Does semantic stress have effect on duration and pitch patterns of prosodic words in presenters´ speech?

Stress is a main prosodic feature; it becomes more and more important in speech recognition, speech synthesis and understanding, especially in the spontaneous speech. This paper is intended to analyze whether the semantic stress has effect on pitch and durational pattern of prosodic word in broadcast presenters´ speech. The research results shows that the stresses will not make a fundamental difference to change the durational pattern most of which still keep a long-tail duration pattern within prosodic words. Whereas, stresses can influence the duration of some particular syllables, for instance, in some four-syllable prosodic words, the durational pattern changes to a long-head pattern if its first two syllables are accented. On pitch pattern, there are different prominences because the different syllable is accented within prosodic word. Thus the pitch feature of stressed prosodic words manifests more complex than that of the non-stressed ones. To some extent, we can suggest that the pitch pattern of stressed prosodic words has been changed by semantic stress.