| 摘要 |
PROBLEM TO BE SOLVED: To locate the position having the absolute error min. value of the required time difference as the best positional identification of the part where solid propagation sound is generated by taking as the basis the intervals of possible speed values for sonic wave propagation for each generation of solid propagation sound and thereupon executing the hyperbolic positional identification method for each speed value at the mentioned intervals. SOLUTION: As development of the cylindrical surface of a pressure vessel, the positions of three sensors S1, S2, S3 are exhibited on a rectangle which has a longitudinal width corresponding to the height H of the cylinder and a crosswise width corresponding to the peripheral circumference U of the cylinder. If it is assumed that the sensir S1 works as the first sensor and has sensed first the signals of sonic waves of a solid propagation sound, the slant range shows the extent where solid propagation sounds are generated. If for example, the propagation sound is generated in position O and the connecting line S3 to the sensor S3 is not the shortest distance d3 to the sensor S3 on the cylindrical surface, the position dislocated from O is determined from the required time difference which is measured by the hyperbolic positional identification method The corrected positional identification dislocates the periphery of the cylindrical surface virtually to Position S3'. In the same manner, all points on the surface are subjected to positional identification for S2' and S3'. |
