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41.
42.
Urban Seismic Risk Evaluation: A Holistic Approach 总被引:3,自引:4,他引:3
Risk has been defined, for management purposes, as the potential economic, social and environmental consequences of hazardous
events that may occur in a specified period of time. However, in the past, the concept of risk has been defined in a fragmentary
way in many cases, according to each scientific discipline involved in its appraisal. From the perspective of this article,
risk requires a multidisciplinary evaluation that takes into account not only the expected physical damage, the number and
type of casualties or economic losses, but also the conditions related to social fragility and lack of resilience conditions,
which favour the second order effects (indirect effects) when a hazard event strikes an urban centre. The proposed general
method of urban risk evaluation is multi hazard and holistic, that is, an integrated and comprehensive approach to guide decision-making.
The evaluation of the potential physical damage (hard approach) as the result of the convolution of hazard and physical vulnerability
of buildings and infrastructure is the first step of this method. Subsequently, a set of social context conditions that aggravate
the physical effects are also considered (soft approach). In the method here proposed, the holistic risk evaluation is based
on urban risk indicators. According to this procedure, a physical risk index is obtained, for each unit of analysis, from
existing loss scenarios, whereas the total risk index is obtained by factoring the former index by an impact factor or aggravating
coefficient, based on variables associated with the socio-economic conditions of each unit of analysis. Finally, the proposed
method is applied in its single hazard form to the holistic seismic risk evaluation for the cities of Bogota (Colombia) and
Barcelona (Spain). 相似文献
43.
MICHAEL BIRD SUSAN COWIE REA HAWKES† BEN HORTON† COLIN MACGREGOR JIN EONG ONG‡ AILEEN TAN SHAU HWAI§ TEH TIONG SA¶ ZULFIGAR YASIN§ 《The Geographical journal》2007,173(2):103-117
We report the results of a study of the physical characteristics and socio-economic impacts of the Indian Ocean Tsunami of 26 December 2004 on the tourist island of Langkawi, Malaysia. In comparison with many other locations struck by the tsunami, the immediate physical and socio-economic impacts in Langkawi were relatively minor. A detailed survey of the watermark and ground elevations was undertaken in the worst affected area between Sungei Kuala Teriang and Sungei Kuala Melaka. Here, the tsunami reached a maximum elevation of 4.29 m as it crossed the coast, with a maximum flow depth of 2.0 m and a very consistent run-up elevation relative to mean sea level of 300 ± 10 cm. The tsunami inundated inshore areas for 300 m and penetrated inland along creeks for 500–1000 m. Structural damage to buildings was confined to within 50–150 m of the shoreline where about 10% of the houses were completely destroyed and 60–70% suffered significant structural damage. Damage was particularly severe in areas where there was no engineered coastal protection, but while coastal revetments did provide enhanced protection for houses at the waterfront, the coastline in the study area appeared to be more heavily impacted than elsewhere in Langkawi because wave energy was focused on the area by offshore breakwaters built to protect the Langkawi port and airport. Emergency response after the tsunami was rapid and efficient but would have been improved if the local police station had not been rendered inoperative by the first wave, and if a mechanism had been in place to ensure that informal advance warnings transmitted between Phuket (Thailand), Langkawi and Penang (Malaysia) by tourist operators could have been more widely disseminated. 相似文献
44.
农业生产对气候变化的脆弱性研究方法初探 总被引:13,自引:1,他引:13
刘文泉 《南京气象学院学报》2002,25(2):214-220
在总结脆弱性的定义与介绍相关研究方法的基础上,提出了农业生产对气候变化的脆弱性的初步定义、研究思路、指标体系及计算方法,并讨论了区域农业生产对气候变化影响的适应对策应遵循的有关原则。 相似文献
45.
1 IntroductionCoastal areas, with dense population and high urbanization, are highly sensitive to global environmental change. The impacts of coastal environmental changes, such as sea level rise and related disasters exacerbation on socio-economic development of coastal areas, have become a matter of public concern. To study the vulnerable scope and degree of impacts of sea level rise and related exacerbating coastal hazards can provide a scientific basis for lessening the potential losses th… 相似文献
46.
47.
This paper points to the need for seismic risk and vulnerability assessment of infrastructure systems, most notably tall structures and coastal facilities, in Kuwait and other Arabian Gulf countries. Building codes in the region currently lack seismic provisions, despite evidence of a potential threat from large-magnitude earthquakes originating from the southern part of the Zagros fold belt. The historical record of Iranian earthquakes that may have caused significant ground motion in the Gulf region is examined, as are reports of coastal damage from tsunamis. Various specific tasks, expected to constitute research priorities of a Joint Center for Risk Research, a cooperative research program involving Princeton and Kuwait Universities, are outlined. 相似文献
48.
泥石流易损度(危害性)评价是泥石流风险评估的重要组成部分.结合熵值法和突变理论的泥石流易损度评价方法,采用客观的熵值法判断指标间相对重要程度,利用突变级数法计算突变级数值进行评价,方法理论基础牢固且避免了确定指标权重值的弊端.以吉林省和龙市地质灾害调查与区划中的10条泥石流易损度评价实例进行验证,结果表明:数据获取、标准化和评价过程简便,易损度等级以轻度和中度为主的评价结果符合实际情况,该方法经过完善指标体系后可更加合理地应用于实际工作中.因此,基于熵值法和突变理论的泥石流易损度评价方法是可行的、可靠的. 相似文献
49.
Nehal Karim 《Natural Hazards》1995,11(3):247-258
This paper deals with various types of natural disasters which occur very frequently in Bangladesh. Disaster can occur at any time, in any place, in any dimension, and may owe as much to the circumstances as to the scale of the event. With the exception of the man-made disaster of war, famine, fire, pollution, accident and civil strife, the worst disasters follow natural events.Bangladesh is widely known as a land of natural disasters and is highly vulnerable to flood, cyclone and river erosion. By the effects of these disasters the country is now permanently in distress. These disasters have become a regular phenomenon and cause suffering to millions of people of the country since many decades. Besides, it also focuses on policy options concerning disaster management. 相似文献
50.
本文采用类比法和定量化方法对上海宝山区村镇民房震害损失进行了预测。在此基础上,对上海已有的和新建的民房提出抗震对策和措施。 相似文献