Contents: Mean sound spectra of standard colloquial Chinese vowels; Pitch indicator and pitch characteristics of standard colloquial Chinese tones; Effects of weak background sound on sound signal perception; Relation of monophthong identification rate to syllable duration; Normal-mode sound field in a negative-gradient shallow sea; Ultrasonic spot welding (review); Notes on research and techniques measurements of sound speeds in human and animal tissues; High-frequency anechoic water tank; Characteristics of muffler testing equipment; Sound quality of a large auditorium; and Scientific activities.

The directional distribution of sound field and its measurement, and on the surface waves generated by a vibrating side wall.

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