• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.296-299
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• 2006

This study is about correlation between WECPNL and other units such as NNI, Leq and Ldn for aircraft noise that ere measured by automatic measuring system networks for grasping the effect of aircraft noise and investigated the aircraft noise level from 2004 to 2005 nearby 10 airports in Korea. It is very important to find the relationship among the various noise units, because exchange between the results of many other nation's study can improve the assessment and mitigation study of the aircraft noise. Correlation between WECPNL and M is better than one between WECPNL and Leq and between WECPNL and Ldn, because WECPNL and NNI are based on the PNL.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.11a
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• pp.229-229
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• 2006

WECPNL(Weighted Equivalent Continuous Perceived Noise Level) which designated currently in Domestic 'The Stanrd Method of Measuring Noise and Vibration' is composed of different factor with WECPNL that published in ICAO. Domestic WECPNL is concerned in application of $L_{MAX}$ measurement. On the other hand, ICAO's WECPNL is based on EPNL that includes factors of the pure tone correction and the duration time. NNI and NEF also are each based on PNL and EPNL. Because a military aircraft noise, especially, has the pure tone of high frequency and the irregular duration, it seems to be undesirable to estimate aircraft noise for using Domestic WECPNL. Therefore, this study was performed to detect a flaw of Korean WECPNL, through comparison of the trend of each other aircraft noise index by using equivalent rawdata.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.604-608
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• 2007

The INM simulation program is used to estimate the condition of the exposed area to the noise near a military airport in Korea. $WECPNL_k$, the evaluation unit of korean airport noise, is different from the ICAO $WECPNL_I$ that is used in the simulation program. Therefore, it is inappropriate to compare these units each other directly. This study presents method of comparison between them by using $LA_{MAX}$. The aircraft events are classified into three classes, as departure, overfly and approach. In result, the measurement and simulation seemed to be similar at departure and approach pattern. However, overfly pattern had higher errors between measurement and simulation. Finally, it is necessary to examine the method to determine flight events and duration for the $WECPNL_k$ application.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.421-424
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• 2007

Currently domestic criteria for the aircraft noise is being adapted WECPNL(weighted equivalent continuous perceived noise level), while internationally preferred method is $L_{dn}$ which is based on from $L_{eq}$ and can also evaluate environmental noise. WECPNL used in domestic as an evaluation metric is only for the aircraft noise. It is, therefore, not adequate for the evaluation of residents' injury, moreover, it is very difficult to measure the aircraft noise by WECPNL due to the complicated calculating procedures as long as automatic measuring system is not used. Accordingly, this study aims to propose alternative evaluation metric for the aircraft noise. To achieve this purpose, WECPNL, $L_{eq}$, $L_{dn}$, other metrics and criteria were compared and analyzed.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.793-795
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• 2007

The present study investigates the effect of the flight path of military aircraft on noise map and its WECPNL distribution. Aircraft noise modeling and simulation are made on a Korean military airport by INM(Integrated Noise Model) 6.2 version, and the flight path of military aircraft is modeled by combining takeoff, overfly, approach and touch-and-go modes. The present INM simulations are conducted for two cases with different overfly modes and show that the change of overfly mode remarkably affects the noise influence region and the WECPNL distribution around the aircraft.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11b
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• pp.703-706
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• 2001

Currently domestic criteria for the aircraft noise is being adapted WECPNL(weighted equivalent continuous perceived noise level), while internationally preferred method is which is originated from $L_{eq}$ and can evaluate even environmental noise. WECPNL used in domestic as a evaluation method is only for the aircraft noise. It is, therefore, not adequate for the evaluation of residents' injury, moreover, it is very difficult to measure the aircraft noise with WECPNL due to the complicated calculating procedures as long as automatic measuring system is not used. Accordingly, this study aims to propose alternative evaluation method for the aircraft noise. To achieve this purpose, the data measured by automatic measuring system were gathered and calculated with three evaluation methods： WECPNL, $L_{eq}$ and $L_{dn}$ and the results calculated from different methods were compared and analyzed.

• Journal of Convergence for Information Technology
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• v.9 no.9
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• pp.141-146
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• 2019

The aircraft noise analysis area in this study is a training airfield where various kinds of aircraft are operated. It is difficult to identify the noise analysis as a real measurement in a training airfield. In order to overcome these practical limitations and to establish appropriate noise countermeasures, a noise map is prepared using the Integrated Noise Model Version 7.0 of the aircraft noise prediction program used by the FAA. The noise of C90GT aircraft was measured while flying the takeoff route, landing route, and long route. We want to identify areas where noise damage is more than 70 WECPNL. No area exceeding the legal standard of 70 WECPNL was found in all routes.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.436-441
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• 2007

This study was carried out to evaluate health effects of aircraft noise using THI(Todai Health Index). The questionnaire survey was conducted around the Gimpo International Airport in Seoul, Korea from 8 August to 9 September. Study subjects, 614 residents, were divided into three groups following to the aircraft noise level: under 75WECPNL(area(1)), $75{\sim}80$WECPNL(area(2)) and $80{\sim}85$WECPNL(area (3)). Twelve scale scores are converted to dichotomous variables based on scale scores of 90 percentile value or 10 percentile value in the control group. Logistic regression analysis taking twelve scores converted as the dependent variables and WECPNL(area), age, gender as the independent variables is conducted. Significant dose-response relationships are found in the scale of MOUT, DEPR, NERV, LIFE, where p denotes significance probability of trend test. Factor analysis was carried out and 2 factors are extracted which may be called "somatic factor" and "mental factor". The dose-response relationship with these factors and noise exposure is not clear. But strangely the odds ratio of mental factor in area 2 is the highest and the annoyance of this area is also higher than other areas.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.12 no.6
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• pp.420-430
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• 2002

Rating scales for environmental noise are varied in their calculation procedure. Among them WECPNL (weighted equivalent continuous perceived noise level) is the rating scale for aircraft noise currently being used in domestic and applied only for aircraft noise. However $L_{dn}$ calculated from $L_{eq}$ $L_{eq}$ is used as a rating scale for not only aircraft noise but also environmental noise. Besides, it is easy to calculate and internationally preferred. It is, therefore, not adequate for the evaluation of residents' exposure. Moreover it is very difficult to measure the aircraft noise by WECPNL due to the complicated calculating procedures if automatic measuring system is not used. Accordingly. this study aims to propose alternative evaluation procedure for the aircraft noise. To achieve this purpose, the data measured by automatic measuring system were gathered and calculated with three evaluation procedures : WECPNL $L_{eq}$ and $L_{dn}$, and the results calculated from different methods were compared and analyzed.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.5 s.110
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• pp.503-513
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• 2006

The duration time of aircraft noise event is also an important factor for the evaluation of civil aircraft noise, which is considered as a notable characteristic of military aircraft noise. SEL is proved as a suitable noise metric for the measuring military aircraft noise of various flight pattern considering the duration time of noise event. This study reviews whether SEL is a suitable for measuring civil aircraft noise and study shows SEL is fairly compensating the duration time of civil aircraft noise event for the evaluation of aircraft noise. Noise metric for the evaluation aircraft noise based on SEL is more appropriate than based on $L_{MAX}$ for compensating duration time of noise event either military aircraft or civil aircraft. In this reason, current formula of WECPNL based on energy average of measured $L_{MAX}$ for the evaluation of aircraft noise impact in 'Test Method of Noise and Vibration of Korea' is recommended to be amended to formula of WECPNL based on energy average of measured SEL considering compensation of noise event duration time, if WECPNL is not based on measured EPNL, a metric compensating duration time.