“…During the last two decades numerous algorithms have been studied and discussed in literatures, such as convolution [16], differentiation [17], Fourier transforms [18], neural networks [19], genetic regression [20], principal component analysis and partial least squares [21], Kalman filtering [22,23], and wavelet transforms [24], all of which have been reviewed particularly by van Veen and de Loos-Vollebregt [25].…”