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지하매설 플라스틱 배관의 누수지점 추정을 위한 창함수 비교 연구

Comparison of Window Functions for the Estimation of Leak Location for Underground Plastic Pipes

  • 이영섭 (인천대학교 임베디드시스템공학과)
  • 투고 : 2010.04.12
  • 심사 : 2010.05.04
  • 발행 : 2010.06.20

초록

It is widely known that the leak locating of underground plastic pipelines is much more difficult than that of cast iron pipelines. The precision of the leak locating depends upon the speed of leak signal and the time delay estimation between the two sensors on the pipeline. In this paper, six different windowing filters are considered to improve the time delay estimation especially for the plastic pipelines. The time delay is usually estimated from the peak time of cross-correlation functions. The filtering windows including rectangle, Roth, Wiener, SCOT, PHAT and maximum likelihood are applied to derive the generalized cross-correlation function and compared each other. Experimental results for the actual plastic underground water supply pipeline show that the introduction of the filtering windows improved the precision of time delay estimation. Some window functions provide excellent leak locating capability for the plastic pipe of 98 m long, which is less than 1 % of the pipe lengths. Also a new probabilistic approach that the combinations of all results from each filtering window is suggested for the better leak locating.

키워드

참고문헌

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