چكيده لاتين :
Introduction
Urban vulnerability against natural disasters such as earthquakes is a function of factors or processes which indicates the effectiveness degree or persistence ability of economic, social and urban physical assets in front of vulnerable (Garatwa & Bollin, 2002: 1). In the past two decades, the vulnerability is applied as a basic concept in research relevant to risks and crises and also, developing strategies of reducing risk in local, national and international levels (Rashed and Weeks, 2010: 1). So far, the various models were offered of vulnerability in order to handling ways and different methods in which, vulnerable communities have (Menoni, 2001: 103). A concept which has been clearly stabilized in response to natural and humanistic reactions reveals that natural disasters are of dynamic phenomena that involved people not only as victims, but also as partners and the reformer.
It should be accepted that always percentage of crises are inevitable and in fact, these crises are integral and natural parts of systems' life. However, a large proportion of threats, crises and inflammations are imposed and before occurrence, they should be forecasted and prevented with investigations and their correct management. So, new positions should be adopted about the future, accurate and clear viewpoint should be imagined and predicted about it to prevent managers to be surprised and prevent them to be drowned in the vortex of changes. Thus, alongside with achieve to mentioned objective which has been of the higher importance, this study tried to identify and analyze the vulnerability condition of Bijar city, which was as a first step and a basis of managers' decisions. Neighborhoods of the city which were considered to be physically more vulnerable than other sectors and in addition to material damages, can also cause more personal toll. Therefore, identification of its vulnerabilities can make easier the act to prevent this these damages. This is possible when agents involved in this matter, have adequate knowledge, awareness and ability in crisis management. Enjoying Geographic Information System and using octagon criteria consist of quality of buildings, kind of materials, number of stories, antiquity of buildings, plot's area, the coefficient of occupancy level, pure density of population and land use with fuzzy approach, this study tries to fill the gap and ultimately reduce the damages caused by the occurrence of the crisis. Methodology
This study is applied development research in terms of objective and by descriptive-analytical method was conducted. It means that initially concepts of crisis and crisis management was briefly described, by library method and then, the statistical blocks data relevant to Bijar city in 2011 were used. This means that the weight of each criterion were determined using fuzzy model and after extraction and reclassification of each criterion, the final map and classification of neighborhoods have been prepared, based on the vulnerability in Arc GIS software and fuzzy logic. The used and effective criteria in calculating the vulnerability of neighborhoods are as following: quality of buildings, kind of materials, number of stories, antiquity of buildings, plot's area, the coefficient of occupancy level, pure density of population and land use.
Results and Discussion
The results of this study show that the more population density in city, the more casualties and damages can occur during disasters. Its reasons is the closure of roads and passages and lessen access to safe areas and also, evacuation of the wounded and injured persons. In Bijar city, the Tazeabad neighborhood has more vulnerability in front of likely crisis with the population density 324 persons.
Observing the proximity, land use impact on the reduction of vulnerability. In this study, Farahy and Marzban neighborhoods on the one hand, and Takht-e Sofla and Yarmaje neighborhoods on the other hand, have the less and the most vulnerability.
Regarding quality of buildings, kind of materials, number of stories and antiquity of buildings, it can also be said that the criteria were physical and certainly are effective in vulnerability of the construction. In Bijar city, both Tazeabad and Halvaei neighborhoods with more than 30 year antiquity have more and less vulnerability with the most buildings and 47 buildings respectively, rather than other neighborhoods.
The quality of construction and its implementation depend on various factors in this part, such as the materials used in the structure, importance of the structure, the number of structure's floors, year of construction, construction system, quality control and quality assurance, the situation of insurance industry and generally, depend on the extent of development of the country. The quality of construction's analysis along with analysis of buildings in terms of materials display that Marzban, and Ghale-Takht and Farahi neighborhoods have the most and the less vulnerability, respectively.
Finally, with the involvement of the obtained weights in the normalized data in each of the variables and integrating them, raster layers corresponding to each index was plotted in the Arc Map. Conclusion
According to the obtained results, the factors that have the greatest impact on vulnerability including are quality of buildings, antiquity of buildings, kind of materials, density of population and number of stories respectively. Also, very high vulnerable tissues have been located in the central and southern parts of the city. These areas are matched the old and worn out tissues of the city which in terms of the criteria discussed such as quality of buildings, kind of materials, number of stores, antiquity of buildings, plot's area, the coefficient of occupancy level, pure density of population and land use are not in favorable condition. So, in the event of probable crisis occurrence may have been exposed to the greatest human and financial risks. Among the cities' neighborhoods, Tazeabad and Almasieh neighborhoods are in the higher vulnerability than other neighborhoods. The eastern and northern neighborhoods of the city are in less vulnerability. In recent years, these structures have been built in accordance with the principles of engineering and in terms of indexes considered in this study, they are at an appropriate level.
