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Volume 32 , Issue 5
Showing 1-10 articles out of 10 articles from the selected issue
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INVITED REVIEW
  • Sofia Dahl
    Volume 32 (2011) Issue 5 Pages 168-173
    Released: September 01, 2011
    JOURNALS FREE ACCESS
    Like all music performance, percussion playing requires high control over timing and sound properties. Specific to percussionists, however, is the need to adjust the movement to different instruments with varying physical properties and tactile feedback to the player. Furthermore, the well defined note onsets and short interaction times between player and instrument do not allow for much adjustment once a stroke is initiated. The paper surveys research that shows a close relationship between movement and sound production, and how playing conditions such as tempo and the rebound after impact affect the movements. Furthermore, I discuss differences in movement organization, and visual information from striking movements.
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PAPERS
  • Kyawt Yin Win, Tomio Takara
    Volume 32 (2011) Issue 5 Pages 174-181
    Released: September 01, 2011
    JOURNALS FREE ACCESS
    We have introduced a novel Myanmar text to speech (MyanmarTTS) system with rule-based tone synthesis. Myanmar is a tonal language that possesses unique characteristics compared with other tonal languages such as Chinese, Vietnamese and Thai. Such languages have complicated fundamental-frequency (F0) patterns of tones, and F0 is of foremost importance. Myanmar tones are unique in their simplistic pattern related not only to F0 but also, more specifically to duration. Myanmar tones have different durations between short-tone and long-tone groups. In accordance, we defined a tone rule employing two parameters F0 at the center of the syllable and the syllable’s duration. The rule is implemented with a linear F0 pattern. Large variability exists in the F0 and duration uttered by different speakers of different syllables. Hence, for tone synthesis, normalization of the F0 and duration is important and necessary to discriminate tones. We proposed a normalization method and the effectiveness of this method was confirmed in the distribution of the F0 and duration. The intelligibility of the synthesized tone was confirmed through listening tests with correct rates of 95.6% for male and 97.8% for female speech. As a result, we showed that the linear pattern is sufficient for Myanmar tone synthesis.
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  • Takumi Asakura, Shinichi Sakamoto
    Volume 32 (2011) Issue 5 Pages 182-193
    Released: September 01, 2011
    JOURNALS FREE ACCESS
    The sound insulation performance of such wall systems as window sashes, doors, and movable partition walls is often affected by sound waves propagating through narrow gaps that exist at their peripheral parts. In this paper, the leak transmission characteristics through narrow gaps existing in the window sash was investigated through numerical and experimental studies. First, the validity of the finite-difference time-domain (FDTD) method with nonuniform-mesh system was confirmed through 1-dimensional and 2-dimensional numerical studies. Second, narrow gaps at the peripheral parts of a window sash were numerically modeled and their leak transmission characteristics were calculated by the 3-dimensional FDTD method. To evaluate the calculation results, they were compared with measurement results of leak transmission characteristics of a real window sash. As a result, numerical results showed good agreement with the experimental results.
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  • Motoki Yairi, Kimihiro Sakagami, Kenichi Takebayashi, Masayuki Morimot ...
    Volume 32 (2011) Issue 5 Pages 194-200
    Released: September 01, 2011
    JOURNALS FREE ACCESS
    A microperforated panel (MPP) absorber is known to be one of the most promising alternatives of the next-generation sound absorbers. However, its absorption frequency range is limited to around two octaves because its absorption solely depends on the Helmholtz resonance mechanism. Therefore, the authors have proposed a combination of two different MPP absorbers in parallel, and revealed its potential for achieving a broader absorption frequency range in terms of excess attenuation. In this study, by the hybrid method of BEM and a mode expansion method, the authors investigate the relationship between the excess attenuation caused by the impedance discontinuity at the boundary of the two different MPPs and the sound absorption coefficient derived using the electro acoustical equivalent circuit model. Measurements of the normal incidence absorption coefficients are carried out to validate the equivalent circuit model, and in the experiments, the configuration of the cavity to realize the parallel arrangements for achieving wideband sound absorption is also discussed referring to the experimental results.
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TECHNICAL REPORTS
  • Takahiro Fukumori, Takanobu Nishiura, Masato Nakayama, Yuki Denda, Nor ...
    Volume 32 (2011) Issue 5 Pages 201-210
    Released: September 01, 2011
    JOURNALS FREE ACCESS
    We have been distributing a new collection of databases and evaluation tools called CENSREC-4, which is a framework for evaluating distant-talking speech in reverberant environments. The data contained in CENSREC-4 are connected digit utterances as in CENSREC-1. Two subsets are included in the data: “basic data sets” and “extra data sets.” The basic data sets are used for evaluating the room impulse response-convolved speech data to simulate the various reverberations. The extra data sets consist of simulated data and corresponding real recorded data. Evaluation tools are presently only provided for the basic data sets and will be delivered to the extra data sets in the future. The task of CENSREC-4 with a basic data set appears simple; however, the results of experiments prove that CENSREC-4 provides a challenging reverberation speech-recognition task, in the sense that a traditional technique to improve recognition and a widely used criterion to represent the difficulty of recognition deliver poor performance. Within this context, this common framework can be an important step toward the future evolution of reverberant speech-recognition methodologies.
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  • Sayed Abas Ali
    Volume 32 (2011) Issue 5 Pages 211-215
    Released: September 01, 2011
    JOURNALS FREE ACCESS
    Every day, approximately half a million workers in the construction sector in Egypt are exposed to excessive noise. Noise is one of the most prevalent physical contaminants in the construction sector. The most negative effects of noise exposure are related to the hearing system and may produce occupational deafness or even permanent deafness. These effects have a very important influence on people’s health and well-being. The goals of this study are to carry out measurements to evaluate construction noise levels, which exceed the permissible level set by Egyptian noise standards and policy to protect the public health of workers, to assess noise exposure, and to develop controls for proposing preventive solutions. The noise levels to which the workers in the construction sector are exposed have been studied. A number of representative measurements have been carried out using a sound level meter and a dosimeter to collect data from workers devoted to different tasks in the construction process. The most important levels and indexes have been analyzed with those data.
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