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A Study for Examination of Road Noise Prediction Results According to 3-d Noise Prediction Models and Input Parameters (3차원 소음예측모델 및 입력변수 변화에 따른 도로소음 예측결과 검토에 대한 연구)

  • Sun, Hyosung
    • Journal of Environmental Impact Assessment
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    • v.23 no.2
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    • pp.112-118
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    • 2014
  • The application of a 3-d noise prediction model is increasing as a tool for performing actual noise assessment in order to investigate the noise impact of the residential facility around a development region. However, because the appropriate plans of applying a 3-d noise prediction model is insufficient, it is important to secure the reliability of the noise prediction results generated by a 3-d noise prediction model. Therefore, this study is focused on examining a 3-d noise prediction model, and a prediction equation and input data in it. For this, the 3-d noise prediction models such as SoundPLAN, Cadna-A, IMMI is applied in road noise. After the contents of road noise equations, input data of road noise source, and input data of road noise barrier are understood, the road noise prediction results are compared and examined according to the variation of 3-d noise prediction model, road noise equation, and input data of road noise source and road noise barrier.

A Comparison of Noise Level by Noise Measuring Methods (소음측정방법에 따른 평가소음도 비교)

  • Shim, Chur Goo;Roh, Jae hoon;Park, Jung Gyun
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.5 no.2
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    • pp.128-136
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    • 1995
  • The purpose of this study is to evaluate the difference of noise level according to noise measuring methods in the noisy working environments. Sound pressure level(SPL), equivalence sound level(Leq) and personal noise exposure dose(Dose) in the fifty-nine unit workplaces of the twenty-eight industries were measured and relating factors which were affected noise level were investigated. The results were as follows ; 1. The noise levels were $88.70{\pm}5.68dB(A)$ by SPL, $89.07{\pm}5.41dB(A)$ by Leq and $89.07{\pm}5.69$ by Dose. The differences of noise levels by three measuring methods were statistically significant(P<0.001) by repeated measure ANOV A. 2. Comparing with noise levels by general classes of noise exposure, noise levels of continuous noise were $89.14{\pm}5.19dB(A)$ by SPL, $89.45{\pm}4.65dB(A)$ by Leq and $90.04{\pm}5.09$ by Dose. Noise levels of intermittent noise were $87.90{\pm}6.52dB(A)$ by SPL, $88.40{\pm}6.63dB(A)$ by Leq and $90.10{\pm}6.80$ by Dose. The differences noise level of noise measuring methods by general classese of noise exposure were statistically not significant by repeated measure ANOV A. 3. Interaction between general classese of noise exposure and noise measuring methods for noise level was not statistically significant by repeated measure ANOVA. And the noise level by noise measuring methods were statistically significant by repeated measure ANOV A(P<.001) 4. Comparing with noise levels by unit workplace size, noise levels of large unit workplace were $90.73{\pm}5.87dB(A)$ by SPL, $91.32{\pm}5.50dB(A)$ by Leq and $91.82{\pm}6.06$ by Dose and noise levels of middle unit workplace were $88.31{\pm}5.26dB(A)$ by SPL, $88.41{\pm}4.83dB(A)$ by Leq and $89.69{\pm}5.05$ by Dose. And noise levels of small unit workplace were $94.89{\pm}4.10dB(A)$ by SPL, $85.35{\pm}4.11dB(A)$ by Leq and $86.87{\pm}4.98$ by Dose. The noise level differences of noise measuring methods by unit workplace size were statistically significant by repeated measure ANOV A(P<.05). 5. The noise level by noise measuring methods were statistically significant by repeated measure ANOV A(P<.001). But Interaction between workplace size and noise level measuring methods for noise level was not statistically significant by repeated measure ANOVA. According to the above results, there was a difference of the noise level among the three measuring methods. Therefore we must use the personal noise exposure dose using by noise dose meter, possible, to prvent occupational hearing loss in noisy working environment.

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A Study on the Effect of Low Noise Wheel for the Noise and Vibration Reduction (방음차륜의 소음진동 저감효과에 관한 연구)

  • 김재철;유원희;문경호
    • Journal of KSNVE
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    • v.10 no.4
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    • pp.629-635
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    • 2000
  • Wheel /rail interaction has been known as a major source of railway noise. In this paper, a low noise wheel structure is developed and its effect on noise reduction is investigated. The developed low noise wheel employees a rubber material inserted into a steel rim or mounted on the wheel surface. Since the low noise wheel has low stiffness and high damping ratio compared to a solid wheel, the measurement results show that it reduces the rolling and squeal noise. It turns out that the proposed wheel could reduce interior noise level by 4∼5dB(A) and vehicle vibration level by 7∼10 dB. Although the proposed structure seems to be promising in noise reduction of railway vehicles, the low noise wheel is to be verified in endurance and cost effect.

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Community Noise : Transpotation Noise (생활소음종합대책 : 교통소음)

  • Son, Jung-Gon;Kim, Jung-Soo;Kim, Hong-Chan
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • pp.89-101
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    • 2006
  • This study is a part of ???A study of the community noise:new guideline and policy' which have three main topics and ten sub-topics. Accordingly this part deals with a transpotation noise specifying road traffic ,railroad and aircraft noise, respectively. At first, the ,roadside traffic noise of whole country in 2004 ,22 major cities of total 29 was exceeded the envionmetal noise standards, 55dB(A) at night time ,therefore 24 milion people ,52.4% of korean, who reside at roadside estimates to be exposured the basic problems of this serious noise polluation comes from:: i)It's very limited noise mitigation measures against to continuously increase the number of automobile yearly. ii) and at beginning of road design, It has been neglect to introduce the anti-noise design and layout of road structural scheme as gadient,cutting and viaduct,embankment and zonning of roadside land-buffer area and also re-designation of noise sensitive areas,etc. Secondly ,concerned with the railroad trafffic noise, a inhabitants who are over the envionmetal noise limits,70dB(A), 65 dB(A) in day and night for 34 locations of mayor cities was exposured of 167,000 and 329,000 respectively. With the development of noise mitigation schemes in line with this study it is likely that noise monitoring system needs new installation as well as common use of noise assessment index with $L_{MAX}\;and\;L_{EQ}$. Lastly,noise complaints of millitary aircraft has been rapidly increasing ,so 2.9%(1.4 minion) person demands a compansation of \2,133 billion complying with their requirements we suggest to minimise the airport noise that is to develop of noise abatement procedure ,to make new noise index, to increase budget for house insulations and also to more increase of those the noise monitoring system and to unify the management etc.

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A Study on the Fitness of Road Traffic Noise Formulas for Noisemap (소음지도 작성을 위한 도로교통소음 예측식의 적합성 연구)

  • Kim, Hwa-Il
    • Journal of Environmental Science International
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    • v.16 no.7
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    • pp.823-830
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    • 2007
  • Traffic noise is a kind of noise caused by cars, trains and aircraft. Among them, noise produced by cars is the most important factor in cities. According to the National Institute of Environmental Research(NIER)'s survey, Road traffic noise levels in Susan are the highest of all the cities in Korea. So, appropriate measures for road traffic noise reduction is required. For this purpose, the construction of a noise map in Susan will playa vital role. However, road traffic noise formulas are constructed considering regional characteristics such as each country road's environment and vehicle quality. Therefore, prior to constructing a noise map in Susan, examination processes about each formula constituent status and estimation process are required preferentially. In this research, the basic first stage is to estimate Susan's road traffic noise. First, investigate characteristics of each road traffic noise estimate and using this, a noise map is constructed for road traffic noise in Susan. Then the adaptation of a road traffic noise formula is evaluated.

Characteristics of Noise Exposure Level on Workers of Tunnel Construction Sites (일부 터널건설현장 근로자의 소음노출 수준에 대한 고찰)

  • Kim, Kab Bae;Jang, Jae-Kil
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • pp.739-744
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    • 2013
  • The aim of this study is to evaluate the noise level from the machines used for tunnel construction and to analyze the noise exposure level of workers engaged in tunneling works. The sound level meter and noise dosimeters was used for the monitoring of noise in the tunneling work sites. The average noise from jumbo drill was 113.0 dE(A), the noise from pay loader was 92.4 dB(A), the noise from backhoe was 99.9 dB(A) and the noise from shotcrete machine was 94.3 dE(A). The tunneling workers were exposed to 66.9~94.9 dB(A) of noise and other workers exposed to less than 90 dB(A) of noise. Jumbo drill operators were exposed to to 82.5~84.2 dB(A) of noise, backhoe operators were exposed to 70.2~94.9 dB(A) of noise, shotcrete machine operators were exposed to 68.2~74.7 dB(A) of noise and pay loader operators were exposed to 59.2~81.3 dE(A) of noise.

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Prediction of the Noise Levels for a Plant (공장 소음도 예측)

  • 윤세철;김태구;오종민
    • Journal of the Korean Society of Safety
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    • v.15 no.3
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    • pp.88-95
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    • 2000
  • The level of noise produced by machinery and its arrangement insides a factory is indicated to be a maximum of 96.1 dB(A). The maximum level of noise from a commoner's house outside the factory is shown to be 62.9 dB(A), which exceeds 60 dB(A), the permitted limit of noise level in a time period of day. us study has predicted the level of noise reduction according to a step by step prevention plan by considering the characteristics of the causes of noise, the permitted limit of noise levels, problems and economical efficiency attendant upon the noise prevention measures. Establishing target levels of noise each of the three steps of the noise prevention plan. The predicted level of noise at the place of a commoner's house in accordance with the first step is 50.0 - 59.0 dB(A), and can satisfy the permitted limit of noise in a time period of the day. In taking prevention measures for the second step, the noise level is 50.7 - 53.6 dB(A) which is less than 55 dB(A) in a time period of the evening, the permitted limit of noise in a time period of night., and it can meet 47.4 - 50.3 dB(A) in the third step.

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Sound Quality Evaluation for Laundry Noise by a Virtual Laundry Noise Considering the Effect of Various Noise Sources in a Drum Washing Machine (소음원의 영향이 고려된 가상 세탁음 제작을 통한 드럼 세탁기의 음질 인덱스 구축)

  • Jeong, Jae-Eun;Yang, In-Hyung;Fawazi, Noor;Jeong, Un-Chang;Lee, Jung-Youn;Oh, Jae-Eung
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.22 no.6
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    • pp.564-573
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    • 2012
  • The objective of this study is to determine the effect for the sound quality according to the noise source and to build the sound quality index of the laundry noise. In order to compare laundry noise among the influence of noise sources, we made virtual laundry noises by synthesizing an actual laundry noise and each noise source such as a dropping noise, water noise, motor noise and circulation pump noise. We conducted a listening test by customers using virtual laundry noises. As a result of listening test, we found that the dropping noise has a decisive effect on the sound quality of the laundry noise. We conducted the multi regression analysis of sound quality for the laundry noise using the statistical data processing. It is verified to the reliability of the multi regression index by comparison with listening results and index results of other actual laundry noises. This study is expected to provide a guide line for improvement of the laundry noise.

The Development of an Automatic Noise Inspection System of a Rotating Engine Part Using OLE (OLE 기반 엔진 구동 부품의 자동 소음 검사 장비 개발)

  • 이상철;한성복;최성배
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.14 no.10
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    • pp.968-974
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    • 2004
  • Automakers have been forcing their suppliers to guarantee qualities of parts. Then, the suppliers have met the fundamental quality requirements such as dimensions and functions, but they could not sufficiently satisfy the automakers' noise requirements yet because automatic noise inspection systems were little successfully adopted In mass-production lines. This study tried to develop a system for automatically checking noise radiated from a rotating engine part and filtering parts emitting noise higher than criteria: the upper limits of a overall noise level or a noise spectrum. A commercial noise measurement system was used for measuring noise, and then the noise data was transmitted to a governing program through OLE(object, linking and embedding) functions. The governing program, belonging to a total noise inspection system managed the noise measurement and analysis. This system was successfully adapted for distinguishing bad parts according to the noise criteria.

Actual State and Characteristics of Indoor Noise Including Residents' Living in Apartment Units (아파트 단위주거 내부생활소음의 특성과 실태)

  • Choi, Yoon-Jung
    • Journal of the Korean housing association
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    • v.20 no.1
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    • pp.83-90
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    • 2009
  • The present study is a preliminary research improving the dwelling quality of apartment house as a kind of multi-family housing. The purpose of the study is to find out the actual state on characteristics of indoor noise including residents' living in apartment units. The method was field survey consisted of field measurements on equivalent noise level, observation on noise type, and interview on residents' responses. Field survey were carried out in 20 occupied apartment units from January to March 2007. The results are as follows. 1) Averages of indoor noise levels including residents' living noise were measured as $43.9{\sim}62.2\;dB(A)_{Leq5min}$, the average of each house except one was higher than the permissible level, 45 dB(A). 2) The noise types observed were mostly residents' living noise and classified into 'water hammer', 'living equipment noise', 'noise by family', 'hood noise', 'kitchen noise' in own unit, 'walking and talking noise in stairs and corridors', 'noise by neighborhood house', 'noise by the upper story' in building, and outdoor noise. 3) The residents showed slightly non-positive responses at 'noise by the upper story', 'noise by neighborhood house', 'water hammer', and 'noise by family'. Therefore, it is required to plan for preventing deterioration of the dwelling quality by residents' living noise in own unit as well as by neighborhood houses.