ANALYSIS OF DEBRIS FLOW UNDERGROUND SOUND BY WAVELET TRANSFORM - A CASE STUDY OF EVENTS IN AIYUZIH RIVER — IJEGE
 
 
You are here: Focus and scope Issues from 2005 to 2017 5th International Conference on Debris-Flow Hazards "Mitigation, Mechanics, Prediction and Assessment" Topic 6 - Debris-flow Monitoring and Alert Systems ANALYSIS OF DEBRIS FLOW UNDERGROUND SOUND BY WAVELET TRANSFORM - A CASE STUDY OF EVENTS IN AIYUZIH RIVER
Document Actions

ANALYSIS OF DEBRIS FLOW UNDERGROUND SOUND BY WAVELET TRANSFORM - A CASE STUDY OF EVENTS IN AIYUZIH RIVER



Abstract:
Since 2002, the Soil and Water Conservation Bureau, which is responsible for the conservation and administrative management of hillside in Taiwan, has been cooperating with Feng Chia University. Together, they have successively carried out the establishment and maintenance of 17 debris flow monitoring stations over the Taiwan and 3 mobile debris flow monitoring stations. Geophone is one of the most important sensor to detect whether debris flow occur or not. The wavelet transform is employed in this study to analyze the underground sound of debris flows obtained from the geophones. Three debris flow events observed at Shenmu monitoring station (Nantou County) on July 2, 2004 and on August 8, 2009 are selected as examples. It is found that the wavelet transform not only can separate ambient noise effectively but also can be used to determine the beginning time of debris flow event. In order to estimate the magnitude of debris flow event, a so-called wavelet accumulated energy indicator is proposed. When debris flow occurs, the wavelet accumulated energy will increase. So the wavelet accumulated energy’s threshold value is double of normal value. It can be used to determine the occurrence of debris flow and to estimate its magnitude.

Authors:
Yao-Min Fang - Geographic Information System Research Center, Feng Chia University, Taichung 40724
Ti-Min Huang - Geographic Information System Research Center, Feng Chia University, Taichung 40724
Bing-Jean Lee - Department of Civil Engineering, Feng Chia University, Taichung 40724
Tien-Yin Chou - Department of Land Management, Feng Chia University, Taichung 40724
Hsiao-Yuan Yin - Chief Department Officer, Slopeland Monitoring Section, Monitoring and Management Division, Soil and water conservation Bureau, Council of Agriculture, Executive Yuan
Keywords
Geophone, debris flow underground sound, wavelet transform, wavelet energy accumulated indicator.
Statistics