Acoustic analysis of the vocal tract during vowel production by finite-difference time-domain method
Acoustic analysis of the vocal tract during vowel production by finite-difference time-domain method
复制标题
DOI：
10.1121/1.3502470
复制
发表时间：
2010-12-01
影响因子：
2.4
通讯作者：
Kitamura, Tatsuya
中科院分区：
文献类型：
--
作者：
Takemoto, Hironori;Mokhtari, Parham;Kitamura, Tatsuya
声道的形状是三维复杂的。为了准确的声学分析，在本研究中引入了时域有限差分法。通过这种方法，五个日本元音声道的传递函数计算三维重建的磁共振成像（MRI）数据。计算出的传递函数进行了比较，从声学测量声道的物理模型，精确地构建从相同的MRI数据。计算的传递函数与测量的高达10 kHz。梨状窝，会厌谷，和齿间间隙的声学效果也进行了检查。它们通过产生下降而引起光谱变化。梨状窝的变化量很大，而其他两个几乎可以忽略不计。梨状窝和山谷产生的频谱下降的所有元音。梨状窝的凹陷频率几乎是稳定的，而谷的频率在元音之间变化。齿间空间产生非常小的频谱下降低于2.5 kHz的高和中元音。此外，口腔内的横向共振产生小的频谱下降超过4千赫的低元音。(C)2010年美国声学学会。[DOI 10.1121/1.3502470]
The vocal tract shape is three-dimensionally complex. For accurate acoustic analysis, a finite-difference time-domain method was introduced in the present study. By this method, transfer functions of the vocal tract for the five Japanese vowels were calculated from three-dimensionally reconstructed magnetic resonance imaging (MRI) data. The calculated transfer functions were compared with those obtained from acoustic measurements of vocal tract physical models precisely constructed from the same MRI data. Calculated transfer functions agreed well with measured ones up to 10 kHz. Acoustic effects of the piriform fossae, epiglottic valleculae, and inter-dental spaces were also examined. They caused spectral changes by generating dips. The amount of change was significant for the piriform fossae, while it was almost negligible for the other two. The piriform fossae and valleculae generated spectral dips for all the vowels. The dip frequencies of the piriform fossae were almost stable, while those of the valleculae varied among vowels. The inter-dental spaces generated very small spectral dips below 2.5 kHz for the high and middle vowels. In addition, transverse resonances within the oral cavity generated small spectral dips above 4 kHz for the low vowels. (C) 2010 Acoustical Society of America. [DOI: 10.1121/1.3502470]