• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 추계학술대회 논문집
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• pp.819-820
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• 2011

• 한국소음진동공학회논문집
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• 제22권3호
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• pp.234-243
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• 2012

In this paper, a sound quality indices for the evaluation of vehicle intake and exhaust noise were developed through a correlation analysis of objective measurement data and subjective evaluation data. At first, intake and exhaust orifice noise were measured at the wide-open throttle sweep condition. And then, acoustic transfer function between intake orifice noise and interior noise at the steady state condition was measured. Also, acoustic transfer function for exhaust system was measured as the same method. Simultaneously, subjective evaluation was carried out by the paired comparison and semantic differential method by 27 engineers. Next, the correlation analysis between the psycho-acoustic parameters derived from the measured data and the subjective evaluation was performed. The most critical factor was determined and the corresponding sound quality index for the intake and exhaust noise was obtained from the multiple factor regression method. At last, the effectiveness of the proposed index was investigated.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.814-819
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• 2004

When we evaluate sound, there are various methods for noise such as A-weighted SPL(sound pressure level), NC(noise criteria), NR(noise rating) and SIL(speech interference level) etc. however, it is not sufficient for the sounds supplied to public places used in soundscape design. Consequently it is needed to develop the tool for evaluating the good acoustical environment and futhermore quantifying the effect of improvement by supplying sound sources. In this study, it was tried to analyse the sound sources applied for soundscape design using sound quality parameters. The sound sources used were natural sound artificial sound. For the sound quality parameters, Loudness(L), Sharpness(S), Fluctuation strength(FL), Tonality(T), Roughness(R), Unbiased Annoyance(UA) were used and sound quality values were compared both natural and artificial sounds, depending on the convolution of sound sources with background noise, the duration, the frequency contents and the SPL. As a result, the values of L and UA have shown to be changed comparing to the other parameters, and it is necessary to analyse the correlation with subjects' responses.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 춘계학술대회논문집
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• pp.595-598
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• 2005

The impact sound of the golf club is one of the major factors to purchase it. Sound qualify evaluation techniques are mostly developed for harmonic sounds. Sound quality metrics for the impact sound is proposed in this study. Jury test, one of the typical subjective evaluation scheme, is carried out for evaluating the sound quality of 11 different golf drivers. Above subjective classification results are assumed to be the right answers. Conventional objective evaluation methods such as Zwicker loudness sensory pleasantness are calculated. Wavelet analysis and instantaneous loudness are applied in order to evaluate the transient sounds, which shows better correlation with the results from those by jury test.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 춘계학술대회논문집
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• pp.529-534
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• 2005

This study performed an physical analysis on the characteristics of urban environmental sound divided into three parts depending on their features. Object sounds were classified into traffic sound, waster sound and spatial sound. Traffice sound was selected because it is dominant sound in urban environment, and water sound is selected because it generally supplies pleasantness in contrast to traffic sound, Finally spatial sound was considered because it represents sound in various places of city having lots of behaviors and types of sound due to them. Physcal analysis was carried out using sound quality indices based on Zwicker's loudness, $L_{Aeq}$(equivalent noise level), Ln(percentile noise level) and other acoutical attributes applied to previous study. Through the analysis, this study aims to compare the acoustical characteristics of urban environmental sound and to provide fundamental data for the evaluation of urban environmental sound.

• 감성과학
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• 제1권1호
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• pp.171-179
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• 1998

스피커의 음질을 평가하기 위해서 가장 많이 측정하는 것은 주파수 응답이다. 그러나 주파수 응답으로부터 바로 스피커의 성능을 평가하기는 어려운데, 이는 인간의 청각특성이 주파수나 음압에 대해 선형적인 관계를 가지지 않기 때문이다. 본 논문에서는 인간의 청각특성 중 24개의 임계대역과 라우드니스 등을 이용하여 스피커의 성능을 평가하는 방법을 제안한다. 본 논문에서 제안하는 방법은 지향서을 고려하여 스피커의 주파수 응답을 구한 후 이를 이상적인 스피커의 주파수 응답과 임계대역-라우드니스 영역에서 비교하여 음질평가지수를 산출한다. 제안된 방법에 의한 스피커의 성능 평가법은 신뢰도가 가장 큰 문제가 되므로 청취평가를 수행하여 그 결과와 비교하고 상관관계를 보였다. 제안된 방법에 의한 결과와 청취평가의 결과는 0.9765의 높은 상관관계를 가졌는데, 이는 본 논문에서 제안하는 방법이 청취평가 대용으로 훌륭히 사용될 수 있음을 의미한다.

• 드라이브 ㆍ 컨트롤
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• 제13권2호
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• pp.19-25
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• 2016

Recently, drivers have begun to regard comfort in the cabin as one of the most important factors in construction equipment like forklifts. Accordingly, it has become more important to design a forklift cabin with a better sound quality as well as lower sound level, which can make a driver more comfortable. In this paper, the correlation between subjective evaluation and Zwicker's sound quality index was analyzed through a blind test by a few workers in forklifts and other construction equipment in several countries. Correlation analysis showed that Loudness and Sharpness were ranked in sequence, and tendencies were different from country to country. Also, contribution analysis for Loudness and Sharpness using operational transfer path analysis (OTPA), which is widely used in the field of noise, vibration, and harshness (NVH), was performed. However, Loudness and Sharpness cannot be used with OTPA directly because there are no linear relationships between the sources and receivers. In this paper, both are calculated by applying the DIN 45631 method with a contribution rate (%) of 1/3 Octave Sound Pressure Level by OTPA method in addition to considering spectral masking.

• 한국소음진동공학회논문집
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• 제15권8호
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• pp.945-953
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• 2005

The purpose of this paper is to develop a linear regression model for the sound quality index of vehicle Interior noise. For this, objective measurement data of the vehicles driving in acceleration was measured. On the basis of analysis, psychoacoustic parameters were extracted and subjective evaluation was performed by noise and vibration expert evaluators. For the subjective evaluation, the paired comparisons and the semantic differential methods were used to evaluate sound quality of vehicle interior noise. By the paired comparison which evaluate two pairs of vehicle interior noise, the preference was estimated. With the semantic differential and the factor analysis, it was evaluated words of two pairs which expressed appropriately the sense of evaluator about noise source. Therefore the characteristics of the sound qualify for the vehicle were differentiated. From the results of both the correlation analysis and the multiple factor regression analysis, the sound quality evaluation model for the sense of human hearing was derived and indexed.

• 한국소음진동공학회논문집
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• 제21권10호
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• pp.883-889
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• 2011

The brand sound of vehicle diesel engine is recently one of the important advantage strategies in the automotive company. Because various noise components masked under high frequency level can be audible in quieter driving situation. Many researches have been carried out for subjective and objective assessments on vehicle sounds and noises. In particular, the interior sound quality has been one of research fields that can give high quality feature to vehicle products. Vehicle interior noise above 500 Hz is usually controlled by sound package parts. The materials and geometries of sound package parts directly affect on this high frequency noise. This paper describes the sound quality evaluation method for the vehicle diesel engine noise to establish objective criteria for sound quality assessment. Considering the sensitivity of human hearing to impulsive sounds such as diesel noise, the human auditory mechanism was simulated by introducing temporal masking in the time domain. Furthermore, each of the human auditory organs was simulated by computer codes, providing reasonable analytical explanations of typical human hearing responses to diesel noise. This method finally provides the sound quality index of vehicle diesel engine noise that includes high frequency intermittent offensive sounds caused by impacting excitations of combustion and piston slap.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.1459-1464
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• 2006

In the previous studies on railway noise analysis, the main purpose of noise analysis is concerned with the reduction of A-weighted sound pressure level in order to satisfy noise regulations. However, more important facts on noise reduction are the subjective feelings of the human being on noise because people might be annoyed from the noise caused by train. In this paper, railway noise from different type of train are compared using the calculation of sound quality metrics with using strength related method that is calculation of A-weighted sound pressure level.