Mapping and Evaluation of Underwater Construction Site

• Main Authors: Yu-Jin Lu, 盧禹晉
• Other Authors: Wen-Miin Tian
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/59809398805630516044

碩士 === 國立中山大學 === 海洋環境及工程學系研究所 === 104 === Single-beam, mechanically scanned imaging sonar is an effective system to survey and evaluate the objects in an enclosed or restricted underwater environment. Different from towed array sonar and ship mounted sonar systems, its main functions are to monitor the underwater stationary objects and collect quantitative information, such as dimensions and outer appearance features. Advantages of this sonar system include collecting acoustical images with quality and resolution comparable to optical images to describe the status of stationary objects, and shortening the time of collecting and interpreting images to avoid the danger imposed to human operators and increase work efficiency. In this study, we selected and surveyed the landscape pond in the campus of Sun Yat-sen University to establish the underwater contents of this site by systematic data processing. Compositions of the underwater field were established by the scanning sonar system and post overlaying processing procedure. In this demonstration field, underwater objects were detected include: 3 big circular objects, 5 small circular objects, 1 irregularly shaped object, 9 single-point objects, 1 unknown object, a bridge underwater structure, 4 stairs, slopes of the field boundary, and 4 striped objects. This study could benefit a variety of underwater activities, such as searching for drowning victims, inspecting underwater engineering objects, surveying for underwater archeological investigations as well as delineating underwater pipelines.