Effects of Long-Term Ageing on Speaker Verification

Abstract. The changes that occur in the human voice due to ageing have been well documented. The impact of these changes on speaker verification is less clear. In this work, we examine the effect of long-term vocal ageing on a speaker verification system. On a cohort of 13 adult speakers, using a conventional GMM-UBM system, we carry out longitudinal testing of each speaker across a time span of 30-40 years. We uncover a progressive degradation in verification score as the time span between the training and test material increases. The addition of temporal information to the features causes the rate of degradation to increase. No significant difference was found between MFCC and PLP features. Subsequent experiments show that the effect of short-term ageing (<5 years) is not significant compared with normal inter-session variability. Above this time span however, ageing has a detrimental effect on verification. Finally, we show that the age of the speaker at the time of training influences the rate at which the verification scores degrade. Our results suggest that the verification score drop-off accelerates for speakers over the age of 60. The results presented are the first of their kind to quantify the effect of long-term vocal ageing on speaker verification.

Hot Spring Water Traced Back to Fluid Released from a Dehydrating Slab

日本温泉科学会第71回大会、特別講演ⅡSince 2003, we have begun a geochemical research for hot spring derived from slabdehydrated fluid and have published results of the research as papers from 2005. In addition, we were working together with researchers in metamorphic petrology and the effort contributed to development of a research theme in the interdisciplinary field and fostering of younger researchers. In a special lecture at the 67th annual meeting of the Japanese Society of Hot Spring Sciences held in September 2018, the author spoke overview our research, and furthermore, he presented two related sub-research subjects which had been introduced by previous oral presentations at several academic conferences. In this paper, the results of the sub-researches including new findings obtained during the preparation process of this oral presentation will be written down. 私たちは 2003年よりスラプ脱水流体由来の温泉の地球流体化学的探索を始め，その研究成果を論文等として公表し (2005年-2016年）．その一方で，変成岩岩石学との分野横断研究を行って新たな研究課題の創始と若手研究者の育成にも貢献した. 2018年 9月に開催された日本温泉科学会第 67回大会における特別講演において．これまでの私たちの研究の概要を紹介するとともに．学会での口頭発表にとどまっている関連の 2つのサプ研究課題についても発表した．この論文には．今回の発表の準備過程で手にした新たな知見を含むそのサプ研究の成果を書き留める