• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 춘계학술대회논문집
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• pp.725-727
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• 2005

In this study, the sound transmission characteristics of honeycomb structures are investigated with changing its thickness, shear modulus, and surface density. Theoretical predictions of aluminum honeycomb panels are compared with experimental results, which can furnish an in depth understanding of the insulation characteristics of honeycomb panels.

• 대한기계학회논문집A
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• 제34권12호
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• pp.1931-1936
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• 2010

한국형 틸팅열차에는 고속화와 경량화를 위하여 허니콤 복합재가 처음으로 사용된다. 틸팅열차의 측벽은 탄소섬유강화 에폭시층과 접착된 알미늄 허니콤 및 노멕스 허니콤 판재를 주 요소로, 유리면이 적층된 복합 적층재이다. 본 연구에서는 ASTM E2249-02에 근거하여 알미늄 및 노멕스 허니콤 복합 적층재의 층별 인텐시티 투과손실을 측정한다. 질량법칙편차를 이용하여 허니콤 복합재의 중량 대비 차음 성능을 평가하고, 차음 측면에서 알미늄 허니콤 복합재가 기존의 주름강판을 대체할 수 있는지의 가능성을 검토한다. 본 연구를 통하여 얻은 허니콤 복합 적층재의 차음성능 자료는 향후 틸팅 열차의 실내 소음 대책 수립에 활용될 것이다.

• Advanced Composite Materials
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• 제18권1호
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• pp.1-20
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• 2009

This paper describes the results of experiments and numerical simulation studies on the impact and indentation damage created by low-velocity impact subjected onto honeycomb sandwich panels for application to the BIMODAL tram. The test panels were subjected to low-velocity impact loading using an instrumented testing machine at six energy levels. Contact force histories as a function of time were evaluated and compared. The extent of the damage and depth of the permanent indentation was measured quantitatively using a 3-dimensional scanner. An explicit finite element analysis based on LS-DYNA3D was focused on the introduction of a material damage model and numerical simulation of low-velocity impact responses on honeycomb sandwich panels. Extensive material testing was conducted to determine the input parameters for the metallic and composite face-sheet materials and the effective equivalent damage model for the orthotropic honeycomb core material. Good agreement was obtained between numerical and experimental results; in particular, the numerical simulation was able to predict impact damage area and the depth of indentation of honeycomb sandwich composite panels created by the impact loading.

• 대한조선학회논문집
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• 제33권4호
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• pp.106-123
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• 1996

최근 초고속선을 비롯한 대형 경량구조물의 강도부재로 알루미늄하니콤 샌드위치판이 주목을 받고 있다. 이러한 새로운 구조를 설계에 도입하기 위해서는 이에 대한 각종 구조거동 특성을 알아야 한다. 본 연구에서는 알루미늄하니콤 샌드위치판에 대한 선형 탄성거동을 연구하기 위하여 정적 굽힘실험을 수행하였으며, 이 판의 좌굴 및 최종강도를 연구하기 위하여 1축 압축실험을 수행하였다. 또한, 하니콤 심재의 압괴 및 에너지흡수 특성을 분석하기 위하여 압괴실험도 수행하였다. 이러한 일련의 실험을 통하여 탄성학에 기초한 이론식과 각종 실험식들의 샌드위치 구조에의 유용성을 확인하고 나아가서 간단한 설계지침을 제시하였다.

• 동력기계공학회지
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• 제12권4호
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• pp.46-51
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• 2008

Honeycomb panel has a constructive advantage because it is constructed with a honeycomb core, so it has relatively higher strength ratio to weight. Therefore honeycomb panel has been used as the light weight panels in the high-speed railway technology and high-speed ship like as cruise yachts. Also it has been used in the aircraft and aerospace industry as a structural panel because light weight structure is indispensible in that field of industry. Recently, the honeycomb panel is embossed in the viewpoints of high oil prices as the lightweight panel of the transport machine, however the sound insulation capacity of the honeycomb panel is poorer than those of uniform and another sandwich panels. In this paper a method to improving the sound absorption coefficient of a honeycomb panel Is studied by using the Helmholtz resonator. The sound absorption coefficients for some kinds of honeycomb cores are demonstrated by the normal incident absorption coefficient method.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.2185-2190
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• 2008

In a high speed train, multi-layered panels for floor, side wall and roof are important sound insulating part. As these multi-layered panels require high bending strength vs. weight, corrugated steels or aluminium honeycomb panel are generally used. However, with some inevitable factors, these panels show lower sound insulation performance than that of the plate with the same weight. Transmission loss(TL) often severely decreases in a particular frequency range because of the decrease of the critical frequency, occurrence of local resonance modes and cavity resonance modes, which are not shown in a plate. In this study, frequency range and cause of the TL drop are investigated on the corrugated and honeycomb panels.

• 비파괴검사학회지
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• 제29권4호
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• pp.269-282
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• 2009

This paper presents a novel approach for Lamb wave based structural health monitoring(SHM) in honeycomb aluminum panels. In this study, a suite of three signal processing algorithms are employed to improve the damage detection capability. The signal processing algorithms used include wavelet attenuation, correlation coefficients of power density spectra, and triangulation of reflected waves. Piezoelectric transducers are utilized as both sensors and actuators for Lamb wave propagation. These SHM algorithms are built into a MatLab interface that integrates and automates the hardware and software operations and displays the results for each algorithm to the analyst for side by side comparison. The effectiveness of each of these signal processing algorithms for SHM in honeycomb aluminum panels under a variety of damage conditions is then demonstrated.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 추계학술대회논문집
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• pp.464-473
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• 2006

This paper summarises theoretical and experimental work on the feedback control of sound radiation from honeycomb panels using piezoceramic actuators. It is motivated by the problem of sound transmission in aircraft, specifically the active control of trim panels. Trim panels are generally honeycomb structures designed to meet the design requirement of low weight and high stiffness. They are resiliently-mounted to the fuselage for the passive reduction of noise transmission. Local coupling of the closely-spaced sensor and actuator was observed experimentally and modelled using a single degree of freedom system. The effect of the local coupling was to roll-off the response between the actuator and sensor at high frequencies, so that a feedback control system can have high gain margins. Unfortunately, only relatively poor global performance is then achieved because of localisation of reduction around the actuator. This localisation prompts the investigation of a multichannel active control system. Globalised reduction was predicted using a model of 12 channel direct velocity feedback control. The multichannel system, however, does not appear to yield a significant improvement in the performance because of decreased gain margin.

• 한국철도학회논문집
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• 제11권5호
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• pp.465-470
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• 2008

본 논문에서는 철도 차량용 허니콤 판재를 대상으로 음투과 손실을 검토한다. 허니콤재의 음투과 손실을 예측하는 데에는 등가 직방성 평판 모델과 등가 질량법칙을 적용한다. 음투과 손실의 예측치를 측정치와 비교하여 예측 모델의 신뢰도와 한계를 검토한다. 또한 일치효과와 국부공진 효과가 차음성능에 미치는 효과를 검토한다. 본 연구는 국부공진 주파수대역을 적절히 적용한다면, 등가 직방성 평판 모델을 허니콤재의 음투과손실 예측모델로 사용 할 수 있음을 보인다. 최종적으로, 국부 공진에 의한 차응성능의 급격한 저하에 대한 대책을 제시하고 그 차음 성능에 대한 효과를 분석한다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제8권6호
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• pp.554-562
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• 2016

Recently, regulations pertaining to the noise and vibration environment of offshore plants have been strengthened. For example, the NORSOK standards have been applied, which are very strict regulations that are comparable to those applied to passenger ships. Furthermore, the use of porous materials, such as those used in most of the current insulating panels, has been forbidden. Therefore, honeycomb-backed Micro-Perforated Plates (MPPs) are now regarded as next-generation absorber materials. This paper reports the results of parametric studies that were performed using numerical methods to determine the effect of the thickness on the performance of a honeycomb panel and the effect of the perforation ratio on the MPP performance. The numerical results were verified through experiments. Finally, we propose a combined honeycomb/MPP panel where the MPP is placed between upper and lower honeycomb panels and one end surface is also replaced with an MPP.