• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 추계학술대회 논문집
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• pp.78-79
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• 2011

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2013년도 추계학술대회 논문집
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• pp.491-492
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• 2013

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2013년도 추계학술대회 논문집
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• pp.477-478
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• 2013

• 한국음향학회지
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• 제24권7호
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• pp.371-378
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• 2005

본 연구에서는 면내 진동하는 감쇠 단을 갖는 보에서 진동파워의 크기와 방향을 나타내는 면내 진동인텐시티를 측정하였다. 보의 면내 진동인텐시티 측정 방법으로서 3가지 다양한 방법을 적용하였다. 이러한 방법들은 2개의 가속도계 선형 배열을 이용하는 가속도계배열법과 하나의 가속도계를 갖고 주파수응답함수를 이용하는 주파수응답함수법 그리고 기준 가속도를 고정시키고 다른 하나의 가속도계를 이용하는 기준가속도계법 들이다. 본 연구에서는 이러한 방법들을 적용하여 보의 진동인텐시티 공간 분포를 측정하여 비교하였으며, 또한 가진 점에서 주어지는 입력 파워와 비교를 통하여 적용 가능성을 확인하였다. 이러한 결과들로부터 보의 면내 진동인텐시티를 측정하기 위하여 가속도계배열법뿐만이 아니라 주파수응답함수법과 기준가속도계법 또한 효과적으로 사용될 수 있음을 보였다.

• 한국소음진동공학회논문집
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• 제20권1호
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• pp.74-82
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• 2010

Power flow analysis(PFA) methods have shown many advantages in noise predictions and vibration analysis in medium-to-high frequency ranges. Applying the finite element technique to PFA has produced power flow finite element method(PFFEM) that can be effectively used for analysis of vibration of complicated structures. PFADS(power flow analysis design system) based on PFFEM as the vibration analysis program has been developed for vibration predictions and analysis of coupled structural systems. In this paper, to improve the function of vibro-acoustic coupled analysis in PFADS, the PFFEM has been extended for analysis of the interior noise problems in the vibro-acoustic fully coupled systems. The vibro-acoustic fully coupled PFFEM formulation based on energy coupled relations is extended to structural system model by using appropriate modifications to structural-structural, structural-acoustic and acoustic-acoustic joint matrices. It has been applied to prediction of the interior noise in two room model coupled with panels, and the PFFEM results are compared to those of statistical energy analysis(SEA).

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 추계학술대회논문집
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• pp.767-770
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• 2006

To predict vibrational energy density of simple structural-acoustic coupled systems in medium-to-high frequency ranges, Power Flow Finite Element Method(PFFEM) is used, and PFFEM sofiware, PFADS has been developed for the vibration predictions and analysis of coupled system structures in medium-to-high frequency ranges. However, it needs to consider vibro-acoustic coupled analysis to get more accurate results. Prior to implement vibro-acoustic coupled analysis functions in PFADS, research on vibro-acoustic coupled analysis using PFFEH is performed for simple models. These predictions include the indirect transmission path associated, and also the direct transmission path, and the formulation is extended to structural system model by using appropriate modifications to structural-acoustic and acoustic-acoustic joint matrices. Concerning the waves in plate and acoustic, it is possible to calculate the structural-acoustic full matrix of a model using PFFEM, and the formulations developed are implemented for two rooms surrounded by plates.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 춘계학술대회논문집
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• pp.901-904
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• 2007

The power flow analysis (PFA) can be effectively used to predict structural vibration in medium-to-high frequency ranges. In this paper, vibration experiments have been performed to observe the analytical characteristics of the power flow analysis of the vibration of various coupled plates. Those plates include two plates coupled with angles of $90^{\circ}$\;and\;30^{\circ}$, respectively. In the experiment, the loss factor and the input mobility at a source point on each coupled plate have been measured. The data for the loss factors have been used as the input data to predict the vibration of the coupled plates with PFA. The frequency response functions have been measured over the surface of the coupled plates. The comparison between the experimental results and the predicted PFA results for the frequency response functions has been performed.

• 한국소음진동공학회논문집
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• 제18권4호
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• pp.400-410
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• 2008

Reduction of structure-borne noise in the compartment of a car is an important task in automotive engineering. Many methods which analyze noise transfer path have been generally used for structure-borne noise. These methods are useful in solving particular problem but do not quantify the effectiveness of vibration isolation for each isolator of a vehicle. To quantify the effectiveness of vibration isolation, the vibrational power flow measurement has been used for a simple isolation system or a laboratory based isolation system. This paper identifies the transfer path of booming noise in a SUV. The powertrain used for test has a in-line 4cylinder engine and 5-shift auto-transmission. This powertrain is transversely supported by four isolators. We calculated the energy flow throughout four isolator by the measurement of power flow and the contribution of energy flow at each isolator.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.517-520
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• 2004

The power flow analysis(PFA) can be effectively used to predict structural vibration in medium-to-high frequency ranges. In this paper, vibration experiment has been performed to observe the analytical characteristics of the power flow analysis of the vibration of a plate. In the experiment, the loss factor of the plate and the input mobility at a source point have been measured. The data for the loss factor has been used as the input data to predict the vibration of the plate with PFA. The frequency response functions have been measured over the surface of the plate. The comparison between the experimental results and the predicted results for the frequency response functions showed that PFA can be an effective tool to predict structural vibration in medium-to-high frequency ranges.

• 전자공학회논문지SC
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• 제49권2호
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• pp.26-37
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• 2012

본 연구에서는 준설토 탈수를 촉진시키기 위하여, 크기와 구동 주파수에 따라 임피던스 값이 크게 변화하는 PVDF film을 진동시키는 파워 드라이버를 개발하였다. PVDF film actuator를 구동하기 위한 파워 드라비버 IGBT를 이용하여 Full-Bridge 회로로 구현하였으며, R-L-PVDF Film으로 구성된 임피던스 정합 회로를 구현하여 PVDF Film에 최대한 많은 전력이 인가될 수 있도록 설계하였다. 개발한 파워 드라이버로 PVDF film actuator를 구동하여 준설토의 탈수 실험을 진행한 결과, 자연 탈수와 비교할 때 탈수 시작 후 30분 동안 약 3배 빠른 탈수 효과를 확인할 수 있었고, 개발한 PVDF film actuator 구동용 파워 드라이버를 이용하여 진동을 유발하는 준설토 탈수 장치에 적용할 수 있음을 확인하였다.