wildfires are a major problem both locally, regionally and globally. They destroy large values, emit large quantities of carbon into the atmosphere and are very resource intensive to fight. Smoldering fires can continue under the ground surface long after the flaming fire above ground is put out. Smoldering fires burn much slower than the flaming fires, but in turn they are harder to discover and require different means to fight. Peat fire is one type of smoldering fire that can be found in wildfires. It is a smoldering fire that occur in peatlands exposed to drought. The fire slowly eats its way through the peat and can go deep into the ground. Difficulty locating them and getting enough water into the deeper peat layers makes them difficult to extinguish. Today, fognails are often used to extinguish smoldering fires in the ground. The cutting extinguisher is another tool that has been used to fight smoldering fires in the ground in some cases. This bachelor thesis aims to provide a better understanding of the function and efficiency of the two tools in extinguishing peat fires. To do this, two tests have been carried out on the fire department’s training field in Luleå, one with a fognail and one with a cutting extinguisher. A test stand was constructed with an internal cross-sectional area of ​​80×80 cm and a height of 1.1 m. It was then filled with peat which was lightly packed until the peat layer was 1 m thick. What was investigated was the tools’ penetration time for the water to reach 1 m down into the peat and the size of the water spread over the cross-sectional area at the depth of 1 m. Both tools had similar flows (56 l/min for the cutter extinguisher and 58 l/min for the fognail) so the differences arose in how that water was used, not the amount of water. The cutting extinguisher broke through in about 1 second and formed an exit hole of about 1 dm2 with additional wetness of a few centimeters around for a total wet area of ​​about 2 dm2. The test was terminated after 30 seconds when no change could be seen in the size of the output hole or the wet area from after the first few seconds. The water sprayed right through the peat. The water from the fognail got through after 26 seconds and the wet area grew continuously. No exit hole was formed in this case. When the fognail was turned off after 1 minute and 45 seconds, about 32 dm2 had become wet, which corresponds to about half the cross-sectional area of the test stand. However, spreading continued despite the fognail being turned off and almost the entire cross-sectional area was wet after a few more minutes. The cutting extinguisher had a very fast penetration time, but as a result it sprayed a lot of water right through the peat without wetting a large area or volume. The fognail had a much longer penetration time, but in return, the water was not shot straight through the peat, but spread out and wet a larger surface. Both tools have their advantages and disadvantages. Which tool is the best depends a lot on the situation. The cutting extinguisher has, among other things, a faster penetration time and allows for more rapid interventions, while the fog nail covers a larger area per attack point and is easier and safer to handle.

No description available.

A research report submitted to the Faculty of Science, University of the Witwatersrand, and Johannesburg in partial fulfillment of the requirements for the degree Master o f Science (Geographical Information System and Remote Sensing) Johannesburg, 2017. / The purpose of this analysis was to map the frequency of veld fires using remote sensing data from 2012 to 2016. The analysis successfully answered three objectives which are mapping the spatio-temporal pattern of veld fires in Mazowe district from 2012 to 2016, assessing the strength of association between burnt area and land cover classes and to determine the degree of veld fires in Mazowe district. The analysis of the veld fire frequency was undertaken in ENVI 5.3 and Arc Map software. Landsat imagery and MODIS fire products were collected and processed. For each year two Landsat images were used, one image before the season of fire starts which was used to classify the land cover classes and one image after fire season which was used to classify the burnt and unburnt classes. The MODIS fire products data were used to validate the burnt and the unburnt classification. The evaluations of the classifiers were done through accuracy assessment using confusion matrix and the results ranged from 85 to 95%.The study quantified the relationship between burnt areas land cover classes. The study also calculated the fire frequency. The results revealed that the veld fire frequency was high in A1 farms which measures 5 hectares, A2 farms which measures average of 318 hectares and grasslands compared to other land tenure and land cover classes. Areas with high frequency were observed in south, south west and some central parts of Mazowe district. There was high fire occurrence in 2012 and 2014. The study also noted that the fire occurrence was gradually decreasing, however the levels of fire occurrence remains high. The study concluded that A1, A2 farms and grasslands are prone to veld fires. The study recommends adaption of remote sensing techniques in eradicating veld fires. / MT 2017

"The primary purpose of this research was to quantify fire suppression and fire intensification phenomena for water spray application to high flash point hydrocarbon oil pool fires. Test data and analyses of the phenomena include the drop size distribution and application and delivered densities of various water sprays, and spray-induced oil cooling and oil splattering for mineral seal oil and for cooking oil 30-cm diameter pool fires. Four different types of tests were conducted as described below. A Dantec Particle Dynamic, phase Doppler, Analyzer was used to measure the water drop sizes and velocities generated by 13 selected nozzles and sprinkler heads. Most measurements were made 0.91 m (3 ft) below the nozzles/sprinklers, since this was the location of the center of the hydrocarbon pool in later fire tests. The correlations for the volume-median drop diameter, dw, were of the form , where D is the nozzle orifice and is the spray Weber number based on D and the nozzle velocity. A ring burner was designed and constructed for uniformly heating oil pool surfaces from above and igniting them. The resulting oil temperatures while the oil was heated to its flash point satisfied the one-dimensional transient heat conduction model for a semi-infinitely thick solid with a shallow heated layer near the surface. Water sprays actuated when the oil surface temperature reached its flash point rapidly cooled the heated layer and caused mixing with the cooler oil below. Fire suppression tests were conducted to determine the relationship between required water spray density, drop size, and oil temperature in order to achieve suppression. A data correlation using non-dimensional parameters was developed to quantify the fire suppression criteria for the high flash point oil fires. Oil pool fires with the higher flash point oils, such as the 291oC flash point soybean oil, could be suppressed with much lower water densities than those of the lower flash point (137oC) mineral seal oil. However, if the water spray drop sizes are sufficiently small, the lower flash point oil fires can also be extinguished with lower spray densities. The NFPA 15 specified critical water density (0.30 gpm/ft2, 12 mm/min) to extinguish high flash point pool fires is only valid for mineral seal oil when the drop size is lower than about 300 µm. It is valid with larger drop sprays only when the flash point of the oil is higher than 190 according to the correlation developed here. Spray-induced pool fire intensification tests were conducted under a fire products calorimeter for measuring heat release rates. Supplemental oil vaporization rate tests were also conducted to determine the contributions of oil vaporization and oil splattering to the intensified fire. Results showed that vaporization could only account for between 1% and 1.7% of the heat release rate in intensified mineral seal oil fires, and less than 1% of the heat release rate in intensified soybean oil fires. The remainder is due to spray-induced oil splattering, which increased with increasing drop Weber number as well as increased oil temperature. The heat release rate is enhanced by factor from 2.12 to 5.55 compared to the heat release rate of free burning cooking oil. For mineral seal oil, this ratio is in the range 0.92 to 1.25 for the spray conditions tested. Correlations with the dimensionless factors of and the Weber number of the water spray were also developed to quantify the ratio of the splattered oil to applied spray density."

Many studies of the fire induced thermal and structural behaviour in large compartments, carried out over the past two decades, show a great deal of non-uniformity, unlike the homogeneous compartment temperature assumption in the current fire safety engineering practice. Furthermore, some large compartment fires may burn locally and they tend to move across entire floor plates over a period of time as the fuel is consumed. This kind of fire scenario is beginning to be idealized as 'travelling fires' in the context of performance‐based structural and fire safety engineering. However, the previous research of travelling fires still relies on highly simplified travelling fire models (i.e. Clifton's model and Rein's model); and no equivalent numerical tools can perform such simulations, which involves analysis of realistic fire, heat transfer and thermo-mechanical response in one single software package with an automatic coupled manner. Both of these hinder the advance of the research on performance‐based structural fire engineering. The author develops an extended travelling fire method (ETFM) framework and an integrated comprehensive tool with high computational expediency in this research, to address the above‐mentioned issues. The experiments conducted for characterizing travelling fires over the past two decades are reviewed, in conjunction with the current available travelling fire models. It is found that no performed travelling fire experiment records both the structural response and the mass loss rate of the fuel (to estimate the fire heat release rate) in a single test, which further implies closer collaboration between the structural and the fire engineers' teams are needed, especially for the travelling fire research topic. In addition, an overview of the development of OpenSees software framework for modelling structures in fire is presented, addressing its theoretical background, fundamental assumptions, and inherent limitations. After a decade of development, OpenSees has modules including fire, heat transfer, and thermo‐mechanical analysis. Meanwhile, it is one of the few structural fire modelling software which is open source and free to the entire community, allowing interested researchers to use and contribute with no expense. An OpenSees‐based integrated tool called SIFBuilder is developed by the author and co‐workers, which can perform fire modelling, heat transfer analysis, and thermo-mechanical analysis in one single software with an automatic coupled manner. This manner would facilitate structural engineers to apply fire loading on their design structures like other mechanical loading types (e.g. seismic loading, gravity loading, etc.), without transferring the fire and heat transfer modelling results to each structural element manually and further assemble them to the entire structure. This feature would largely free the structural engineers' efforts to focus on the structural response for performance-based design under different fire scenarios, without investigating the modelling details of fire and heat transfer analysis. Moreover, the efficiency due to this automatic coupled manner would become more superior, for modelling larger structures under more realistic fire scenarios (e.g. travelling fires). This advantage has been confirmed by the studies carried out in this research, including 29 travelling fire scenarios containing total number of 696 heat transfer analysis for the structural members, which were undertaken at very modest computational costs. In addition, a set of benchmark problems for verification and validation of OpenSees/SIFBuilder are investigated, which demonstrates good agreement against analytical solutions, ABAQUS, SAFIR, and the experimental data. These benchmark problems can also be used for interested researchers to verify their own numerical or analytical models for other purposes, and can be also used as an induction guide of OpenSees/SIFBuilder. Significantly, an extended travelling fire method (ETFM) framework is put forward in this research, which can predict the fire severity considering a travelling fire concept with an upper bound. This framework considers the energy and mass conservation, rather than simply forcing other independent models to 'travel' in the compartment (i.e. modified parametric fire curves in Clifton's model, 800°C‐1200°C temperature block and the Alpert's ceiling jet in Rein's model). It is developed based on combining Hasemi's localized fire model for the fire plume, and a simple smoke layer calculation by utilising the FIRM zone model for the areas of the compartment away from the fire. Different from mainly investigating the thermal impact due to various ratios of the fire size to the compartment size (e.g. 5%, 10%, 25%, 75%, etc.), as in Rein's model, this research investigates the travelling fire thermal impact through explicit representation of the various fire spread rates and fuel load densities, which are the key input parameters in the ETFM framework. To represent the far field thermal exposures, two zone models (i.e. ASET zone model & FIRM zone model) and the ETFM framework are implemented in SIFBuilder, in order to provide the community a 'vehicle' to try, test, and further improve this ETFM framework, and also the SIFBuilder itself. It is found that for 'slow' travelling fires (i.e. low fire spread rates), the near‐field fire plume brings more dominant thermal impact compared with the impact from far‐field smoke. In contrast, for 'fast' travelling fires (i.e. high fire spread rates), the far‐field smoke brings more dominant thermal impact. Furthermore, the through depth thermal gradients due to different travelling fire scenarios were explored, especially with regards to the 'thermal gradient reversal' due to the near‐field fire plume approaching and leaving the design structural member. This 'thermal gradient reversal' would fundamentally reverse the thermally‐induced bending moment from hogging to sagging. The modelling results suggest that the peak thermal gradient due to near‐field approaching is more sensitive to the fuel load density than fire spread rate, where larger peak values are captured with lower fuel load densities. Moreover, the reverse peak thermal gradient due to near‐field leaving is also sensitive to the fuel load density rather than the fire spread rate, but this reverse peak value is inversely proportional to the fuel load densities. Finally, the key assumptions of the ETFM framework are rationalised and its limitations are emphasized. Design instructions with relevant information which can be readily used by the structural fire engineers for the ETFM framework are also included. Hence more optimised and robust structural design under such fire threat can be generated and guaranteed, where we believe these efforts will advance the performance‐based structural and fire safety engineering.

Fire is a major disturbance force that affects global ecosystems and associated biomes and plays a pivotal role in the determination of ecosystem structure, functionality and dynamics. Anthropogenic environmental disturbances have resulted in shifts in fire regimes and the biogeochemical processes of these ecosystems are thus unable to function as they have done in the past, impacting both floral and faunal species. Therefore there is a need for anthropogenic management. Prescribed burning is one of the few beneficial fire management options available to decrease the severity of wildfires, decrease the associated costs in suppressing these fires and restore fire-dominated ecosystems. The uKhahlamba Drakensberg Park World Heritage Site (UDP-WHS) is predominantly managed for water resource and nature conservation, and fire hazard reduction. It is divided into management compartments in which prescribed management burns are conducted, (i.e. manager’s burn by compartment). These compartments are subdivided by three altitudinal belts (alpine, sub-alpine and montane). Each of these belts contains different vegetation communities and therefore requires different fire regimes. However these compartments do not coincide with the natural contours and consequently, the altitudinal belts of the Park. This is problematic for management as a certain percentage per altitudinal belt is required to be burnt annually. When burning a compartment that falls within two or more belts, the total area of that compartment needs to be sub-divided into its respective altitudinal belts as a whole compartment can be prescribed to burn not a sub-division thereof. A fire management environmental decision support system (EDSS) was developed to achieve prescribed burning objectives in the UDP-WHS. The system is based on ecologically ideal fire regimes and fire management objectives of the heritage site, using GIS and associated graphs to visually display the required fire regimes. The EDSS data preparation, statistical analysis and modelling was completed using ESRI ArcGIS suite (ArcMap, Scene and Catalog). Its main components are two models, an excel spreadsheet and an ArcMap document. The spreadsheet contains the historical burning data of the management compartments based on the compartment codes, with each compartment being not burnt or having a burning treatment. Years Since Last Burnt (YSLB) was calculated from these data and joined to the management compartments in the ArcMap document. The Intermediate output model was developed to create numerous temporary outputs allowing decision makers to decide which compartments to treat with prescribed burning by re-running the model with required alterations. The second model (Final Output model) is then run to export the selected burning treatment in table format to update the original historical data, and consequently YSLB, in the excel and ArcMap document. The ArcMap document contains the user interface housing the graphs for each altitudinal belt showing the percentage area selected to be burnt per YSLB compared to the minimal, maximum and ideal fire regimes. The fire management EDSS for the UDP-WHS consists of an ArcMap document, geodatabase, excel document and folders, which are all housed in one single folder. The use of GIS and EDSSs in environmental management improves the efficiency and accuracy of the decision making process and provides the ability to validate outputs. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.