PhD (Tshivenda) / Senthara ya M.E.R. Mathivha ya Nyambo dza Afrika kha Vhutsila na Mvelele / Tshivenḓa is one of African languages spoken in the Northern parts of South Africa and some parts of Zimbabwe. This proposal focuses on a study of selected phonological processes involving Tshivenḓa vowels. The Tshivenḓa phonological processes involving vowels under this study include vowel elision/deletion, vowel epenthesis, vowel coalescence, vowel nasalisation, vowel harmony, vowel raising and glide formation. In this regard, consonants are not part and parcel of this study. Furthermore, the study enriches the phonology of Tshivenḓa with more phonological processes thereby adding on the existing literature. The study also attempts to motivate and encourage Tshivenḓa speaking people and those who are interested in the language to have a clear understanding of phonological processes which occur in Tshivenḓa. The theoretical framework underpinning this study is the Optimality Theory (OT). The study will be carried out through phonological analysis, that is, field work and word list. Secondary sources will also be used for data collection.

This study investigates phonetic and phonological factors which influence the degree of vowel-to-vowel coarticulation in Korean and English, especially around palatalization rules. Two phonetic factors and two phonological factors were examined in investigating the degree of anticipatory or carryover coarticulation in VCV sequences. The phonetic factors were the intervening consonants (alveolar stop vs. (alveo)palatals), and the second vowels (/i/ vs. /a/); the phonological factors were the effect of palatalization, and the lexical status of palatalization (lexical vs. postlexical palatalization). Ultrasound imaging techniques and F2 measurements are employed to see how much further front the articulation of V1 in V1CV2 sequences is due to influence of V2 across the consonants. Ultrasound images of vowels and their F2 values were quantified and statistically analyzed with ANOVA.First, it was found that V1 in V1CV2 sequences in Korean was articulated further front when intervening consonants were palatals than when they were alveolars, while there was no difference in frontness of V1 between two consonantal conditions in English. This indicates that Korean palatals are a stronger barrier to vowel-to-vowel coarticulation, while English alveopalatals are not. Next, V1 in both languages was articulated further front when V2 was /i/ than when V2 was /a/. Third, we had striking findings that palatalization rules caused stronger vowel-to-vowel coarticulation than in nonpalatalized words. Results showed that V1s were articulated further front across derived palatals than across underlying palatals in V1Ci sequences. Last, it was determined that V2 was articulated further front in words which underwent postlexical palatalization than in words which underwent lexical palatalization. Such findings indicate that postlexical palatalization causes greater gestural overlap than lexical palatalization, showing stronger degree of coarticulation.Based on the experimental results that phonetic details such as the degree of vowel-to-vowel coarticulation are highly conditioned by the lexical status of palatalization as well as the application of palatalization, I suggest a unified model of phonology and phonetics, using feature-and-gesture based OT frameworks. Second, I follow the proposal that abstract intergestural timing relations should be incorporated into phonological representations either in the input or output (Cho 1998, Gafos 2002, Yun 2005b).

No description available.

In Malayalam, a Dravidian languages spoken in India, there is a contrast in vowel length, as in [ka[retroflex lateral approximant]i] 'game' and [ka:[retroflex lateral approximant]i] 'goddess of death'. This vowel length contrast is the basis for any theory of stress placement in Malayalam. A listener acceptability study was performed to determine how acceptable vowel duration variation was to native speakers. It was found that listeners prefer a long vowel to have a longer duration than a short vowel. It was also found that listeners only accepted short vowel reduction and/or deletion when it was next to a vowel of contrasting length. Implications of these findings are discussed. A listener acceptability study was performed to determine how acceptable vowel duration variation was to native speakers. It was found that listeners prefer a long vowel to have a longer duration than a short vowel. It was also found that listeners only accepted short vowel reduction and/or deletion when it was next to a vowel of contrasting length. Implications of these findings are discussed. / text

No description available.

A dynamic mechanical model of the human larynx and vocal tract has been developed to investigate its acoustic and fluid dynamic behaviour during sustained vowel production. The model comprises a cylindrical duct, open at one end, with a controlled air flow introduced at the other. The flow entering the duct is modulated by the periodic opening and closing of pair of electro-mechanically driven shutters. Far field measurements of the radiated pressure have shown that the model generates sound which has a spectral distribution that corresponds, at low frequencies, to that of an open vowel. However the spectral amplitudes were somewhat lower than voiced speech sounds normally generated at the same low rate. The addition of an orifice plate to reduce the duct exit area was found to increase the level of the radiated sound and to modify the spectral distribution somewhat. The flow distribution throughout the model duct has been measured using hot wire anemometry. The velocity distribution measured in the model was found to correspond to that measured in the oral cavity of four live subjects. Calibrate pressure measurements at the duct wall have been used define the associated pressure field within the duct. The pressure distribution found within the model corresponded to that measured in vivo by other researchers. The velocity within the duct was shown to be associated with contributions from three separate velocity fields, the rotational acoustic particle velocity and a rotational velocity field due to vortex development at the exit to the shutters. It was shown that the rotational velocity disturbance convected along the duct at approximately the local mean flow velocity. Comparison of prediction with measurement of the radiated sound fields showed that the presence of a rotational velocity field at the duct exit made a significant contribution to the radiated sound pressure level. A discussion is included as to whether acoustic sources, associated with the rotational flow, exists at area discontinuities in the vocal tract in addition to the generally accepted acoustic source due to fluctuating mass flow at the glottal exit. The influence of the Rotheberg Mask on the flow and acoustic behaviour of the model was investigated in some detail. Measurements show that the velocity field was almost unaltered, but the fluctuating pressure amplitudes were greatly reduced. Corresponding reductions were found in the radiated acoustic power with further reductions apparently due to the suppression of the rotational flow sources by the mask.

This thesis aims to provide a principled account of the distribution of 'tense'/'lax', and 'high/low' vowels in vowel harmony systems. It is based on the principles and parameters of Government Phonology in which variation is accounted for by possible combinations of parameter settings. To explain variation in 'tense/lax' and high/low' distribution, I exploit the interaction of the parametric aspects of three universal mechanisms: Licensing Constraints, Head-licensing (both Kaye (1993b)), and the Complexity Condition (Harris (1990a)). The type of language data this thesis seeks to account for has received some attention in the phonological literature, in terms of other frameworks as well as Government Phonology. These treatments are evaluated here. Two of the three main tools employed are recent inclusions in Government Phonology. The role of Licensing Constraints as parameters on element distribution is explored in the context of the principles and parameters drawn on in this thesis. Licensing Constraints have certain repercussions for other aspects of the theory. These are explored in detail. Licensing Constraints interact with Head-Licensing, a principle explaining 'ATR' distribution. Additionally, I claim that some aspects of Head-Licensing are subject to parametric variation. The possible combinations of parameter settings are presented, illustrated with a variety of language data. The Complexity Condition is claimed to apply parametrically in processes taking place at the level of nuclear projection. As Head-Licensing occurs at this level, some languages are expected to enforce the Complexity Condition. I examine cases where this takes place, and the variety of strategies employed by languages for its maintenance. Finally, I explore how the interaction of Licensing Constraints, Head- Licensing and the Complexity Condition might provide a unified account of harmony processes traditionally described in terms of 'raising', 'lowering', '+ATR' and '- ATR'. I evaluate, and propose analyses of some cases from the literature.

One family of theories regarding vowel perception suggests onset and offset formant-frequencies are important for identification and that the shape of the transitions themselves are not otherwise perceptually important. The present study determined just-noticeable-differences in deviations from linear formant trajectories. Diphthong-like stimuli were manipulated by inserting a point of inflection into the otherwise linear transition. Several parameters were manipulated including vowel duration, location of the inflection point in time, and fundamental frequency. Data from the first experiment indicate that listeners are largely insensitive to deviations from linearity of formant trajectory but that large enough deviations could eventually be detected. The size of these deviations seems dependent on the range of onset-offset formant frequencies. However, a second experiment in which only the first half of stimuli was presented thereby affecting the frequency range of the stimuli, gave different results. Results from these experiments along with several hypotheses are presented.

No description available.

This work examines the link between low-level cortical acoustic processing and higher-level cortical phonemic processing. Specifically, using functional magnetic resonance imaging, it looks at 1) whether or not the vowels [ɑ] and [i] are distinguishable in regions of interest defined by the first two resonant frequencies (formants) of those vowels and 2) whether or not that neural discrimination ability changes based on anatomical region. The formant-frequency based regions of interest are found to respond differentially to [ɑ] and [i] with the response to [ɑ] statistically significantly greater than the response to [i] in the averaged [ɑ] formant-frequency based region. Unexpectedly, the response to [i] is numerically but not statistically significantly greater than the response to [ɑ] in the averaged [i] formant-frequency based region. Additionally, there is not a significant interaction of this pattern with anatomical region, although early cortical auditory regions appear to show the pattern while later ones do not. Further investigation into the results leads to the hypotheses that they could be due to task-specific neural processing strategies and that the link between lower and higher-level cortical auditory processing is more complex than originally hypothesized.