Sohrab Amirian, Masoud Safaeipour, Mr Hassan Hosseini Amini, Mr Hossein Ebadi,
Volume 20, Issue 56 (3-2020)
Abstract
Vulnerability can be considered as an inherent defect in particular dimensions of the urban environment that is susceptible to damage due to its biological and physical characteristics or design features. Therefore, the present study aimed to investigate Ahwaz city structures and fine-tune its vulnerability from a passive defense perspective and to move it towards the future prospects of a safe city. This research is applied in terms of purpose and in terms of descriptive-analytical methodology based on the spatial-model studies approach. The data of this study include 11 educational, fire, administrative, police, power lines, terminals, urban facilities, business centers, roads, urban industries, gas transmission centers and health centers. GIS software was used to analyze the research data. Therefore, distance maps were designed and standardized for measuring the neighboring pattern after identifying the effective layers in the vulnerability and using the Distance tool. The FUZZY OVERLAY tool in ArcGIS software was used for spatial distribution and micro-zoning of Ahwaz vulnerability. The results show that in the section of vulnerability zoning, 29.73% of the city area is completely vulnerable, 29% vulnerable, 21.18% moderate, 13.22% low and 6.85% of the total city area in the state of vulnerability, respectively. There is very little reception.
Mina Mirian, Mostafa Karampoor, Mohamd Moradi, Houshang Ghemi, Behrouz Nasiri,
Volume 23, Issue 68 (4-2023)
Abstract
The purpose of this study is to determine the long-term variations in rainfall data as well as to identify wet and dry periods of 35 synoptic stations in Iran. In order to know the variation of rainfall in studied stations, average maps, coefficient of variation and skewness were drawn. Then, using the Mann-Kendall test, the significance of the trend on each station was tested at 95% confidence level. Finally, wet and dry periods were identified by using 20% high and low extreme rainfall during the 50-year study period. The results show that the general model of the country's regime is that the rainfall levels from the north to the south-east and from the west to the east of the country are reduced. The lowest values of the coefficient of variation and skewness are related to the northern regions especially the Caspian seaside and the highest amounts are in the southern regions, especially in the south and south-east. In general, the results of the Mann-Kendall test show that rainfall data in the seasonal scale, with the exception of several synoptic stations, do not show a significant trend. Most wet periods occur in the spring and the lowest in summer and the highest dry periods occur in the autumn and the lowest in spring. The number of droughts in the cold periods is significant. Also, the frequency of occurrence of dry periods is more than wet periods.
