日本音響学会誌
Online ISSN : 2432-2040
Print ISSN : 0369-4232
35 巻, 1 号
選択された号の論文の8件中1~8を表示しています
  • 子安 勝
    原稿種別: 本文
    1979 年 35 巻 1 号 p. 1-2
    発行日: 1979/01/01
    公開日: 2017/06/02
    ジャーナル フリー
  • 大家 左門, 竹内 龍一
    原稿種別: 本文
    1979 年 35 巻 1 号 p. 3-10
    発行日: 1979/01/01
    公開日: 2017/06/02
    ジャーナル フリー
    Acoustical properties of a thin porous plate vibrating in a fluid were investigated theoretically. The wave equations for the porous plate and for the fluid layer in the plate were derived by taking account of the interactive effects between the solid frame of the vibrating porous material and the surrounding fluid. Equations of motion obtained for both cases were represented in simplified forms containing only the sound pressures and the particle velocities on the both side surfaces of the plate. Using the above mentioned results, we executed some numerical calculations on the sound absorbing characteristics of the porous plate located near a rigid wall. And it is discussed on the coupling effects between the motions of the porous plate and of the fluid layer.
  • 宝川 幸司, 吉川 昭吉郎
    原稿種別: 本文
    1979 年 35 巻 1 号 p. 11-20
    発行日: 1979/01/01
    公開日: 2017/06/02
    ジャーナル フリー
    This paper concerns with a temperature independent oscillator over wide temperature range, constructed by using parallel connected multiple resonators with different temperature characteristics. The principles of temperature compensation, an equivalent circuit of SAW resonator, and the limit of temperature compensation using SAW devices were clarified theoretically and verified experimentally. Using resonators deposited on two kinds of rotated Y cut Quartz, the SAW temperature compensated oscillator were constructed experimentally, the temperature variation of oscillation frequency of which was 2*10^<-6> over 60℃ or more temperature range. The trimming method of resonant frequency using series capacitance, which is theoretically defined and experimentally verified is also described.
  • 井 研治, 池谷 和夫
    原稿種別: 本文
    1979 年 35 巻 1 号 p. 21-28
    発行日: 1979/01/01
    公開日: 2017/06/02
    ジャーナル フリー
    This paper describes about some characteristics of voice babble statistically from the viewpoint of the number of extraneous talkers. The probability distribution function proposed by Davenport was extended to W_n(x) where there are n simultaneous talkers each creating the same conversational speech level, and x is the speech amplitude normalized to have an rms value to unity. In case of n being larger than 4, W_n(x) was estimated on the basis of bilateral exponential distribution. Each estimated value provides a good apporoximation to measured one. Level distributions of overlapped speech were also measured after normalizing the value of equivalent noise level L_<eq>. The reception of monosyllabic words presented to a single ear with a voice babble was compared. These results indicate that either interfering talker or interfering speech level increases, the percentage articulation decreases. Another intelligibility measurement against artificially fluctuated complex tone agrees with the one by voice babble, so it can be concluded that the voice babble exhibits a tendency like an overlapped vowels.
  • 菊池 年晃
    原稿種別: 本文
    1979 年 35 巻 1 号 p. 29-35
    発行日: 1979/01/01
    公開日: 2017/06/02
    ジャーナル フリー
    The sound velocity in the mixtures of RTV silicon rubber and various powders is a function of only the concentration at low frequency. In this range, the sound velocity in the RTV silicon rubber compounded with low density powder is larger than that in pure RTV silicon rubber and increases monotonically as the concentration of the mixture increases. The sound velocity in the RTV silicon rubber compounded with high density powder such as zinc, iron, and wolfram, decreases with the concentration. Then the range of measured sound velocity for the various mixtures is between 730 and 1300 m/sec. The specific acoustic impedances of the mixture compounded with high density powder are nearly equal to those of the mixture compounded with low density powder while the sound velocities of them have a great difference. When the RTV silicon rubber is compounded with low and high density powders, it is possible to vary the sound velocity of this mixture by choosing the concentrations of low and high density powders without change of specific acoustic impedance.
  • 近野 正, 尾山 茂, 富川 義朗, 菅原 澄夫
    原稿種別: 本文
    1979 年 35 巻 1 号 p. 36-42
    発行日: 1979/01/01
    公開日: 2017/06/02
    ジャーナル フリー
  • 鈴木 淳一, 小寺 一興
    原稿種別: 本文
    1979 年 35 巻 1 号 p. 43-47
    発行日: 1979/01/01
    公開日: 2017/06/02
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  • 高木 堅志郎
    原稿種別: 本文
    1979 年 35 巻 1 号 p. 48-49
    発行日: 1979/01/01
    公開日: 2017/06/02
    ジャーナル フリー
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