A Parallel Adaptive Circumference Method with OpenMP.

The implementation of identifying regional and local gravity fields computing algorithm by adaptive circumference method is achieved in this paper, aiming to the drawback of traditional circumference method in a chosen suitable radius among varies objects. We get suitable radius automatically by the minimum variance of computing point relative to the points on circle in series of set radius, and use the average of regional field value instead of the average of anomaly gravity when calculated point is as the center and to get closer to actual fields in iteration procession. Further, a parallel algorithm based on OpenMP employed multi-core CPU has been presented for high efficiency. Otherwise, the relationship between the number of cores and parallel efficiency is analyzed. The results of theoretical model and actual data show not only our adaptive circumference method can clearly separate abnormal boundary and get accurate abnormity, but also the algorithm is adaptive and has high computational efficiency.