soil water potential was determined for three soil samples (i.e. 0-30, 30-60 and 60-90 cm depth) by the filter paper method (hamblin, 1981) and also for four non-destructive soil samples (i.e. 0-30, 30-50, 50-75 and 75-90 cm horizon) using pressure plate method.  in filter paper method, the filter paper is placed in hydraulic contact with the soil until an equilibrium state is attained in which...

periodic noises are unwished and spurious signals that create repetitive pattern on images and decreased the visual quality. firstly, this paper investigates various methods for reducing the effects of the periodic noise in digital images. then an adaptive optimum notch filter is proposed. in the proposed method, the regions of noise frequencies are determined by analyzing the spectral of noisy...