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1.
林火行为预测预报专家系统   总被引:3,自引:0,他引:3  
在针对我国大兴安岭林区典型可燃物进行实验的基础上,参考美国北方林火实验室编制的BEHAVE程序中的数学模型,提出了一整套估算森林地表火火行为特征量的表达式。在此基础上,通过交互式窗口技术、字符型汉字技术和专家系统原理,建立了“林火行为预测预报专家系统”。该系统在输入现场可燃物分布特性参数及相应的地形条件和气象条件后,即能迅速预测火蔓延过程中不同时间段的火行为特征量的值。与野外试验的结果对比表明,预测的结果是合理、可靠的。  相似文献   

2.
刘月文  杨宏业  王硕  赵淳 《灾害学》2009,24(3):98-102
森林火灾是一种严重危害人类社会的灾害,它的发生和蔓延将给社会带来不可估量的经济损失和生态环境的严重恶化.若能将森林火灾控制在初发阶段并预测其发展蔓延趋势,将有效的控制森林火灾的进一步蔓延.利用元胞自动机(CA)模拟复杂现象的特点,根据林火燃烧过程中影响因素是否可变,将影响林火燃烧因素分为两大类,设计并实现了适合内蒙古地区林火蔓延模型.  相似文献   

3.
为了提高森林灭火决策和林火管理的效率,直观、科学的林火蔓延模拟成了有用的辅助工具。集成了FARSITE的林火蔓延模拟引擎和基于粒子系统的林火三维可视化方法,研发了林火蔓延三维可视化模拟软件原型系统。系统实现了在逼真的三维虚拟环境中,模拟不同可燃物、地形、气象等因子影响下的林火蔓延过程,预测林火行为,估算过火面积和林火边界。用户可以交互式输入着火点的空间位置、林火影响因子数据,交互式圈定隔离带,模拟、分析不同情境下的林火演化过程。这种形象、动态地表达林火的蔓延过程,可以激发人的直感思维,有利于人们做出合理的灭火方案。  相似文献   

4.
基于GIS的森林火灾现场模拟及其应用   总被引:7,自引:0,他引:7  
分析了基于GIS进行森林火灾现场模拟的可行性,对在ESRI Arc View9x平台上进行森林火场环境模拟、林火蔓延预测和火灾扑救态势标绘与推演的方法进行了研究,并结合开发实例对其实现机制进行了详细的阐述。  相似文献   

5.
基于遥感与Web GIS技术,构建了山火检测及火势蔓延监控平台,主要包括多模型联合的火点检测、基于Rothermel模型的地表火蔓延模拟和基于粒子模拟的三维可视化等功能。系统在多源遥感数据的基础上,联合多项火点检测模型,实现高温异常点的定位,并模拟不同下垫面及气象等因子影响下的火势蔓延过程,进而建立直观的可视化模拟。文章以大同市森林火灾为例,验证系统的可行性,结果表明该系统能够有效检测火点并模拟预测火势蔓延情况,对于提高山区森林防灭火工作水平,减少人员伤亡和财产损失,保护生态环境提供技术支撑。  相似文献   

6.
长白山林区落叶松林可燃物模型及火行为状况   总被引:2,自引:0,他引:2  
在长白山林区不同龄级的落叶松林处设置样地,在样地上设置小样方。采集每个小样方内的死草、活草、凋落物层、半分解层以及1hr,10hr,100hr的杂乱物和灌木,做了可燃物参数的测定。利用Rothermel模型对落叶松林可燃物的蔓延速率、单位面积的热量、火线强度、火焰长度和最大可靠风速进行了计算,得到了比较满意的结果。根据火行为状况,制定了相应的火灾扑救对策。  相似文献   

7.
在火灾蔓延分析的基础上,采取低干预的建筑改造措施对村寨建筑群的火灾蔓延防控具有重要意义。通过对建筑间火灾蔓延路径的判定,建立建筑群火灾蔓延网络的邻接矩阵和蔓延矩阵以确定火灾蔓延风险,进一步结合节点删除法确定改造不同建筑后建筑群的火灾蔓延风险下降率,在此基础上分析了建筑改造的优先级序列并确定了危险建筑。最后将该方法应用于云南某杆栏式村寨建筑群火灾蔓延危险建筑的确定,结果表明:该方法可以有效找出建筑群中对火灾蔓延影响大的危险建筑,且在仅改造少量建筑的情况下,建筑群的火灾蔓延风险便能有可观的下降。  相似文献   

8.
根据模拟复杂系统的元胞自动机,并利用其组成,构建了城市地震次生火灾蔓延模型.通过相关参数的初步量化,模拟了某小区的火灾蔓延,得到了大面积阻火要素,如道路、公园等对阻止火势进一步蔓延的重要作用,及风对火蔓延的重要影响,又考虑了消防扑救对控制火势蔓延的影响,为城市规划和震后火灾扑救提供参考.  相似文献   

9.
考虑城市地震次生火灾发生和蔓延的实际情况,以城市内地震破坏下的建筑物为火灾蔓延的主要载体,从工程应用的角度按不同结构类型给出了次生火灾蔓延参数,并建立了不同类型结构蔓延的临界距离等;考虑地震破坏下和不同风速对燃烧参数的影响,建立了以建筑物为对象的城市地震次生火灾蔓延模型。并以地理信息系统为平台,开发了城市地震次生火灾蔓延模拟系统。该模型的建立可为防御和减轻城市地震次生火灾提供辅助决策,同时对城市日常防火也有一定的参考价值。  相似文献   

10.
隧道纵向通风对火灾规模和火灾蔓延的影响   总被引:3,自引:1,他引:2  
隧道纵向通风一方面会给火源提供大量氧气,扩大火灾规模,增加火灾蔓延的可能性;另一方面又可以带走大量热量,减小火灾蔓延的可能性。目前,这两方面影响的相对重要性还没有被很好地研究。本文对纵向通风对隧道火灾蔓延的影响进行了研究,首先分析了纵向通风对隧道火灾规模的影响,然后利用火灾动力学模拟程序FDS,对不同通风速率及相应火灾规模条件下隧道内车辆间的火灾蔓延进行了数值模拟,得出了不同通风速率条件下火灾蔓延的规律,并提出了控制隧道火灾蔓延的措施。结果表明,增加通风速率能较大地增加货车火灾的热释放速率,当通风速率小于2 m/s时,火灾蔓延的距离随通风速率的增加而增大,当通风速率大于2 m/s时,火灾蔓延的距离受通风速率的影响很小;对于客车火灾,通风对火灾的热释放速率影响较小,并且火灾蔓延的距离随通风速率的增大而减小。  相似文献   

11.
膨胀土地基中大比例模型桩浸水试验研究   总被引:2,自引:0,他引:2  
通过对埋设在膨胀土地基中的一试桩的长时间浸水试验观测,模拟了自然降雨气候条件下单桩位移、沿桩身轴力、侧摩阻力分布、地基胀缩及其时间变化等基桩一系列工作性状和桩-土共同作用规律。试验结果显示:桩顶位移呈现出先下沉后回升并最后趋于稳定的3阶段特征;桩身全长受拉,轴力沿桩身分布呈“波峰”形态。基桩的最大轴力位于桩的中下部,轴力峰值历经由小到大的过程;中性点在浸水过程中,其位置有从桩下部上移的现象;桩侧摩阻力与桩端阻力荷载分担比随时间呈现出先减小后增大并渐趋稳定的3阶段特征。研究结果对膨胀土地基中的桩基设计和施工提供了理论依据。  相似文献   

12.
Managing complex emergency situations is a challenging task, mainly due to the heterogeneity of the partners involved and the critical nature of such events. Whatever approach is adopted to support this objective, one unavoidable issue is knowledge management. In the context of our research project, gathering, formalising and exploiting all the knowledge and information about a given crisis situation is a critical requirement. This paper presents some research results concerning this specific topic: from a theoretical point of view, the generic dimensions of crisis characterisation are defined, while from a technical point of view, we describe a software solution able to collect that knowledge (based on meta‐models and ontologies). This is used to confront the characteristics of the situation (context) with characteristics of the resources (relief system) in order to design a suitable response. Finally, an illustrative example concerning a crash between a tanker truck and a train is described.  相似文献   

13.
The scientific literature regarding HEMS (Helicopter Emergency Medical Service) planning lacks a method for defining optimal sites for helipads that takes into account risk distribution and hospital location. Such a method could minimise overall rescue time in emergency situations. In this paper a method that supports the decisions taken by disaster planners and managers is developed, focusing on the quantification of necessary air resources for the management of some probable calamities. Given a region characterised by a natural and non-natural disaster risk map, along with a comprehensive transport system (also characterised by a risk map), a set of emergency destinations (hospitals), a set of heliports/helipads dislocated on the territory and a number of available HEMS rotorcraft, the aim of the paper is to assess the adequacy of the VTOL/FATO (Vertical Take-Off and Landing/Final Take-Off and Landing Area) system in order to deal with a set of possible emergencies.  相似文献   

14.
Preti A 《Disasters》2002,26(2):99-119
The recent history of Guatemala is interpreted here using an interdisciplinary approach inspired by recent development and conflict studies. The author reflects on his experience in peace-building activities and uses a combination of primary and secondary sources to present the Guatemalan war as a complex political emergency. The first part (a methodological introduction) proposes an analytical framework, taking into account both the root causes and the different functions of violence, in order to achieve a better understanding of contemporary conflicts. In the second and central part of the article, the integrated framework is applied to Guatemala, trying to understand causes and functions of war and negotiation and underlining the existence of structural obstacles to a lasting peace. The conclusions are dedicated to policy implications: if the signing of peace accords represents only a step towards negative peace, the condition for a lasting peace is a strategy for reconciliation and development based on social participation and social justice.  相似文献   

15.
Paul Harvey 《Disasters》1998,22(3):200-217
The paper examines the challenge of rehabilitation from complex political emergencies (CPEs) and identifies a strategy that is characterised as a civil society rebuilding approach. It focuses on Somalia and a case study of a CARE project that aims to build the capacity of local NGOs. The paper argues that civil society in CPEs is simultaneously being undermined and contested by warring parties and emerging after state collapse. The scope of the paper is limited to one case study and that case study examines only a single aspect of civil society: national and international NGOs. The paper therefore presents tentative and preliminary results based on limited research. However, in reviewing the literature and presenting a way of approaching the subject, it aims to suggest a starting-point for developing a theoretical framework for such research. The paper finds that international agencies have tended to focus on civil society institutions simply as conduits for aid money and that this has tended to create organisations which lack downward accountability, are dependent on donors and are not addressing the wider roles for civil society envisaged in the approach. Rebuilding civil society does hold out the promise of giving non-military interests a stronger voice and starting a process of changing the aid delivery culture. Achieving these objectives, however, will be a slow and largely indigenous process and there is a need for lowered expectations about what outside assistance can achieve  相似文献   

16.
Much of the literature on the consequences of natural disasters has focused on their physical and psychological ramifications. Few researchers have considered how the impacts of a natural disaster can influence academic achievement. This study analyses data collected from nearly 300 students at a mid‐sized, private university in the northeast United States to determine if the effects of Cyclone Sandy in 2012 are associated with measures of academic achievement. The findings reveal that experiencing headaches after the event resulted in a higher likelihood of students suffering a loss of academic motivation. In addition, experiencing headaches and a loss of academic motivation were correlated with a lower grade point average (GPA) during the semester in which Sandy made landfall. However, the more direct effects of the superstorm, including displacement and a loss of power, did not have a significant bearing on academic achievement. Lastly, the paper examines the implications for higher education policy and future research.  相似文献   

17.
广东干旱逐日动态监测模型及其应用   总被引:13,自引:0,他引:13  
干旱本质上是一种持续的水份亏缺现象,干旱的严重程度是水份短缺多少及其持续时间长度的函数。借鉴帕默尔(Palmer)旱度模式中的土壤水份平衡概念,采用逐日气温和降水量资料,对土壤有效含水量(分上、下2层)进行了逐日滚动模拟,提出了以下层土壤有效含水量构建逐日干旱动态强度指数(ID),该指数物理意义明确,实时资料可得,能够刻画干旱过程的丰富细节,实现对干旱发生、发展及其强度的逐日动态监测与评估。根据,。的动态变化,精确定义了干旱过程的开始和结束日期,提出了干旱过程强度指数(IDC),实现了对干旱过程的事后定量分析和评估,从而形成了兼具逐日动态监测和后评估功能的一个干旱监测指标体系。  相似文献   

18.
Fiona Fox 《Disasters》2001,25(4):275-289
There is a 'new humanitarianism' for the new millennium. It is 'principled', 'human-rights based' and politically sensitive. Above all it is new. It marks a break from the past and a rejection of the traditional principles that guided humanitarianism through the last century. New humanitarians reject the political naivety of the past, assess the long-term political impact of relief and are prepared to see humanitarian aid used as a tool to achieve human rights and political goals. New Humanitarianism is compelling, in tune with our times and offers a new moral banner for humanitarians to cling to as we enter the new millennium. Or does it? After outlining the key elements of new humanitarianism, including the human rights approach and developmental relief, the paper spells out some of the dangers. The author claims that new humanitarianism results in an overt politicisation of aid in which agencies themselves use relief as a tool to achieve wider political goals. The paper shows how this approach has spawned a new conditionality which allowsfor aid to be withheld and has produced a moral hierarchy of victims in which some are more deserving than others. The paper concludes with a plea for a revival of the principle of universalism as the first step to a new set of principles.  相似文献   

19.
为实现对城市韧性的有效评价,本论文在系统研究国际城市韧性评价体系的基础之上,结合中国城市发展的现状,基于对城市灾后实际恢复过程的系统考察,建立了基于恢复过程的城市韧性评价体系。该评价体系通过解析城市灾后恢复过程的四个阶段:救援阶段(Rescue)、避难阶段(Refuge)、重建阶段(Rebuild)、复兴阶段(Revival),从社区与人口(Community and Population)、政府与管理(Official Organization and Management)、住房与设施(Valuable Housing and Facilities)、经济与发展(Economy and Development)、环境与文化(Renewable Environment and Culture)共五个维度,以62项指标对城市的韧性进行系统分析。这一体系可以简称为城市韧性评价的ReCOVER体系,其中“Re”代表了城市恢复的四个阶段,COVER则分别代表了城市韧性的五个维度。进而以该体系为基础,对我国大陆31个省级行政区域的城市韧性进行了五个维度、四个阶段的实证研究,并对城市韧性的提升策略,给出了分析建议。  相似文献   

20.
为研究下蜀土边坡的地震稳定性,选用天然下蜀土,按照Meymand的相似法则,对一坡高为0.5m、宽度为1.05m、坡角为45°的模型边坡进行了几何相似常数为20的1g大型振动台模型试验详细设计。首先,运用数值模拟的方法确定了模型边坡尺寸适当的边界范围,模型边坡地基厚度、坡脚前缘和坡肩后缘长度均取为0.5m;其次,按照确定的模型几何尺寸设计了符合试验要求的模型箱,其内壁净尺寸(长×宽×高)为1500mm×1050mm×1100mm,属刚性模型箱,且不会与模型边坡发生共振;最后,制定了包括加速度和位移在内的数据量测策略,运用拟静力法求得下蜀土边坡平均屈服加速度为0.561g,综合确定了地震动峰值(PGA)按0.1g、0.3g、0.6g和0.9g的顺序逐级加载的原则,并制定了详细的试验步骤,从而可保障试验得到可靠的结果。  相似文献   

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