When compared to the other inhabitants of Slovakia the Roma are culturally and socially distinct. This is certainly true about their demographic behavior, in particular the age structure of the population, which can be described as a progressive structure of age characteristics by a high proportion of the children and a small proportion of elderly. One of the long-terms demographers' targets is the change of demographic behavior from demographic reproduction to demographic revolution. This process is characteristic by decrease in both mortality and birth rate. The result would be the demographic ageing and the change from the uncontrolled to the planned numbers of the births on the scale of a family structure. Since the Romany population used to be approached as one whole, the used methods failed in the grasping differences in demographic behavior in the Romany settlements with the varying social and cultural standards.
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In this paper, firstly, the far field due to a line source scattering of acoustic waves by a soft/hard half-plane is investigated. It is observed that if the line source is shifted to a large distance, the results differ from those of  by a multiplicative factor. Subsequently, the scattering due to a point source is also examined using the results of line source excitation. Both the problems are solved using the Wiener–Hopf technique and the steepest descent method. Some graphs showing the effects of various parameters on the diffracted field produced by the line source incidence are also plotted.