• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2005.11a
• /
• pp.443-448
• /
• 2005

This study aimed to evaluate the room acoustical performances of multi-purpose halls, analyzing the architectural features by survey and the acoustical characteristics by measurements. Moreover, vocabularies appropriate for the evaluation of the room acoustical performance were determined through questionnaire and subjective responses. From the correlation analysis and factor analysis to the physical values through measurements and the subjective evaluation using vocabularies, useful vocabularies for the evaluation of multi-purpose halls' acoustical performances were determined and physical parameters corresponding to the vocabulary were identified.

• Proceedings of the Acoustical Society of Korea Conference
• /
• 1998.06e
• /
• pp.242-427
• /
• 1998

• The Journal of the Acoustical Society of Korea
• /
• v.10 no.5
• /
• pp.5-10
• /
• 1991

본 연구에서는 알루미늄 금속의 결합 검출을 위한 meander line 형 EMAT를 모의 실험을 통해 설계하고 그 대역특성을 연구분석 하였다.

• The Journal of the Acoustical Society of Korea
• /
• v.13 no.2
• /
• pp.96-103
• /
• 1994

• The Journal of the Acoustical Society of Korea
• /
• v.24 no.2
• /
• pp.111-116
• /
• 2005

This study deals with a subjective assessment to investigate the preferred acoustic conditions and determine the important acoustical parameters in concert halls. A subjective test was carried out using dummy head recorded sounds made in actual halls in Australia (referred to as Hall A and Hall B) to evaluate the acoustic performance of two halls. The results of subjective tests were then correlated with measured acoustical parameters to investigate the significant determinants for the preference judgements. The listeners show a stronger Preference for seats in the Hall B than those in the Hall A. The low preferences for seats in the Hall A are in agreement with live performance ratings assessed by musicians. It is found that the sound level is the most significant acoustical parameter for evaluating the overall acoustic preference in the two halls.

• Phonetics and Speech Sciences
• /
• v.6 no.3
• /
• pp.131-138
• /
• 2014

A close-copy stylization of intonation curve was used for an acoustical analysis of emotional speech. For the analysis, 408 utterances of five emotions (happiness, anger, fear, neutral and sadness) were processed to extract acoustical feature values. The results show that certain pitch point features (pitch point movement time and pitch point distance within a sentence) and sentence level features (pitch range of a final pitch point, pitch range of a sentence and pitch slope of a sentence) are affected by emotions. Pitch point movement time, pitch point distance within a sentence and pitch slope of a sentence show no significant difference between male and female participants. The emotions with high arousal (happiness and anger) are consistently distinguished from the emotion with low arousal (sadness) in terms of these acoustical features. Emotions with higher arousal show steeper pitch slope of a sentence. They have steeper pitch slope at the end of a sentence. They also show wider pitch range of a sentence. The acoustical analysis in this study implies the possibility that the measurement of these acoustical features can be used to cluster and identify emotions of speech.

• Proceedings of the Acoustical Society of Korea Conference
• /
• spring
• /
• pp.319-325
• /
• 1999

• Proceedings of the Acoustical Society of Korea Conference
• /
• autumn
• /
• pp.161-164
• /
• 2000

음향공간의 질은 그 공간을 사용하는 사용자의 주관적인 판단에 의해 최종적으로 평가된다. 그러나 이와 같은 주관적인 판단은 주어진 공간에 대한 사용자의 종합적인 지각과 경험을 토대로 하여 이루어지는 것이므로 이를 정량 화하여 상호 비교하는 작업의 어려움과 한계는 많은 연구논문을 통해 지적된 바 있다 본 연구는 음향공간 내에서 음색지각의 변화를 JND개념을 이용하여 정량화하고 이를 음향선호도와 비교함으로써 기존의 주관적 평가방법보다 객관화된 평가방법 제안의 가능성을 논하고자 한다.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
• /
• 2002.05a
• /
• pp.156-161
• /
• 2002

Results of theoretical investigations on acoustical properties of hydrodynamic proceeding bearings are presented. Nonlinear analysis of rotor bearing system including rotor imbalance is performed in order to obtain acoustical properties of hydrodynamic proceeding bearings. Furthermore, a cavitation algorithm, implementing the Jakobsson-Floberg-Olsson boundary condition, is adopted to predict cavitation regions in a fluid film. Acoustical properties of hydrodynamic proceeding bearings are identified through frequency analysis of pressure fluctuation calculated from the nonlinear transient analysis. The results show that the acoustical frequency spectra of hydrodynamic proceeding bearings are pure tone spectra, containing the frequency of the shaft rotation and its super-harmonics. The analysis also shows that the super-harmonics are predominant at neighborhood of the fluid film reformation and rupture regions.

• Journal of KSNVE
• /
• v.9 no.1
• /
• pp.131-140
• /
• 1999

A method to reconstruct the sound field around a Korean bell is developed. The sound radiation problem is formulated based on the boundary element method by using the algorithm of the acoustical holography. Sound pressures at the hologram surface are measured and used as input data for the analysis program that was developed in this study. An error minimization scheme is presented to overcome difficulties that arise in the backward reconstruction of the BEM-based acoustical holography In the model fictitious source surfaces were also introduced to reduce the complexity stemmed from the source shape. The sound field associated with the (4.0) vibrational mode of the Korean bell was visualized and verified experimentally.