Journal of the Japan Society of Erosion Control Engineering, Vol.56,No.3,2003
A study on the method of critical line in the each slope using data envelopment analysis

Soichi KAIHARA, Masao ARAKAWA, Hiromi TETSUGA, Takeharu SATO, Mitsuru MAEDA, Hirotaka NAKAYAMA, Kohei FURUKAWA

Abstract
The Sediment Disasters Prevention Law enacted in April 2001, and establishment of warning and evacuation schemes at sediment]related]disaster prone areas is now an urgent necessity. Slope]specific risks are not taken into account in the conventional critical lines for failure occurrence, which are set based only on the relationship between rainfall and slope failure. It is therefore difficult to set critical lines precisely in this approach. To solve this problem, the authors propose a new approach to setting critical lines for failure occurrence by assigning risk to each slope using the rough set theory and taking the risk of each slope into account through data envelopment analysis. The effectiveness of the new approach is demonstrated through a comparison of precision with the conventional approach of linear critical lines.

Key words:data envelopment analysis, slope failure, critical line, rough sets