Determination of the level of seismic hazard in Yogyakarta using fuzzy simple additive weighting method

Abstract

This study aims to obtain a mapping of seismic hazard vulnerability of Special Region of Yogyakarta (DIY) using the Fuzzy Simple Additive Weighting (FSAW) method. This mapping is serves as an act of mitigation for earthquake disasters to reduce the risk of earthquake disasters and minimize fatalities or losses in earthquake-prone areas. The factors used construct the mapping of earthquake-prone areas in Yogyakarta are social, physical, and economic vulnerabilities. Each factor has several variables. The data of this research were taken from the Central Bureau of Statistics (BPS) and the National Disaster Management Agency (BNPB) of the Special Region of Yogyakarta from 2014 to 2017. The FSAW method was used to determine the level of seismic hazard for each sub-district in DIY with a high, medium, or low vulnerability category. The steps taken in the FSAW method are (1) performing fuzzification for each variable, (2) normalizing, (3) determining the weigh of each variable, (4) determining the classification of the result; whether it is categorized under high, medium, or low level. The result from this study is a map that shows areas in each district of Special Region of Yogyakarta with high, medium, and low seismic vulnerability. Based on the social, economic and physical vulnerability factors, it was found that every sub-district in Yogyakarta City were categorized under the high-level vulnerability, while the sub-districts in Bantul, Gunungkidul, Kulonprogo and Sleman Regencies had the average level of medium.