In this paper, we investigated subjective impressions of air-conditioning sounds in a vehicle by using the psychoacoustic parameters of loudness and sharpness. First, we carried out a subjective evaluation using a rating scale method and investigated the relationships between the psychoacoustic parameters and nine evaluation words, quiet, refreshing, heavy, wide, muddy, violent, dry, warm, and cool, that represent impressions of air-conditioning sounds. As a result, we found that the impressions of ``violent'' and ``quiet'' strongly depended on the loudness, and the impressions of ``heavy,'' ``dry,'' ``warm,'' and ``cool'' strongly depended on the sharpness. Next, we performed a factor analysis. As a result, we found that the air-conditioning sounds can be explained by two factors, a volume factor and a thermal factor, which were strongly correlated with the loudness and sharpness, respectively. This result shows that the feelings of heating and cooling perceived from air-conditioning sounds are related to the sharpness. Therefore, a synergetic effect on the heating and cooling performance can be expected by improving the sharpness of air-conditioning sounds.

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Musical psychologists illustrated musical emotion with various numbers of dimensions ranging from two to eight. Most of them concentrated on classical music. Only a few researchers studied emotion in popular music, but the number of pieces they used was very small. In the present study, perceptual experiments were conducted using large sets of popular pieces. In Experiment 1, ten listeners rated musical emotion for 50 J-POP pieces using 17 SD scales. The results of factor analysis showed that the emotional space was constructed by three factors, ``evaluation,'' ``potency'' and ``activity.'' In Experiment 2, three musicians and eight non-musicians rated musical emotion for 169 popular pieces. The set of pieces included not only J-POP tunes but also Enka and western popular tunes. The listeners also rated the suitability for several listening situations. The results of factor analysis showed that the emotional space for the 169 pieces was spanned by the three factors, ``evaluation,'' ``potency'' and ``activity,'' again. The results of multiple-regression analyses suggested that the listeners like to listen to a ``beautiful'' tune with their lovers and a ``powerful'' and ``active'' tune in a situation where people were around them.

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This paper presents a talker localization method using only a single microphone, where phoneme hidden Markov models (HMMs) of clean speech are introduced to estimate the acoustic transfer function from the user's position. In our previous work, we proposed a Gaussian mixture model (GMM) separation for estimation of the user's position, where the observed speech is separated into the acoustic transfer function and the clean speech GMM. In this paper, we propose an improved method using phoneme HMMs for separation of the acoustic transfer function. This method expresses the speech signal as a network of phoneme HMMs, while our previous method expresses it as a GMM without considering the temporal phonetic changes of the speech signal. The support vector machine (SVM) for classifying the user's position is trained using the separated frame sequences of the acoustic transfer function. Then, for each test data set, the acoustic transfer function is separated, and the position is estimated by discriminating the acoustic transfer function. The effectiveness of this method has been confirmed by talker localization experiments performed in a room environment.

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The Japanese Road Traffic Law states that a vehicle horn should be used only in an emergency or in dangerous locations where a horn sign has been installed. However, drivers frequently use their vehicle horn as a signal when passing each other. Furthermore, pedestrians and cyclists are also honked at by drivers. There may be a negative effect of vehicle horn use on people outside the vehicle. Therefore, a questionnaire survey was carried out to ascertain the current circumstances of vehicle horn use. Respondents were asked about the latest or last-remembered instance of horn use in various situations, both when they were driving and when they were pedestrians. With regard to experiences of being honked at by another driver, the questionnaire included questions concerning place, traffic volume, the aim of horn use, the timing pattern of horn use, and the respondent's psychological reaction when honked at by another driver. It was found that drivers briefly honked their horn to express gratitude, or to gain another's attention, in various places. Long honks such as one long honk or two long honks mostly evoked negative psychological reactions in drivers, such as a feeling that the sound of the horn was startling, noisy, or irritating. Furthermore, pedestrians frequently had negative psychological reactions to horns used to gain their attention or to alert them to danger. More than 40% of nondrivers were displeased with the volume and sound quality of horns.

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In a number of engineering fields, information on the distance to the target is very important. We previously proposed an acoustic distance measurement method based on interference between the transmitted and reflected waves, which can be used for distance measurement over a short range. The previously proposed method requires equipment such as a loudspeaker and a microphone for cancellation processing of background components due to the spectrum of the transmitted wave and the transfer function of the measurement system in real environments. Therefore, in the previously proposed method, a sound source of the transmitted wave must be known in advance. In the present paper, we propose a new acoustic distance measurement method based on phase interference obtained using the cross-spectral method with stereo microphones, which does not require the condition that a sound source of the transmitted wave is known. The conventional cross-spectral method requires a measuring remote microphone and a reference microphone to be placed near a loudspeaker, meanwhile the proposed method requires stereo microphones to be placed near a sound source. Finally, we confirmed the validity and effectiveness of the newly proposed method through computer simulations and evaluation experiments in real environments.

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