著者

Kenji Ishikawa Yasuhiro Oikawa Yoshio Yamasaki

出版者

一般社団法人 日本音響学会

雑誌

Acoustical Science and Technology (ISSN:13463969)

巻号頁・発行日

vol.36, no.5, pp.408-418, 2015 (Released:2015-09-01)

参考文献数

23

被引用文献数

1

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Light propagating through a sound field is affected by variations in the density of the medium caused by sound. Therefore, acoustical measurements using light have been studied. The popular measurement methods use the phase shift of the transmitted light. Because they detect integrated acoustical quantities along the optical path of the detected light, time and effort are required to measure the quantities at a single point. On the other hand, single-point acoustical particle velocity measurement by light scattering has been proposed. Using light scattering enables the measurement of non-integrated quantities because the scattered light includes only the acoustical information at a scattering point. However, a method of non-invasive sound pressure measurement at a single point in a free field has not been established. This paper proposes sound pressure measurement at a scattering point, in which the light scattered by particles in the sound field is observed. The intensity of light scattered in the sound field indicates the sound pressure because the intensity of the scattered light is proportional to the density of scatterers. The theory of light scattering by sounds is formalized, and sound measurement experiments with light scattering are also conducted using water drops and air particles as scatterers.

著者

Yusuke Torikai Dai Kuze Junko Kurosawa Yasuhiro Oikawa Yoshio Yamasaki

出版者

一般社団法人 日本音響学会

雑誌

Acoustical Science and Technology (ISSN:13463969)

巻号頁・発行日

vol.36, no.6, pp.500-506, 2015 (Released:2015-11-01)

参考文献数

15

被引用文献数

1

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We investigated a new communication-aid system focused on bone-conduction through a tooth, for listening to and recording voices. In this paper, we developed a tooth-conduction microphone (TCM) and evaluate the articulation of tooth-conducted voice (TCV). Because the TCM has the shape of one's dental mold, it is wearable like a mouthpiece. Moreover, it can extract tooth vibration during phonation as TCV. To evaluate articulation of TCV, we adopted monosyllable articulation for subjective assessment and linear predictive coding cepstral distance for objective assessment. The results of articulation show that TCV is not sufficiently clear compared to air-conducted. However, it is confirmed that TCV is robust to environmental noise because the accuracy rate is not decreased when the TCV is recorded under high ambient noise.

著者

Yoshio YAMASAKI Kazuyuki MAEKAWA

出版者

Japan Society for Bioscience, Biotechnology, and Agrochemistry

雑誌

Agricultural and Biological Chemistry (ISSN:00021369)

巻号頁・発行日

vol.42, no.9, pp.1761-1765, 1978 (Released:2008-11-27)

参考文献数

21

被引用文献数

14 47

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A peptide fraction with a delicious taste was isolated from the gravy of beef meat. By successive application of gel filtration with Sephadex G-25, chromatography on an ion exchange resin (Dowex 50×4), and paper electrophoresis, the peptide was purified. The amino acid sequence of the purified peptide was determined by Edman degradation for N-terminal and Cpase A method for C-terminal sequence. As a result, the primary structure of the peptide was proposed as follows; H-Lys-Gly-Asp-Glu-Glu-Ser-Leu-Ala-OH.