• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계 학술대회논문집(수송기계편)
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• pp.122-125
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• 2005

This study is an measurement and prediction of transmission loss through dash panel with multi-path in a vehicle. Measurement results of transmission loss are derided by sound power measured using the sound intensity method under locating a sound source in the anechoic room and reverberant room, respectively. Prediction one is decided by multi-path analysis of dash panel composed by a various part of materials and complicated shape. Finally, two results show a great agreement between measured and predicted transmission loss.

• 한국화재조사학회논문지
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• 제11권1호
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• pp.83-88
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• 2008

차량화재의 발화지점은 크게 엔진룸과 승객실로 볼 수 있다. 엔진룸에서 발생된 차량화재의 경우 방화벽이 엔진룸과 승객실 사이에 설치되어 있으므로 승객실로 전이는 약 10~15분 정도로 지연되는 것이 일반적이다. 엔진룸은 그 차량의 구동 방식에 따라 종치형과 횡치형으로 배열되는데 이들 엔진 배열에 따라 화염이 전이되는 과정이 각각 다르게 나타나고 좌우 대시 패널에 나타난 소손정도 또한 다르게 나타난다. 따라서 엔진룸에서 발생된 차량 화재 감식시 좌우 대시패널의 소손정도를 먼저 파악하는 것이 발화지점을 빠르게 찾는 방법인 것으로 사료된다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 춘계학술대회 논문집
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• pp.526-531
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• 2011

A dash panel component, close to passengers, plays a very important role to protect heat and noise from a power train. Meanwhile, it is also a main path that transfers vibration energy and eventually radiates acoustic noise into the cavity. Therefore, it seems important to provide an optimal design scheme incorporating sound packages such as dash isolation pad and carpet, as well as structures. The present study is the extension of the previous investigation how design variables affect sound radiation, which was carried out using the simple plate and framed system. The system taken into account in this paper is a dash panel component of a sedan, which includes A pillar, front side member, dash panel and the corresponding sound packages. Design variables such as panel thickness and sound package layers are investigated how they are related for the better radiation performance (i.e. structure-borne) and sound transmission loss (i.e. air borne).

• 한국음향학회:학술대회논문집
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• 한국음향학회 2004년도 추계학술발표대회논문집 제23권 2호
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• pp.191-194
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• 2004

This study Is an measurement and prediction of transmission loss through dash panel with multi-path in a vehicle. Measurement results of transmission loss are decided by sound power measured using the sound intensity method under locating a sound source in the anechoic room and reverberant room, respectively. Prediction one is decided by multi-path analysis of dash panel composed by a various part of materials and complicated shape. Finally, two results show a great agreement between measured and predicted transmission loss.

• 한국소음진동공학회논문집
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• 제22권1호
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• pp.22-28
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• 2012

While a dash panel component, close to passengers, plays a very important role to protect heat and noise from a power train, it is also a main path that transfers vibration energy and eventually radiates acoustic noise into the cavity. Therefore, it is important to provide optimal design schemes incorporating sound packages such as a dash isolation pad and a floor carpet, as well as structures. The present study is the extension of the previous investigation how design variables affect sound radiation, which was carried out using the simple plate and framed system. A novel FE-SEA hybrid simulation model is used for this study. The system taken into account is a dash panel component of a sedan vehicle, which includes front pillars, front side members, a dash panel and corresponding sound packages. Design variables such as panel thicknesses and sound packages are investigated how they are related to two main NVH indexes, sound radiation power(i.e. structure-borne) and sound transmission loss(i.e. air borne). In the viewpoint of obtaining better NVH performance, it is shown that these two indexes do not always result in same tendencies of improvement, which suggests that they should be dealt with independently and are also dependent on frequency regions.

• 한국소음진동공학회논문집
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• 제20권10호
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• pp.931-939
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• 2010

A dash panel plays an important role to protect noise as well as heat. Meanwhile, it is also the most important path that transfers energy to the interior cavity, so that some of noises are transferred via air and its structural vibration becomes a major issue. From the viewpoint of NVH performance, simplified structures analogues to the dash wall are dealt with. Stiffeners, damping sheets and sound packages attached to a flat panel are taken into account as design variables. Structural radiation characteristics(thus, structure borne) such as radiation efficiency and radiation power are mainly discussed. For the case when an excitation is applied on a frame that surrounds the panel, it is shown that the radiation efficiency increases by attaching a stiffener to the panel, which is similarly found from the case when a panel is directly excited. It seems more effective to attach damping sheets along the boundary area of the panel rather than its middle area. The radiation efficiency of sound packages may make a dominant contribution to transmission loss as well as sound radiation. Experimental work was carried out to verify the results based on the simulation study.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2008년도 추계학술대회 논문집
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• pp.81-84
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• 2008

In this paper, the techniques for implementing the dashboard functions of a SHEV bus are development by using a touch panel. The algorithms for controlling linearly the angle of each gauge according to the measured sensors values. The hardware technique presentation and the development for implementing the On/Off information of each telltale lamp in the touch panel. The system is implemented by the 32-bit DSP, and it is installed and tested on the real SHEV bus. Also on/off switching status of all telltale lamps cab be investigated through the touch panel.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2012년도 춘계학술대회 논문집
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• pp.667-671
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• 2012

Low frequency noises (up to about 200 Hz) mainly occur due to particular modes, resulting in booming noises, and in general the solutions may be found based on mode controls where conventional methods such as FEM can be used. However, at higher frequencies between 0.3~ 1 kHz, as the number of modes rapidly increase, radiation characteristics from structures, performances of damping sheets and sound packages may be more crucial rather than particular modes, and consequently the conventional FEM may be less practical in dealing with this kinds of structure-borne problems. In this context, so-called 'mid-frequency simulation model' based on FE-SEA hybrid method is studied and validated. Energy Transmission loss (i.e. air borne noise) is also studied. A dash panel component is chosen for this study, which is an important path that transfers both structure-borne and air borne energies into the cavity. Design modifications including structural modifications, attachment of damping sheets and application of different sound packages are taken into account and the corresponding noise characteristics are experimentally identified. It is found that the dash member behaves as a noise path. The damping sheet or sound packages have similar influences on both sound radiation and transmission loss. The comparison between experiments and simulations shows that this model could be used to predict the tendency of noise improvement.

• 한국소음진동공학회논문집
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• 제22권11호
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• pp.1071-1077
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• 2012

Low frequency noises(up to about 200 Hz) such as booming are mainly caused by particular modes, and in general the solutions may be found based on mode controls where conventional methods such as FEM can be used. However, at higher frequencies between 0.3~1 kHz, as the number of modes rapidly increases, radiation characteristics from structures, performances of damping sheets and sound packages may be more crucial rather than particular modes, and consequently the conventional FEM may be less practical in dealing with this kinds of structure-borne problems. In this context, so-called 'mid-frequency simulation model' based on FE-SEA hybrid method is studied and validated to reduce noise in this frequency region. Energy transmission loss(i.e. air borne noise) is also studied. A dash panel component is chosen for this study, which is an important path that transmits both structure-borne and air borne energies into the cavity. Design modifications including structural modifications, attachment of damping sheets and application of different sound packages are taken into account and the corresponding noise characteristics are experimentally identified. It is found that the dash member behaves as a noise path. The damping sheet and sound packages have similar influences on both sound radiation and transmission loss. The comparison between experiments and simulations shows that this model could be used to predict the tendency of noise improvement.