• 말소리와 음성과학
• /
• 제4권3호
• /
• pp.13-23
• /
• 2012

The sound /w/ has been traditionally regarded as an independent segment in Korean regardless of the phonological contexts in which it occurs. There have been, however, some questions regarding whether it is an independent phoneme in /CwV/ context (cf. Kang 2006). The present pilot study examined how Korean /w/ is realized in $/S^*wV/$ context by performing some perception tests. Our assumption was that if Korean /w/ is a part of the preceding complex consonant like $/C^w/$, it should be more or less uniformly articulated and perceived as such. If /w/ is an independent segment, it will be realized with speaker variability. Experiments I and II examined the identification rates as "labialized" of the spliced original stimuli of $/S^*-V/$ and $/S^{w*}-^wV/$, and the cross-spliced stimuli $/S^{w*}-V/$ and $/S^*-^wV/$. The results showed that round qualities of /w/ are perceived at significantly different temporal point with speaker and context variability. We therefore conclude that /w/ in $/S^*wV/$ context is an independent segment, not a part of the preceding segment. Full-scale examination of the production test in the future should be performed to verify the conclusion we suggested in this paper.

• 한국소음진동공학회논문집
• /
• 제16권7호
• /
• pp.683-689
• /
• 2006

The sound absorption materials have been used to enhance the performance of a noise barrier and improve the room acoustics. In this study, 6 products of sound absorption materials generally used in Korea were chosen, and their absorption performance was tested in various conditions, that is, it was measured while changing thickness, density and air-gap in their back, and measured with or without facing on their face.

• 한국생산제조학회지
• /
• 제9권6호
• /
• pp.9-18
• /
• 2000

This study includes noise automatic inspection system for washing machine auto-transmission one of modern home necessary. We effort to find and certificate sound noise source by sound power and sound intensity, and apply to frequency analysis in vibration related sound noise. still more we have been studying to data acquisition and programming for MS VisualBasic version 5.0. System component is below. 1) Pentium PC or data acquisition. 2) DSO for noise acquisition. 3)S/W for comparison and decision. 4) I/F Board for data communication. Wave form data through the DSO are converting to ASCII code data. The ASCII code through binary converting S/W. Finally we will making noise monitoring system and automatic inspection system.

• KIEAE Journal
• /
• 제8권5호
• /
• pp.3-10
• /
• 2008

The Korean traditional architecture has developed by adapting to the natural environment, and has successfully created a comfortable indoor settings by using the surrounding natural resources. This is reflected in the building layout, space design and even materials. Our traditional wooden windows adjusting ambient temperature and humidity have both the functions of window and door, although they are clearly divided in the West. The opening and closing method of our traditional windows is similar and their dimensions are shown not to be standardized but diverse in terms of the characteristic of wooden furniture and that of components placed between columns. Thus this study aims to research the sound insulation and absorption performance of traditional windows to be varied with thickness, finishing method of window paper and thickness of air layer. Despite increase of the thickness of window paper, sound absorption was reduced, and the same result was shown when both sides of the structure were finished with thick window paper. The sound insulation performance of the windows could be evaluated to be inappropriate with $R_w$ 0 ~ $R_w$ 14.

• Interaction and multiscale mechanics
• /
• 제3권4호
• /
• pp.373-387
• /
• 2010

This study is intended to assess low frequency sound radiated from a viaduct under normal traffic. The bridge comprises steel box girders and wide cantilever decks on which vehicles pass. The low frequency sound and the acceleration response of the bridge under normal traffic are measured to investigate how bridge vibrations affect the low frequency sound observed near the bridge. Observations demonstrate that strong relationships exist between frequency characteristic of bridge's acceleration response and the sound pressure level of low frequency sound. A noteworthy point is that the dynamic feature of the sound pressure level is mostly affected by dynamic feature of the span locating near the observation point.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2008년도 추계학술대회논문집
• /
• pp.112-120
• /
• 2008

Today, the use of a vacuum cleaner gave us the higher quality of life than past time, but sometimes made us w1comfortable in the house because of the specific noise that is annoying. So we need to study how sound absorbtion materials affect sound power level and sound quality with sound metrics. In this paper, we will measure and calculate sound power level for vacuum cleaner and analyze characteristics of the noise for 10 Signals according to materials positioned in vacuum cleaner. The multiple regression analysis can estimate the nonlinear characteristics of relation between subjective evaluation and sound metrics. So we will develop sound quality index for vacuum sound.

• Journal of Oral Medicine and Pain
• /
• 제24권4호
• /
• pp.397-410
• /
• 1999

In order to obtain the basic data concerning the optimal parameters in using Nd:YAG laser as a therapeutic modality to dentinal hypersensitivity, the author prepared 3 sections of sound dentin and 10 sections of sclerotic dentin with thickness of $0.5mm{\pm}0.1mm$ from human extracted teeth of anteriors and premolars, and applied the laser energy from a fiberoptic delivered, free running, pulsed Nd:YAG laser (wavelength 1064nm, pulse duration $120{\mu}sec$, fiber diameter $320{\mu}m$) to surfaces of sound and sclerotic dentin sections for 1 second with contact/unidirectional moving mode of the fiber under speed of 3mm~4mm/sec and parameters of 0.5W/10Hz, 1.0W/10Hz, 1.5W/10Hz, 2.0W/10Hz: $62J/cm^2$, $124J/cm^2$, $187J/cm^2$, $249J/cm^2$. The author comparatively evaluated the characteristics of ultrastructural changes on surfaces of sound and sclerotic dentin sections irradiated by the pulsed Nd:YAG laser using the scanning electron microscopy. A fairly ill-defined bordered surface of partially closed and melted dentinal tubules can be seen on the scanning electron microscopic feature of the sound dentin surface irradiated by the pulsed Nd:YAG laser with energy density of $62J/cm^2$. The physical modification of sound dentin surface extensively occurred depended on the increase of energy density from $62J/cm^2$ to $124J/cm^2$, $187J/cm^2$, $249J/cm^2$. While, a fairly well-defined bordered surface of partially closed and melted dentinal tubules with thickened peritubular dentin can be seen on the scanning electron microscopic feature of the sclerotic dentin surface irradiated by the pulsed Nd:YAG laser with energy density of $62J/cm^2$. The physical modification of sclerotic dentin surface of a fairly rough, shallow depression with many cracks, thickened peritubular dentin and structureless dentinal tubules extensively occurred depended on the increase of energy density from $62J/cm^2$ to $124J/cm^2$, $187J/cm^2$, $249J/cm^2$ compared to those of sound dentin surface irradiated by the pulsed Nd:YAG laser under the same parameters. Therefore, it is recommended that the pulsed Nd:YAG laser as a therapeutic modality to dentinal hypersensitivity should be applied with the less energy density than $62J/cm^2$ on the sound dentin surface, and its energy density on the partially sclerotic dentin surface should be lower than that on the sound dentin surface to preserve tooth from unnecessary excessive structural destruction.

• 한국감성과학회:학술대회논문집
• /
• 한국감성과학회 1999년도 춘계학술발표논문집 논문집
• /
• pp.265-269
• /
• 1999

This study was carried out to evaluate human subjective sensation for fabric rustling sounds and predict the sensation with quantified sound color measurements and mechanical properties of fabrics. Thirty subjects at Virginia Tech were asked to evaluate seven sound sensation descriptors by semantic differential scale after hearing eight different fabric sounds. Sound measurements were quantified by calculating total sound pressure(LPT), level range(ΔL), and frequency difference (Δf). Mechanical properties of fabrics were measured by KES-FB. Subjective sensation for fabric sound showed significant differences among fabrics except clearness sensation. Subjective sensation predicted by sound measurements showed well fitted regression equation with ΔL and LPT> Sharpness, clearness, and highness were significantly released with mechanical properties of fabrics. All sensation was found to be predicted with sound measurements L:PT and Δf and mechanical properties such as LT, 2HG5, WC, T, and W.

• 한국소음진동공학회논문집
• /
• 제17권5호
• /
• pp.373-378
• /
• 2007

Today, the use of the sound absorptive material is increasing to improve the room acoustics in the auditorium and music hall, etc. Usually, the sound absorption materials have been used to enhance the performance of a noise barrier and improve the room acoustics in construction site. Generally, the sound absorbtion coefficients are the most important factor reflecting the sound absorbtion performance. There are two methods to measure the sound absorption coefficient. The first one is the reverberation room method, and the second is the impedance tube method. In this study, we measure the sound absorbtion coefficients using these two methods, and then we compared the results of the sound absorbtion coefficients to look into the difference of results between reverberation room method and impedance tube method. Also we compared the results of the sound absorbtion coefficients with respect to the size of sample and the volume of reverberation room. From the experiment, we could see that the sound absorbtion coefficients are measured equally for different sample size. But the sound absorbtion coefficients are measured differently according to test methods and test conditions.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2007년도 춘계학술대회논문집
• /
• pp.710-714
• /
• 2007

The wheat-gluten vendor's Shears Sound which was ever able to hear barely at the conventional market place or some specific gala period is a familiar sound to us, also a delightful sound even without any reason. The blunt Shears Sound spreading faraway attracts the mind of hearer and it makes neighbors gathering. Nevertheless, it becomes to be left as being a forgotten sound little by little to our society that rapidly growing with high degree. In this Study, as for an acoustic analysis of the wheat-gluten Shears Sound, as being a forgotten our own sound, in order to examine the difference according to the character of various shears, after making 26 pieces of various Shears and we had ever measured, appraised on the sound pressure level by each wave-form and frequency of respective Shears Sounds at the semi-anechoic chamber, W University. At the study result, the acoustic character of wheat-gluten vendor's Shears Sound was able to be grasped, and we could find out 4 pieces of Shears which were judged as more superior in acoustic capability than the existing wheat-gluten Shears among the 26 pieces of various Shears.