• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.20 no.10
• /
• pp.983-990
• /
• 2010

Reduction of acoustic loads of space launch vehicles can be achieved by acoustic absorbers satisfying strict cleanness requirements. This limited the use of general porous materials and requires non-porous sound absorbers. Micro-perforated panel absorbers(MPPA) is one of promising sound absorbers satisfying the cleanness requirement for launch vehicles. However, its applicability was limited to low sound pressure levels according to the acoustic impedance model of micro-perforated panels. In this paper the applicability of micro-perforated panel absorbers at high incident sound pressure was investigated in experimental ways. The absorption characteristics of a micro-perforated panel absorber was simulated according to its design variables, e.g., minute hole diameters and aperture ratios. It was shown that optimal design can be readily done by using proposed design charts. Experiments were conducted to measure acoustic properties of the designed micro-perforated panel absorbers. The results showed that acoustic resistance increases rapidly as incident sound pressure level does but change of acoustic reactance can be neglected in a practical point of view. This caused the decrease of peak value of absorption coefficient at high incident sound pressure level, but the amount of reduction can be accepted in practice. The major advantage of the micro-perforated panel absorber(wide absorption bandwidth) was still kept at high sound pressure level.

• The Journal of the Acoustical Society of Korea
• /
• v.25 no.3
• /
• pp.129-136
• /
• 2006

For the environmental noise assessments. A weighted equivalent noise level (LeqA) is used to measure the time varying environmental noise. However, it is not appropriately reflect various environmental noise features and human emotions. The human perception of the noise is affected largely by the psychoacoustic characteristics of noise as well as the sound pressure level In this study, the effective factors of noise qualify are analyzed using the subjective assessment and statistical analysis of environmental noise, such as road traffic noise. construction site noise, noise in daily living. and other. The analysis methodology is composed to three steps as follows : firstly, the values of the sound qualify metrics of various noise sources were analyzed. And to classify the noise sources, we conducted a cluster analysis using sound quality metrics. Secondly, subjective jury testing was carried out using the methods of paired comparisons and semantic differential. Finally, the correlation between the subjective parameters and the noise quality metrics were analyzed. As a result. the human perception characteristics of the various environmental noise are described in some physical parameters of the noise qualify metrics.

• IEMEK Journal of Embedded Systems and Applications
• /
• v.6 no.3
• /
• pp.174-182
• /
• 2011

Conventional home audio system (e.g. AV Receiver, CD Player etc) has a various functionality of audio play, channel mixing, but the remote controller of these audio players is too complex, difficult for user to manage them effectively. Users want to use these functionalities with more easy, comprehensible way. In this study, "intelligent real-sound presentation technology" that support high quality, realistic audio and the "design of complex information and controller of real sound using intelligent real sound play and control interface" will be introduced. So user can actively, realistically enjoy and play real sound based on user's preference, emotion and circumstance, instead of user's passive service.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 1998.04a
• /
• pp.561-567
• /
• 1998

Recently, TV makers have tried for high sound quality and power, However, due to the high power of the speaker the structure of set brings about a sound vibration problem. Therefore, this paper illustrates the sound vibration phenomenon for a monotype TV set and suggests guide lines for reducing the sound vibration in the design of TV sets,

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2014.10a
• /
• pp.481-482
• /
• 2014

• The Journal of the Korea Contents Association
• /
• v.14 no.11
• /
• pp.50-59
• /
• 2014

A basic role of sound is to give realism to the expressions on the screen or to highlight the images using exaggerated effect as a supporting role. In that way, sound effect makes it possible for audiences to naturally understand realistic images. However, the sound effect in movies is not real 'sound' in fact. Rather, sound effect is a separate cinematic tool that needs a separate direction to manipulate sounds in order to create appropriate effects for particular intention in the movie. While watching the movie, the audiences go through unique experience where they comprehend the manipulated world as the real world. Therefore, direction for sound effect must help deliver realism to the images by auditory factors. Thus, effective sound direction shall have precise and independent design for identification, reason and eurythmical match with the screen and occurred sounds shall be designed based on the subjective listening point to see who is actually listening.

• International Journal of Advanced Culture Technology
• /
• v.10 no.2
• /
• pp.269-280
• /
• 2022

It has been common since ancient times to use fashion accessories to make a positive impression on others and develop personal brands. For this manuscript, I've designed a range of personalized electronic sounds and perfume accessories that use personalized scents and sounds to create memorable experiences. These have built-in auditory and olfactory actuators that can generate unique sound and fragrance signatures from the wearer and the other party. Based on the design explorations, I also discussed the issues of design and implementation of personalized electronic sound and fragrance accessories, as well as issues and additional business opportunities for the use of these personalized electronic sound and odor accessories in everyday life.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2008.04a
• /
• pp.33-41
• /
• 2008

Architectural acoustics design of Namsadang exclusive use theaters should be designed to utilize variously to performance space that can fill flavor and taste of Namsadang performance of the Namsadang six yards. Also, analyze special quality that is sound enemy who follow in sound-absorbing materials fare arrangement of innards that is design material of architectural acoustics laying stress on tradition, use purpose and disappointment size that Namsadang exclusive use theaters seeks on the basis of specific space theme that is experience, disappointment form, seat and passageway Wall and ceiling etc. research and sound and meaning of a character wave motion powerful engineering phenomenon and reduction reverberation loss that is happened from indoor manufacturing thing reduction SCALE model of oval structure research and background of AL composition absorbing material of perforate 25% to heighten acoustic absorptivity of practical use internal organs sound absorption material emir quality sound-absorbing materials insert and layer of air most suitable reverberation time of Namsadang exclusive use theaters that 2.2m volume is $42,218\;m^3$ to become 1.2Sec architectural acoustics design do.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2005.11a
• /
• pp.826-829
• /
• 2005

The State of the art of low noise fan design requires the consideration of optimal sound quality. The influential design parameters of the noise level by the centrifugal fan were selected that based on a preliminary test. The centrifugal fans were designed according from the experiment plan method by specify the selected design parameters. The experiments with the machined mock-up's of centrifugal impellers revealed the major design parameters having impacts upon the indices of sound quality (e.g. loudness, sharpness, roughness and fluctuation strength) at the same performance condition. With a response surface method. the major design parameters selected were analyzed to estimate their contributions upon the sound quality of the centrifugal fan and the optimal values were drawn for the consideration of the sound quality by using each level and its regression equation. In addition, the validity of the regression equations were numerically verified by means of the coefficient of determination. Furthermore, the mechanism of how the centrifugal fans influence the determinants of sound quality was suggested.

• Journal of the Korea Society of Computer and Information
• /
• v.28 no.9
• /
• pp.55-62
• /
• 2023

In this paper, we present a method that utilizes geometry-based sound generation techniques to efficiently handle multiple sound sources, wind turbulence, and temperature-dependent interactions. Recently, a method based on reduced raytracing has been proposed to update the sound position and efficiently calculate sound propagation and diffraction without recursive reflection/refraction of many rays, but this approach only considers the propagation characteristics of sound and does not consider the interaction of multiple sound sources, wind currents, and temperature. These limitations make it difficult to create sound scenes in a variety of virtual environments because they only generate static sounds. In this paper, we propose a method for efficiently constructing a sound map in a situation where multiple sounds are placed, and a method for efficiently controlling the movement of an agent through it. In addition, we propose a method for controlling sound propagation by considering wind currents and temperature. The method proposed in this paper can be utilized in various fields such as metaverse environment design and crowd simulation, as well as games that can improve content immersion based on sound.