| Abstract [eng] |
The dissertation focuses on the acoustic base of long vowel tones in Lithuanian and Latvian dialects (the material under analysis comes from two dialect areas, namely the subdialects in the Telšiai in the northern Samogitia, and the central Latvia). The aim was to determine what acoustic features play the key role in tone contrastivity in each of the dialects, and what differences and similarities between these key features are. The group of quantitative features analysed and compared in the present study comprised pitch, duration, and intensity of the long vowels pronounced along with the tones. The methods employed in the study (i.e. mathematical, statistical, graphic, analytic, and others) indicated correlative relations between the acoustic features under comparison, thus becoming a reference point for a supposition of similarity between tone contrastivity in Lithuanian and Latvian languages. Among the most important correlations was the direct dependence between the long vowel duration and pitch parameters (range and mean rate of change), which suggests that the increasing vowel duration is inseparable from the (relative) rate of pitch change. With the addition of a supplementary mathematical parameter (which is obtained by multiplying vowel duration by the relative value of pitch parameters) and the calculation of data dispersion enabled by it, it became clear that there is a statistically significant difference between acute and circumflex tones (the pitch of the latter changes more slowly) in the northern Samogitian subdialect in the Telšiai, and between the sustained tone and the other two (i.e. the broken and the falling tone, in both of which the change of pitch is more intense) in the central Latvian dialect. This latter universal phonetic feature, identified in this study, supports the core conclusions of the present dissertation and opens the prospect of its positive contribution to perfecting speech technologies as well as to other similar research into other tone languages. |
