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1.
This article describes a new model that simulates the spread of post-earthquake urban fires. Adapting and integrating compartment fire models, this new model explicitly represents: (1) the evolution of fire within a room or roof; (2) room-to-room spread within a building through doorways, by burning through walls and ceilings, and by leapfrogging between windows; and (3) building-to-building spread by window flame impingement; radiation from window flames, room gas, and roof flames; and branding. The model can be used to explore how much, how fast, where, and by what modes fires will spread, and what factors influence fire spread.  相似文献   

2.
The accounts of explorers and colonists in the Kimberley region of Western Australia were searched to find records of landscape burning by Aborigines. Analyses of these records provide estimates of the spatial and temporal patterns of fire across the region in historic times. The seasonality of fire varied across the region. In northern parts of the Kimberley landscape fire was recorded from May to October with peak levels in June and September. In southern parts of the region there are records of burning as early as February and March, through to August but no records of fire were made in late dry season months. Modern fire regimes were compared with historic by superimposing the routes taken by five explorers over a modern fire history map derived from satellite imagery. Tallies of the number of modern fires that intersect the explorer's daily and monthly route were compared with actual observations of fire made by the explorers in historic times. The results indicate an increase in early dry season fires and the overall frequency of fires across the region in modern times. Explorers' accounts were also examined to derive further information regarding Aboriginal landscape burning in different environments and to distinguish landscape burning from other uses of fire such as smoke signals and cooking fires.  相似文献   

3.
This paper seeks to assist in defining a role for a suite of adapted techniques of analysis and interpretation that are drawn primarily from the methods of contemporary forensic fire investigation. In so doing, the paper identifies a general paucity of literature providing detailed discussions of structural fires preserved in the archaeological record. In addition the paper provides a generalised account of the manner in which structural fires (most especially compartment fires, defined later) will tend to burn and which tools can assist in the interpretation of fire dynamics, the identification of points of origin of fire within buildings, and the response of building materials to burning. Ultimately, such an approach can improve understanding of past structures, and also provide an interpretative avenue for understanding human response to fire and the risk of structural fire in the past.  相似文献   

4.
清代的消防组织由属于官府的巡城官兵与属于民间的“水会”两大系统组成,行政、军事与消防的一体化管理是清代消防组织的特点。以现代人的眼光来看,清代的消防组织在管理与培训等方面已经具有现代科学化的某些内容。而纵观由太平桶到火烛车再到水龙所形成的救火工具发展的三部曲,我们也不难看到人们在与火灾进行斗争中的进步。  相似文献   

5.
书画文物由于材质脆弱,容易受修复材料的影响。为探讨豆浆水在书画文物修复中的应用性能, 采用宣纸为纸样通过模拟加速试验测试了豆浆水处理后纸张的物理性能、聚合度、表面形态和化学结构 的变化。结果表明,豆浆水处理后,纸张纤维表面和蛋白质形成更多的氢键,可以提高纸张的抗水性能, 对纸张聚合度影响低于胶矾水,扫描电镜结果表明豆浆水处理后纤维表面形成一层胶状物质。本研究 为豆浆水的应用提供了依据。  相似文献   

6.
The influence of altered fire regimes on the denudation of a catchment is determined from alluvial deposits of the last 10,000 yrs and by monitoring runoff and erosion before and after a wildfire. An increase in fire frequency beginning at 3,000–4,000 yrs BP, as a result of intensified Aboriginal burning, did not change the mechanisms or rates of denudation nor did it cause widespread alluviation as suggested by others. The results of monitoring show that before and after mild fires there is insufficient runoff on most slopes to entrain sediment. Only after intense fires are runoff and erodibility increased enough to significantly accelerate erosion. Conditions are then identified which are most likely to lead to accelerated erosion from altered fire regimes in other catchments.  相似文献   

7.
This paper investigates the relationships between areas of building fire incidence, levels of socio-economic disadvantage and the underlying socio-economic characteristics in the South East Queensland (SEQ) region, Australia. Disaggregated fire incident data was acquired from the Queensland Fire and Rescue Service (QFRS) and then aggregated to the Statistical Local Area (SLA) level. The Australian Bureau of Statistics (ABS) defined index of socio-economic disadvantage (called ‘SEIFA’) has been used as the basis to identify relationships between socio-economic disadvantage and building fires. A regression model was then developed to predict the incidence of building fires using a range of socio-economic variables. Five significant predictors were identified that include: i) percentage of unemployed, ii) proportion of Indigenous population, iii) families living in separate dwellings, iv) one parent, and v) parent families with children less than fifteen years of age. Results also show that the distribution of building fires varies markedly across the SEQ region, with some of the Brisbane inner suburbs, areas of high socio-economic disadvantage, and parts of inland SEQ associated with relatively high fire rates.  相似文献   

8.
The Mediterranean ecosystem of Mt. Carmel, Israel, is subjected to an increasing number of forest fires of various extents and severities. The impacts of forest fires on runoff and erosion are widely documented and include increased peak flows and soil loss until the return of a vegetation cover. Most studies, however, treat fire as a single event, whereas the present study is aimed at exploring the long‐term effects of repeated forest fires on eco‐geomorphic processes. The study integrates the results of plot‐based, detailed analysis of post‐fire runoff and erosion with vegetation recovery analysis, at a temporal‐spatial scale which includes the effect of reburning. Our results indicate that forest fires lead to a significant increase in runoff and sediment yields, particularly during the first two years following the disturbance, up to five orders of magnitude higher than from the adjacent unburnt control plots.  相似文献   

9.
10.
During the extended El Nin?o drought of 1997–8, fires devastated Indonesia’s forests, creating a vast shroud of smoke that reached as far as mainland Southeast Asia. This article examines the interpretation of these fires — their causes, damages and solutions — by the Indonesian government, international donors, environmental activists and local farmers. It explores the contexts and consequences of these discourses of disaster, and specifically investigates the central role of remote technology — a ‘hegemonic’ representational tool, in some circumstances creatively appropriated to serve new democratic agendas. A narrow focus on remotely sensed data is not strictly a methodological but also a political choice, one which obscures alternative experiences of disaster and produces solutions that do not address long term social and political processes leading to the fires. What is missing from most current analyses of the fires, and from remote assessments in general, is a textured understanding of social landscapes and the role they play in creating fire hazards.  相似文献   

11.
We show that carbonized fruits and seeds recovered from Middle Stone Age deposits in rock shelters are likely to have been carbonized as part of post-depositional processes. We buried indigenous South African fruits, nuts and seeds at pre-determined depths and distances from the centers of experimental fires. The cold ashes of the hearths and the sand surrounding them were subsequently excavated, using standard archaeological techniques and dry-screening. The fruiting structures from the oxidizing part of the fire were burnt to ashes, whereas those buried in sand under anoxic conditions survived in varying forms. Those buried 5 cm below the center of the fire were carbonized; those buried 10 cm below the center of the fire were dehydrated; and those 5 cm and 10 cm below the surface at the outer edge of the fire were unaffected. Size, moisture or oil content of the original fruit or seed did not appear to influence whether or not carbonization took place. Temperatures recorded 5 cm below the experimental fires suggest that the carbonization occurred at or before a maximum temperature of 328 °C, and also at lower maximum temperatures (152 °C) that were maintained for long periods. Even when the quantities of a particular wood are controlled, open fires may produce variable underground temperatures and the temperatures below ancient hearths would have been equally variable. We suggest that Cyperaceae (sedge) nutlets, the most numerous fruiting structures in the Sibudu Middle Stone Age archaeobotanical assemblage, occur in the shelter as a result of human activity, subsequent burial, and accidental carbonization when hearths were built directly above the buried nutlets.  相似文献   

12.
Bushfires (landscape fires) are a key Earth system process that affects humans and our societies and economies. In a recent article, we explored the coupling of humans to landscape fire through the lens of human health impacts of bushfire smoke. We noted that such an approach demands recognition of the indirect impacts and costs of bushfires that cannot be captured by simplistic proxies such as deaths directly attributable to a fire front. Evaluation of direct and indirect economic costs of bushfire disasters, and bushfire fire management remains a poorly developed research frontier that demands collaboration of expertise from a broad cross‐section of fields that often have limited experience of collaborating together. The need for such synthetic thinking about fire's place on Earth has spawned the discipline of pyrogeography.  相似文献   

13.
The visceral nature of fire was exploited in the Neolithic and Bronze Age periods in Britain by the burning down of timber buildings and monuments, as well as the cremation of the dead. These big fires would have created memories, perhaps even ‘flashbulb memories’, and this powerful mnemonic aspect of fire was likely of significance to the social and religious lives of individuals, families and communities. This article introduces the Build N Burn concept, where fires are recreated and deployed alongside public talks, performances, experimental archaeology activities and demonstrations by craft specialists to create memorable and informative public events. Three public engagements to date, two on the island of Arran and one in Caithness, both Scotland, are described here. In each case, we constructed replica timber structures inspired by local prehistoric sites, and then burned these down in a free-to-attend public event at dusk, evoking the culmination of a prehistoric festival. Build N Burn has, at its core, the principle of delivering memorable experiences for the public inspired by prehistory, underpinned by research and experiment, using events which draw on cross-sectoral collaboration and working with local communities. This article offers a critical reflection on work to date, and discusses future potential for such activities, utilizing the mnemonic power and transformational potential of fire for public engagement and experimental archaeology.  相似文献   

14.
Four air tanker location-allocation models are considered as tools for suppression of forest fires. The models are tested and compared using forest fire data for Alberta. The results show that fire location patterns can vary considerably over the short term and that not responding to such variation by optimally relocating air tanker groups could be very costly in terms of losses to fire. We argue that an improved location-allocation model can serve as the heart of an optimal air tanker relocation system and suggest the basic requirements for developing such a model.
Quatre modèles localisation-allocation pour avions-citerne sont considérés comme des outils servant dans la lutte contre les incendies forestiers. Les différents modèles sont mis a l'tpreuve et comparts utilisant des données recuillies lors d'incendies forestiers survenus en Alberta. Les rtsultats obtenus montrent que les modèles de localisation de feu peuvent varier considérablement B court terme et que de ne pas se soucier de telles variations par une relocalisation optimale des groupes d'avions-citerne pourait s'avérer trts couteux en terme de pertes dues aux incendies forestiers. Nous soutenons qu'un modtle localisation-allocation amtliort peut constituer le coeur d'un systtme de relocalisation optimal pour avions-citerne et suggérons les conditions fondamentales requises pour le dèveloppement d'un tel modèle.  相似文献   

15.
Accounts of European explorers between 1623 and 1880 indicate that fires were lit by Aboriginal people on Cape York Peninsula in northeast Australia throughout the dry season (May–October). Diaries kept by three generations of pastoralists in the Musgrave area (1913–1952, 1953–1974 and 1976–1992) show that burning activities were largely confined to a two to six week period between May and early August. The timing of burning depended on the amount and date of cessation of wet season rainfall. More rarely, ‘storm‐burning’, burning under hot conditions within a few days of the first heavy rains of the wet season, was undertaken. Long‐term pastoralists felt a responsibility to use fire wisely and had a detailed knowledge of the role of fire in land management. Their decisions to burn were based on the extent of grass curing, and soil and weather conditions, all of which affected the extent of each burn. They used early dry season fires mainly to maintain forage and control cattle movements. Storm‐burns were reputed to control woody weeds, but were used infrequently because of difficulty in controlling their spread and uncertainty as to when the next rains would stimulate new grass growth.  相似文献   

16.
In the geography of risk, vulnerability may be defined as a physical characteristic that describes the tendency of a territory to suffer damage as a result of the occurrence of certain phenomena. According to this synthetic definition, there are two main components of vulnerability in the context of wildland fires. The first is internal, and is related to the effects of fires on the value of the affected assets affected and their capacity for recovery. The second is external, and is related to the characteristics of fires and the ability of society to deal with the hazards of wildland fires. The aim of the present study is to develop an assessment of spatial vulnerability in the context of wildland fires, at a scale appropriate for planning (1/25 000), in a mountainous region of the Spanish Mediterranean coast (Sierra Calderona). The proposed methodology entailed the definition of a synthetic index associated with the management of the risk of wildland fires, which was made up of significant factors such as the difficulty of extinction, the need for forest defence, the need for civil protection, and territorial value. To define and calculate the factors, variables and indicators that reflected aspects of the components of vulnerability (such as exposure, sensitivity, and the capacity to fight fires) were used. These were combined in a hierarchical structure, each having its own cartographical representation. Geographical information systems and multi‐criteria evaluation were then used to provide a successful framework for the analysis of vulnerability in relation to wildland fires. The cartographical outputs of the various components of the index are of particular interest to the planning of certain activities (e.g. forest, wildland fire, and civil protection), all of which are directly involved in the management of risk. In turn, the final synthetic index provides comprehensive spatial information that is useful for spatial planning and also enables the assessment of potential future land use in view of its usefulness in simulations.  相似文献   

17.
Abstract

This paper describes how our understanding of turbulence has grown out of engineering practice and how, in turn, it has modified that practice. This is illustrated by discussions of a number of important combustion phenomena embracing steam and gasoline engines, gas turbines, furnaces, jet fires, fire breathing, and atmospheric explosions.  相似文献   

18.
The pillar of fire was a unique phenomenon that led the Israelites at night through the wilderness for forty years. Many theories have been offered to explain this phenomenon such as it was mythical or metaphorical and never occurred. Other explanations include burning jets of natural gas, a brazier elevated on a pole, volcanic activity, brush fires, lightning, and a comet. The large and controlled shape of the pillar of fire, its appearance only at night for forty years, and its carefully directed path have been explained as miraculous. This article includes a scientific discussion of how the pillar might have been produced, reviews the many theories offered to explain the pillar of fire, and offers several new theories.  相似文献   

19.
A brief factual account of the events associated with bushfires in Australia on 16 February 1983 is provided. General information on the setting for the fires and their immediate impacts on South Australia and Victoria is followed by brief accounts of the major fire areas in South Australia. Finally some questions are raised on the vulnerability of the Australian community to bushfire disasters.  相似文献   

20.
Moran's I, a measure of spatial autocorrelation, is affected by map resolution and map scale. This study uses a geographic information system (GIS) to examine the resolution effects. Empirical distribution of wildland fires in Idyllwild, California, and hypothetical distributions of ordered patterns are analyzed. The results indicate that Moran's I increases systematically with the resolution level. The resolution effects can be summarized by a log-linear function relating the I coefficients to resolution levels. Empirical tests that compare the distribution of fire activity in a vegetation map and in a topographic map confirm the resolution effects observed.  相似文献   

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