• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2010년도 춘계학술대회 논문집
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• pp.477-478
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• 2010

It was in the mid-1980s when the shipboard noise analysis was introduced to the Korean shipbuilding industry. Since then through the continued efforts of the industries in the last decades, native computational codes dedicated to the shipboard noise prediction have been developed based on empirical formula and/or sophisticated theories such as SEA and PFM. This paper addresses some problems in dealing with predicting shipboard noise and the way how to overcome the uncertainties in the prediction.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2002년도 추계공동학술대회논문집
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• pp.75-80
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• 2002

연안 선박의 선상근무 환경은 육상근무 환경에 비하여 매우 열악하여 선상근무 기피와 선원 고령화의 원인이 되고 있다. 특히 선박내 소음은 난청과 같은 직업병을 유발시키는 원인이 된다. 따라서 안락한 선상근무 환경 및 거주 환경의 확보를 통하여 선상근무 피로도를 경감시키는 것이 필요하다. 본 연구에서는 먼저 선박내 소음 및 진동의 실선 계측을 통하여 선상근무 환경을 체계적으로 평가한다. 그리고 선상근무 환경의 평가 겉과에 기초하여 선상근무 피로도 경감대책을 제안한다.

• 한국항해항만학회지
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• 제27권1호
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• pp.15-30
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• 2003

연안 경비함정의 선상근무 환경은 육상근무 환경에 비하여 매우 열악하여 선상근무 기피와 성원고령화의 원인이 되고 있다. 특히 선박내 소음은 난청과 같은 직업병을 유발시키는 원인이 된다. 따라서 안락한 선상근무 환경 및 거주 환경의 확보를 통하여 선상근무 피로도를 경감시키는 것이 필요하다. 본 연구에서는 먼저 선박내 소음 및 진동의 실선 계측을 통하여 선상근무 환경을 체계적으로 평가한다. 그리고 선상근무 환경의 평가 결과에 기초하여 선상근무 피로도 경감대책을 제안한다

• 대한조선학회 특별논문집
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• 대한조선학회 2006년도 특별논문집
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• pp.7-14
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• 2006

In recent years, shipboard noise control is attracting increasing attention to human environmental conditions and crew's opportunity for rest and recreation with work on board. In order to minimize the noise levels, careful attention have to be paid by the experts from initial design stage to the delivery. This paper describes the outlines of shipboard noise control including general characteristics of shipboard noise, measurement, evaluation, prediction, and control measures considering the noise transmission mechanism from source to receiver space.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 춘계학술대회논문집
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• pp.849-854
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• 2000

Statistical energy analysis is suitable for shipboard noise prediction in many respects. It could effectively model the large and complicated ship structures for noise analysis. This paper introduces the procedure of SEA for shipboard noise analysis gained from author's experiences in the past few years. Also, prediction accuracies of shipboard noise analysis using statistical energy analysis are discussed. It is found that the prediction results could be much improved when using the actual measured data of source levels and material properties such as loss factors, absorption coefficients and etc.

• 한국소음진동공학회논문집
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• 제24권7호
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• pp.509-516
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• 2014

This paper proposes estimation model of uncertainty in vibration measurement of shipboard equipment and analyzes the result of uncertainty estimation. Vibration of shipboard equipments affects underwater radiated noise that is important performance related to stealth of the naval vessel. Acceptance testing for shipboard equipment is required to guarantee the stealth performance of naval vessel. In measuring, detailed uncertainty estimation is essential to improve measuring reliability. Acceptance testing result of structure-borne noise and vibration is used to analyze uncertainty in vibration measurement of shipboard equipment.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 춘계학술대회논문집
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• pp.355-358
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• 2008

This study deals with a substantial problems with SEA modeling methods in shipboard noise predictions. As a first problems with respect to modeling, fineness of model that represents a real structure is numerically investigated by comparison among 3 models, Fine, Coarse and Simplified models. Comparison reveals that Fine model shows the lowest noise level among them since this model involve more energy transfer paths than the other models. Influence of in-plane wave is also examined by numerical comparison. It is clear that inclusion of in-plane wave affects the high frequency and the cabin far from a source.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 추계학술대회 논문집
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• pp.519-524
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• 2011

The aim of this study is to develop an automated program for noise prediction in shipboard compartments, for this purpose of calculating noise levels accurately and quickly. The program calculates sound power level at HVAC components based on the empirical method suggested by NEBB and utilizing the manufacturer's test data. The program developed uses the GUI functions to help in efficient modeling and calculation. To verify the reliability of developed program, the predicted data was compared with the measured data in shipboard compartments. As a result, the average difference between predicted and measured data is ${\pm}3dB$.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1990년도 추계학술대회논문집; 한양대학교, 서울; 24 Nov. 1990
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• pp.53-58
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• 1990

The use of spreadsheet packages for solving noise control problems has been cited by several authors, eg Saha[1] and Thornton[2]. The effectiveness of using spreadsheet packages compared with the traditional computer programs written in high level languages was demonstrated when applied to relatively simple problems, such as the selection of hearing protectors or the prediction of noise equation which includes logarithmic additions at most represents the physics of the problem. The simplicity of the governing equation together with the requirement to handle a vast amount of data are considered to be the major reasons for noise control engineers to use spreadsheet packages. Although shipboard noise prediction seems to be very complicated, the calculation procedure itself is, in essence, identical especially true for prediction methods based on empirical formulae[3,4], ie the procedure that consists of the three basic elements, ie source, path and receiver. This paper discusses the application of spreadsheet package LOTUS 1-2-3 to shipboard noise prediction problems. A utility program of the package is written using macro functions and is shown to be especially useful for noise control engineers who are unfamiliar with spreadsheet packages. In addition, a new type of empirical formula, to estimate structureborne noise transmission loss, is proposed.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 춘계학술대회논문집
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• pp.411-415
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• 2007

The reduction of airborne and structure-borne noise of a shipboard pump for a navel ship is very important because the noise levels of the pump must not exceed criteria such as MIL-STD. In this paper, several practical examples of reducing the noise levels are presented. The examples show that the inadequate rotor-balancing and shaft-alignment results in the increase of the structure-borne noise on all lower mounts. It is also found that the unequal loading on mounts can cause the dramatically increasing the noise levels on certain local positions. Since the piping system arrangement such as valve location, flexible joint, and elbow location affects on the noise measurement, care must be taken to minimize the unnecessary noise from the piping system.