This paper is a further presentation and discussion of the author's voice research and previous paper and film on singer's (high) formant associated with different larynx position in styles of singing. The main results and points are: 1. The singer's high formant pattern varies with similar characteristic (two to four high and often compact energy peaks, including a possible extra peak f_e, in the bright frequency range); 2. The f_e is also found in high laryngeal singing and does not necessarily appear as a typical acoustic feature in all professional singing voice; 3. Sundberg's lowered larynx interpretation does not explain the extra formant, singer's formant, and voice quality; 4. Sundberg's different definitions of singer's formant are not inclusive of the various formant patterns of singing associated with different laryngeal position and different types ; 5. The author also suggests a definition for the singer's formant; 6. The low laryngeal position could be yet regarded as a distinctive feature for the covered singing voice though not for the trained singing voice; 7. The source characteristics and the interaction between the source and the supra/sub glottal systems are possibly different in styles of singing associated with various laryngeal positions.

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Experiments on the individual and combined effects of noise and vibration of moderate intensity were conducted with choice reaction time (CRT) task and paired associates learning (PAL) task. The experiments related to continuous noise (64 and 74 dB (A)), intermittent noise (74 dB (A), peak az) and continuous vibration (vertical whole-body sinusoidal in 5 Hz at 76 dB (re 10^-5 m/s²)). Deterioration of performance in CRT were observed in all conditions of noise alone and vibration as compared with the control (43 dB (A) ambient noise and no vibration). As regards PAL, continuous noise produced promotion of performance, but intermittent noise and vibration alone led to deterioration of performance. The noise combined with vibration demonstrated three types of effects.

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This paper describes the experiments on recognition of stop consonants in continuous speech by use of local spectral peaks. The spectrum obtained through a band pass filter bank is sampled every 10 ms. The sampled spectrum is represented by a binary valued vector in which every element denotes the presence or absence of a local peak. The frequency distribution of local spectral peaks in 40 ms from the burst frame is transformed into the feature vector. And the conditional probability of the feature vector is used for the recognition. The experiments were carried out using 212 Japanese words uttered by 10 males and 10 females. The stop consonants are discriminated at a comparatively high rate using only the local spectral peaks. To improve the recognition rates, the differences between successive spectra are used. The recognition rates for the unvoiced stops for the 10 male and 10 female speakers are 82.6% and 79.1 % respectively, by the leaving-one-out experiments ; those for the voiced stops are 74.5 % and 66.1 %. It turns out that the local spectral peaks and the temporal changes in the spectra are very significant features for discriminating stop consonants.

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In the practical engineering field of noise control, it is as important as the sound source countermeasure to improve the sound propagation characteristics by newly setting a sound insulation system. On the other hand, the noise statistics like an L_x (x=5, 10, 50, 90, ) defined as a (100 -x) percentage point of the sound level distribution are very important as well as the lower order energy moment statistics like an L_eq in the actual noise evaluation and regulation problems. In this paper, two kinds of probabilistic evaluation methods for sound insulation systems are theoretically proposed from typically different points of view for the probability distribution of the transmitted sound intensity, when a general stationary random noise having an arbitrary distributionform and frequency characteristics is insulated by a wall. To evaluate its sound transmission coefficient, a somewhat modified statistical energy analysis method has been used.The validity of the theoretical results is experimentally confirmed by applying it to the actually observed data on the output response fluctuation of single and double walls type insulation systems inserted between two reverberation rooms.

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This paper describes a vibration based diagnostic method for estimating the surface roughness on the race in ball bearings. The surface roughness has been measured bya stylus which directly traverses the surface of the ring obtained by taking apart the ball bearing. We developed a new method to accurately estimate the surface roughness by analyzing the short-length vibration signal which is excited when balls contact with the surface of a defective rotating ring in a ball bearing. Our experimental results confirm that the roughness estimated by the proposed method agrees with that measured directly by using a stylus even in the case of crack jam wide. We applied this new method to the diagnosis of surface roughness in small-sized ball bearings and inferior samples were detected with a 94.7 % accuracy rate.

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