As existing descriptions are likely too narrow to reflect a broader range of articulatory variability in Mandarin production, this study is undertaken to explore qualitative and quantitative tongue shape analysis in Mandarin sibilants. Tongue movement data are collected from 18 adult Mandarin speakers producing six sibilants in three vowel contexts. Acoustic information is also analyzed to establish the articulatory–acoustic correspondence. In addition to the common retroflex and bunched shapes, the results discovered a humped shape (e.g., a single, posterior lingual constriction) in most of Mandarin retroflex tokens. This shape is one variant of North American English /r/, but yet identified in Mandarin production. The humped shape adds to the literature and expands existing descriptions of Mandarin retroflex tongue configurations. Despite the shape differences, the general many-to-one articulatory-acoustic mappings also holds true for Mandarin retroflexes. However, while curvature analyses based on Cartesian coordinates significantly differentiated contrastive shapes in retroflex production, these analyses were not equally reliable in separating the alveolar–retroflex distinction, likely due to individual differences. The tongue contour changes in the place contrast were instead quantified by calculations with polar coordinates. The preliminary findings on Mandarin retroflexes are discussed in terms of vocal tract morphology, with possible lip protrusion.

中文翻译：

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普通牙肺泡-反射反射对比的发音舌形分析

由于现有的描述可能太狭窄而无法反映普通话生产中更大范围的发音变化，因此，本研究旨在探讨普通话中定语的定性和定量舌形分析。舌头运动数据是从18位成年普通话讲者收集的，在三种元音环境中产生六种助语。还分析声学信息以建立发音-声学对应关系。除了常见的反折和成束形状外，结果还发现大多数普通话反折令牌中的驼峰形状（例如，单个，后舌缩缩）。此形状是北美英语/ r /的一种变体，但尚未在普通话中找到。驼峰形状增加了文献资料，并扩展了对普通话后向反射舌头形态的现有描述。尽管形状有所不同，但一般的多对一发音-声音映射也适用于普通话反音。然而，尽管基于笛卡尔坐标的曲率分析在反折反射产生中显着区分了对比形状，但这些分析在分离肺泡-反射反射方面并不是同样可靠，这可能是由于个体差异所致。相反，通过极坐标计算来量化舌头轮廓在位置对比中的变化。讨论普通话后屈的初步发现是根据声道形态和可能的嘴唇突出来进行的。尽管基于笛卡尔坐标的曲率分析在反折反射产生中显着区分了对比形状，但这些分析在分离肺泡-反射反射方面并不可靠，这可能是由于个体差异所致。相反，通过极坐标计算来量化舌头轮廓在位置对比中的变化。讨论普通话后屈的初步发现是根据声道形态和可能的嘴唇突出来进行的。尽管基于笛卡尔坐标的曲率分析在反折反射产生中显着区分了对比形状，但这些分析在分离肺泡-反射反射方面并不可靠，这可能是由于个体差异所致。相反，通过极坐标计算来量化舌头轮廓在位置对比中的变化。讨论普通话后屈的初步发现是根据声道形态和可能的嘴唇突出来进行的。