• 산업기술연구
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• 제27권B호
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• pp.59-64
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• 2007

This study introduces an environmental noise evaluation procedure and results for a wind turbine (W/T) system. Test and evaluation are required by the international standard IEC 61400-11 in the aspect of environmental effect. Test and evaluation are performed on U-50 WT model which is first developed by the domestic W/T manufacturer. W/T test model is under operation in Daekwanryung wind test site. An integrated monitoring system in the test site is utilized for the evaluation. With the noise signal, meteorological data and W/T operational data are monitored in real time by the integrated monitoring system using LabVIEW. From the measured noise data, acoustic power level are estimated and compared with those of other similar size WT under the wind speeds required by international standard.

• 소음진동
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• 제8권4호
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• pp.706-714
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• 1998

The purpose of this study is to analyse the main factors and attributes of psychological evaluation to noise. For this purpose, a psycho-acustic experiment was conducted by using the method of rating scale. 52 subjects were participated in the experiment, 20 stimuli were presented to subjects in random order with 23 adjectives. As a result of factor analysis, it was found that the primary factors for evaluating the quality of noise subjectively are four factors of unpleasantness, intensity, irregularity, and sharpness. And, as a result of MDPREF(multi-dimensional analysis of preference data), it was found that the noise sources including the factors of unpleasantness, intensity, and irregularity are related to the sounds of hammering in construction field, car horn, road traffic, idling of car, and printing by computer printer, and the factor of sharpness are the sounds of car siren, claps of thunder, car horn, and snowstorm etc.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.790-795
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• 2004

The characteristics of refrigerator noise recorded in anechoic chamber was investigated in condition of a the real living room and a kitchen. To predict the noise propagation in an apartment unit, room acoustic simulation software was used. It was found that the noise level in the real living room was $4\sim8dB$ higher than in the anechoic chamber. When a noise barrier and absorption materials were used on the rear wall and floor, the noise level reduced up to $3\sim4dB$. In addition, when the subjective evaluation of auralized refrigerator noise was undertaken using headphone, it was revealed that 21dB (A) is the allowable sound pressure level of 95% satisfaction.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 추계학술대회논문집
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• pp.311-317
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• 2007

The reduction of the Vehicle interior noise has been the main interest of NVH engineers. The driver's perception on the vehicle noise is affected largely by psychoacoustic characteristic of the noise as well as the SPL. The previous methods to evaluation of the SQ about vehicle interior noise are linear regression analysis of subjective SQ metrics by statistics and the estimation of the subjective SQ values by neural network. But these are so depended on jury test very much that they result in many difficulties. So, to reduce jury test weight, we suggested a new method using Mahalanobis distance for SQ evaluation. And, optimal characteristic values influenced on the result of the SQ evaluation were derived by signal to noise ratio(SN ratio) of the Taguchi method. Finally, the new method to evaluate SQ is constructed using Mahalanobis-Taguchi system(MTS). Furthermore, the MTS method for SQ evaluation was compared by the result of SQ grade table at the previous study and their virtues and faults introduced.

• 한국소음진동공학회논문집
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• 제18권4호
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• pp.393-399
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• 2008

The reduction of the Vehicle interior noise has been the main interest of NVH engineers. The driver's perception on the vehicle noise is affected largely by psychoacoustic characteristic of the noise as well as the SPL. The previous methods to evaluation of the SQ about vehicle interior noise are linear regression analysis of subjective SQ metrics by statistics and the estimation of the subjective SQ values by neural network. But these are so depended on jury test very much that they result in many difficulties. So, to reduce jury test weight, we suggested a new method using Mahalanobis distance for SQ evaluation. And, optimal characteristic values influenced on the result of the SQ evaluation were derived by signal to noise ratio(SN ratio) of the Taguchi method. Finally, the new method to evaluate SQ is constructed using Mahalanobis-Taguchi system(MTS). Furthermore, the MTS method for SQ evaluation was compared by the result of SQ grade table at the previous study and their virtues and faults introduced.

• 대한환경공학회지
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• 제33권10호
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• pp.748-755
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• 2011

1960년대 산업화 이후 기계화가 가속되어 산업발달에 많은 기여를 하였으나 고소음 작업장에서 발생하는 소음피해에 대한 대책은 거의 없는 실정이다. 특히 공장 및 작업장에서 발생하는 기계소음은 반복적으로 되풀이되어 충격적이며, 강한 소음으로 대부분의 현장 작업자들은 높은 불쾌감과 청력장애의 위험을 부담하고 있다. 이러한 관점에서 이 연구는 고소음 작업장에서 발생하는 작업기계 소음을 평가하기 위한 적정 평가어휘를 추출하고자 했으며, 이렇게 추출된 어휘는 작업 기계소음을 평가하기 위한 음향심리 실험 및 기계소음 규제기준 설정을 위한 유용한 자료로 활용될 수 있을 것으로 사료된다.

• 한국소음진동공학회논문집
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• 제18권6호
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• pp.663-673
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• 2008

The purpose of this study is to analyze the appropriate evaluation method for the water supply and drain noise of bathroom in apartment and to propose some fundamental idea on its regulation. For this reason, it was studied the acoustical characteristics of water supply and drain noise as modifying the water supply pressure for the washbasins and toilet stools and suggested the optimum evaluation method through psychoacoustic test. As a result of investigation of the levels by evaluating the adjectives and noise sources with 7-step criteria corresponding to each level of plumbing noises and analysis of the correlation between physical evaluation values by comparing the criteria, dB(A), N, and NC, with subject's response, determination coefficient($R^2$) was shown to be relatively fair or higher ranged from 0.65 to 0.92. It is shown that 'Harsh', 'Nervous', 'Unpleasant', 'Distasteful', and 'Repellent' as a second factor are to be appropriate to evaluate plumbing noise. Above these results could be used in basic data establishing KS(Korean Standard) for evaluation and rating procedure and measures reducing these noise.

• 한국소음진동공학회논문집
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• 제20권11호
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• pp.1001-1008
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• 2010

The architectural, facility makes the housing environment more pleasant, while too much noise coming from machinery room is detrimental to the workers physically and mentally. Therefore, more sound insulation and sound proof policies are increasingly required. However, as the annoyance caused by facility noise is influenced by various human listening characteristics as well as physical characteristics such as sound pressure level, it requires subjective evaluation characteristics through acoustic-psychological approach. For this purpose, the facility noise in the machinery room was actually measured and analyzed in the field to understand physical characteristics, and the correlation between physical evaluation value and psychological response value through listening test. Further, this study aims at presenting the data to set the standards of 'Just noticeable difference' of the facility noise together with reasonable evaluation with psychological reaction, through the grading of facility noise using trend formula. In the result, 13 stages of physical properties were forecasted for each evaluation method, together with 'Just noticeable difference' using the grading of architectural facility noise.

• 한국안전학회지
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• 제26권4호
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• pp.20-26
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• 2011

This paper is to investigate noise source for reciprocating type air compressors. The reciprocating type air compressors are widely used in the small and medium sized enterprise and many employees are affected and irritated by their noise during working. The investigation and analysis of the noise source were made according to the ISO 1680/1 and MIL-STD 7410-1 and noise evaluation of each part of compressors was made. Noise emitted from the intake and exhaust valve and the air receiver tank were dominant compared with those from other parts of compressor. Noise from the motor and the revolution of crank mechanism was negligible relatively with the noise sources as mentioned above.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.730-733
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• 2006

This study aims to offer psychological stability and pleasure by reducing noise perception using appropriate visual information which fit to the situation and useful data for the soundscape design. The results can be summarized as follows; 1) In the Loudness evaluation of the visual information with green colored scenary showed lower evaluation rather than the other colors. 2) With the Green and Blue colored scenary with road traffic and shopping street alongside the road, lower perception of road traffic noise was showed. 3) With the White and Red scenary higher evaluation was showed than the original sound, but with the Green colored scenary lower evaluation was showed than the standard sound.