Mineral industry of Africa in 2005 from 16.1% in 2004. In 2005, the principal mineral targets in Africa were copper, diamond, gold, and platinum group metals (PGM). African countries that experienced the highest levels of exploration activity in 2005 were, in descending order based on the number of exploration sites as compiled by the USGS, South Africa, Burkina Faso, Ghana, and Zambia, but activity took place in a number of other countries. Gold accounted for approximately 51% of reported African exploration projects, diamond accounted for about 14%, copper and PGM each accounted for about 11%, and nickel accounted for 5%. Early stage projects accounted
S transform leads to the result having poorer definition. In the second experiment, two more high frequency bursts are added to crossed chirps. In the result, all four frequencies were detected by the S transform. On the other hand, the two high frequencies bursts are not detected by STFT. The high frequencies bursts cross term caused STFT to have a single frequency at lower frequency. S transform S transform as a time–frequency distribution was developed in 1994 for analyzing geophysics data. In this way, the "S" transform is a generalization of the short-time Fourier transform (STFT), extending the continuous wavelet transform and