Basic Research on the Phonetic Status of Vowel Devoicing and Accent in Metropolitan Dialect

东京及其邻近地区使用的语言可以定义为大都会方言。这项研究的目的是描述尚未完全描述的、但被普遍认为是标准日语的大都市方言。在这种情况下，研究的重点是元音和重音的去声。元音清音在日语中不是音素成分，但却是标准日语的重要语音特征。元音清声的基本条件已经明确，但实际情况还不得而知。对冲绳的竹井话、岩手县的盛冈话、兵库县的西瓦基话进行了调查。本研究利用700多个语料进行田野调查，研究结果如下：1.在都市方言中，元音去声的程度因信息者的不同而不同。几乎没有任何知情者去发音‘sushi’这个词的元音。2.去元音会影响重音核心的位置。研究表明，在单词“fuku”(吹音)和“fuku”(擦音)的情况下，元音清音不会影响重音核心，但在单词“cuku”(到达)和“cuku”(鱼叉)中，重音核心移动，许多信息者发音相同。3.清音辅音之间的低元音清音程度据报道有所降低，但在像yamanotesen这样的词中观察到了低元音的年轻清音。4.元音清音和音节非鼻辅音之间的关系不明确。“nisshimbashi”和“nishimbashi”等词对的区别并不明确，需要更多的研究。人们从声学语音学的角度进行研究，但也有必要利用许多研究项目来研究许多信息来源。

The language spoken in Tokyo and neighboring area can be defined as Metropolitan dialect. This research aims to describe the Metropolitan dialect which is not yet fully described, while it is generally accepted as standard Japanese.In this occasion, the focus of the research was put on the devoicing of vowels and accent. Vowel devoicing is not phonemic element in Japanese, but it is known as important phonetic characteristic of standard Japanese. The basic condition of vowel devoicing is made clear already, but actual state has been left unknown.Surveys were made on Taketomi dialect in Okinawa, Morioka dialect in Iwate, and Nishiwaki dialect in Hyogo. Field work researches were carried out using over 700 items, which brought following results.1.In the Metropolitan dialect, the degree of vowel devoicing varies depending on the informant. There are hardly any informants who devoice the vowel of the word ‘sushi'.2.Vowel devoicing affects the position of accent cores. It was made clear that in the case of the word pair ‘fuku' (blow) and ‘fuku' (wipe), vowel devoicing does not affect the accent core, but in the pair ‘cuku' (arrive) and ‘cuku' (spear), the accent core moves and many informants pronounce them identically.3.The degree of devoicing on low vowels between voiceless consonants are reported to decrease, but in the young devoicing of low vowels were observed in the words such as ‘yamanotesen'.4.The relationship between vowel devoicing and syllabic non-nasal consonants is obscure. Distinction between the word pair such as ‘nisshimbashi' and ‘nishishimbashi' is not clear and need more study.Researches are being done from the viewpoint of acoustic phonetics, but it is also necessary to study many informants using many research items as this research.