• 소음진동
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• 제6권6호
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• pp.727-733
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• 1996

Machines installed in various structures emit airborne sound and structureborne sound and are major source of noise and vibration. Especially when machines are installed upon a flexible foundation, most of noise and vibration are due to transmission of structureborne sound. Therefore, characterization and measurement of structureborne sound source level are necessary for controlling noise and vibration. But structureborne sound from vibrating machine is strongly coupled to the supportingstructure. This paper proposes the method of estimating the supporting sturcture's dynamic character- istic and structureborne sound source level for machine installed system without separating the machine, resilient mount and foundation.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 춘계학술대회논문집
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• pp.398-402
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• 2005

Structureborne noise induced by shipboard equipment is one of the most significant noise source of ships and can be effectively reduced by resiliently mounting them. In this paper, the pole parameter method is investigated for estimating the structureborne noise reduction of resiliently mounted equipment. In addition, we suggest how to evaluate pole parameters from dimensional and material information of each component consisting of resiliently mounted equipment. To validate and discuss the proposed method numerical analysis for single and double resiliently mounted equipment systems using both pole parameter method and FEM have been done.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1991년도 춘계학술대회논문집; 한국해사기술연구소, 대전; 1 Jun. 1991
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• pp.31-39
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• 1991

When predicting shipboard noise levels, the accuracy depends largely on the value of the structureborne noise transmission loss. Although empirical formulars are frequently used because of their simplicities, researches on the analytical methods to estimate the transmission loss of structureborne noise such as wave guide theory and SEA has long been one of the major topics in shipboard acoustics to overcome the inherent limitations of empirical ones. This paper describes an application of SEA to predict the transmission loss of the structurebornenoise of a simple ship-like structural model consisted of 22 flat plates. The result shows that discrepancies between experimental and theoretical transmission losses are less than 3 dB.

• 대한조선학회논문집
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• 제29권1호
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• pp.113-122
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• 1992

선박소음을 예측하는 과정중에서 고체소음 전달해석은 직접적으로 예측결과의 정도에 영향을 미치고 있다. 이에 대한 계산 방법으로서 경험식이 그 간편성 때문에 자주 사용되고 있지만 자체의 한계성 때문에 이론적 해석방법(Wave guide theory, SEA등)들에 대한 연구가 선박음향학 분야에서 꾸준히 수행되어 왔다. 본 연구에서는 SEA를 이용하여 22개의 plate로 구성된 선체구조의 단순모델을 대상으로 고체소음 전달손실에 대한 이론적 계산 및 실험적 산정을 수행하였다. 계산치와 실험치의 비교결과는 3 dB이내의 좋은 일치를 보여 주었다.

• 한국소음진동공학회논문집
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• 제19권8호
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• pp.802-808
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• 2009

In this paper, the experimental study on the identification of noise sources and noise transmission paths was carried out for the cabin noise control of construction equipment. In order to investigate noise and vibration characteristics of cabin structure, sound absorption, transmission, and radiation tests were performed using cabin assembly models. The noise/vibration source levels were obtained from the real cabins of wheel loader and excavator. Using transfer functions of cabins and real cabins' source data, cabin noise was decomposed into airborne and structureborne noise transmissions. Finally noise sources and major transmission paths were successfully identified for wheel loader and excavator's cabins.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 춘계학술대회 논문집
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• pp.84-89
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• 2009

In this paper, the experimental study on the identification of noise sources and noise transmission paths was carried out for the cabin noise control of construction equipment. In order to investigate noise and vibration characteristics of cabin structure, sound absorption, transmission, and radiation tests were performed using cabin assembly models. The noise/vibration source levels were obtained from the real cabins of wheel loader and excavator. Using transfer functions of cabins and real cabins' source data, cabin noise was decomposed into airborne and structureborne noise transmissions. Finally noise sources and major transmission paths were successfully identified for wheel loader and excavator's cabins.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.385-386
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• 2014

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 춘계학술대회논문집
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• pp.825-830
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• 2000

In this article, the underwater radiated noise of the submerged cylindrical shell model is investigated using hull transfer functions which were defined in accordance with structureborne and airborne noise propagation paths. This method is very useful tool as the prediction of radiated noise from submerged structures in design stage. This approach is verified by experimental model and its measurement results.

• 소음진동
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• 제3권2호
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• pp.155-161
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• 1993

The vibration generated by the machinery on board is transmitted to the hull and into the water. At the early design stage, the prediction of the hull vibration and the radiated noise level is very important to reduce their levels. In this study, SAE(Statistical Energy Analysis) technique is applied to predict structureborne noise level of the hull considering fluid loading. Rayleigh integral is applied to predict the radiated noise level. The results of comparision between the predictions and measurements for the reinforced cylindrical shell have shown good agreements.

• 대한조선학회지
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• 제27권2호
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• pp.78-86
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• 1990

본 연구에서는 도파관 이론을 이용하여 선체구조를 대상으로 고체 소음의 전달 손실 문제를 다루었다. 선체를 음향 도파관 계로 모형화 할 때, 단면 모드는 해당계의 경계조건 즉 늑골에서의 구속조건에 의해 결정된다. 본 논문에서는 이와 같은 구속조건을 완화시켜 단면 모드를 조절할 경우, 도파관 이론이 저주파수 영역에 대하여도 계측치와 비교적 일치하는 결과를 주고 있음을 확인하였으며, 동시에 국부 요소의 질량과 감쇠의 변화가 고체소음의 전달손실에 미치는 영향을 살펴보았다.