1.3 The rare but vital phonation studies for prosody researches Since prosody takes the form of suprasegmental features，pitch，duration and intensityare widely investigated．Nowadays most phonetic researches are based on theseacoustic parameters to develop various prosodic models for teaching and voicesynthesis applications．Howeveg some synthesized voices based on these models arefar from satisfactory．If you have ever wached Star Wars，you will be impressed bythose dark warriors’voice．That iS the SO—called“machine voice”because no humanvoice j itter feature is added．Physiological parameters will be probed into for a morenatural voice synthesis outcome． The renowned“source—filter theory”view speech production as a source and filtermodel(Fant 1 960)．Source refers to the glottis signal，which is generated by thevibration of vocal folds，after being“filtered”and resonated by oral cavity wheretongue position differs，sometimes together with nasal cavity resonance whenepiglottis is not fully shut，together with different openness and roundness of the lipshape，whether it is protruding or not，finally becomes our auditory signal．Theacoustic theory defines source(vocal folds’vibration as voice quality)，resonance(vocal tract shape with vowel quality)and radiation(1ip shape with a raise of highfrequency)．The following figure 1．3．1 shows a direct description of the wholeprocess． ……
