Revisiting the half - derivative filter
نویسنده
چکیده
When conjugate gradient (CG) methods are applied to a problem like velocity transform in 2-D, the principal artifact faced is the half-integration waveform (Claerbout, 1993, 1995). Logically, the best filter to suppress a half-integration waveform is the half-derivative filter. In practice, filters like the half-derivative filter have been reported as causing CG residuals to diverge (Lumley, 1994). However, when recently revisiting this approach, I encountered no similar obstacle to convergence.
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تاریخ انتشار 1999