• International Journal of Naval Architecture and Ocean Engineering
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• 제5권2호
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• pp.313-323
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• 2013

Offshore floating structures have so-called moonpool in the centre area for the purpose of drilling, installation of subsea structures, recovery of Remotely-Operated Vehicle (ROV) and divers. However, this vertical opening has an effect on the operating performance of floating offshore structure in the vicinity of moonpool resonance frequency; piston mode and sloshing mode. Experimental study based on model test was carried out. Moonpool resonance of floating offshore structure on fixed condition and motion free condition were investigated. And, the effect of cofferdam which is representative inner structure inside moonpool was examined. Model test results showed that Molin's theoretical formula can predict moonpool resonance on fixed condition quite accurately. However, motion free condition has higher resonance frequency when it is compared with that of motion fixed. The installation of cofferdam moves resonance frequency to higher region and also generates secondary resonance at lower frequency. Furthermore, it was found that cofferdam was the cause of generating waves in the longitudinal direction when the vessel was in beam sea.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.204-209
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• 2004

Recently, the various performances of vehicle are rapidly improved. Therefore tire noise is recognized as important noise source because vehicle noise is considerably reduced. This study is performed for the control of the cavity resonance noise that is structure-borne noise, due to fluid(air)-structure interaction. For this investigation, FRF analysis has been carried out using FEM and we found an important factor affecting cavity resonance. The effect of this factor is confirmed by objective noise test. We confirmed that the result of FRF analysis and objective noise test is that the structure control of tire sidewall can reduce cavity resonance noise due to fluid-structure interaction

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 추계학술대회논문집
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• pp.596-599
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• 2008

Traditionally, tire made a role of function, which is supporting vehicle load, making brake, transferring traction, etc. But tire is a part of vehicle design, nowadays. In accordance with this market trend, customers need a wide tread design tire (i.e. low series tire). Generally low Series Tire means stiffer than general tire. That brings out increasing road noise. (Especially tire cavity resonance noise) Tire noise is divided in structure home noise and air borne noise. Tire cavity resonance noise (structure home noise) come from vibration between tire and vehicle. In the study, we investigated that tire cavity resonance noise is affected by stiffness of tread and sidewall.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집 특별세미나,특별/일반세션
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• pp.457-462
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• 2009

In a high speed train, aluminium extruded panel is widely used in floor, side wall and roof structures for high bending stiffness and weight reduction. However, with some inevitable reasons, aluminium extruded panel shows inferior sound insulation performance compared with the flat panel having same weight. Especially, occurrence of local resonance modes in the particular frequency band, is one of the main reason in the deterioration of the sound insulation performance. Local resonance modes are generated in the structure which consists of periodic unit structure, such as the aluminium extruded panel. The local resonance frequency is determined by the specification of the unit structure. In this study, we predict the local resonance frequency band on the aluminium extruded panel used for the high speed train, and investigate how the design modification in the unit structure influences the local resonance frequency band and panel bending stiffness. The purpose of the study is to provide the design information for the effective unit structure in order to improve the sound insulation performance of the aluminium extruded panel.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 추계학술대회 논문집
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• pp.309-313
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• 2009

A micromechanical resonance sensor detects the resonance frequency shift due to mass or adsorption induced surface stress change during molecular adsorption or interaction on its surface. The resonance sensor is surrounded by gas or liquid solution during operation. To study the resonance shift phenomena depending on its surrounding environment, fluid-structure interaction of the resonance sensor has been analyzed for the different fluid environment and boundary conditions using finite element analysis.

• 한국자기공명학회:학술대회논문집
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• 한국자기공명학회 1999년도 하계총회 및 제15회 자기공명 학술발표회
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• pp.26-26
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• 1999

• 한국자기공명학회논문지
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• 제12권2호
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• pp.65-73
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• 2008

HP1298 (Swiss-Prot ID ; P65108) is an 72-residue protein from Helicobacter pylori strain 26695. The function of HP1298 was identified as Translation initiation factor IF-l based on sequence homology, and HP1298 is included in IF-l family. Here, we report the sequence-specific backbone resonance assignments of HP1298. About 97% of all the $^{1}HN$, $^{15}N$, $^{13}C{\alpha}$, $^{13}C{\beta}$, and $^{13}CO$ resonances could be assigned unambiguously. We could predict the secondary structure of HP1298, by analyzing the deviation of the $^{13}C{\alpha}$ and $^{13}C{\beta}$ shemical shifts from their respective random coil values. Secondary structure prediction shows that HP1298 consists of six $\beta$-strands. This study is a prerequisite for determining the solution structure of HP1298 and investigating the structure-function relationship of HP1298. Assigned chemical shift can be used for the study on interaction between HP1298 and other Helicobacter pylori proteins.

• BMB Reports
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• 제38권5호
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• pp.591-594
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• 2005

One of the small proteins from Helicobacter pylori, HP1242, was investigated by the solution nuclear magnetic resonance (NMR) spectroscopy. HP1242 is known as a 76-residue conserved hypothetical protein and its function cannot be identified based on sequence homology. Here, the results of the backbone $^1H$, $^{15}N$, and $^{13}C$ resonance assignments of the HP1242 are reported using double- and triple-resonance techniques. About 95% of all of the $^1HN$, $^{15}N$, $^{13}CO$, $^{13}C{\alpha}$, and $^{13}C{\beta}$ resonances that cover 75 non- Proline residues of the 76 residues are clarified through sequential- and specific- assignments. In addition, three helical regions were clearly identified on the basis of the resonance assignments.

• 한국자기공명학회논문지
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• 제1권1호
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• pp.21-29
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• 1997

Three typical solvent suppression methods employed for measuring the NOE data that are used for structure determination of polypeptides by modeling were discussed and compared with one another. In the experiments with several peptides composed of 10 to 65 amino acids the presaturation method was found to give severely distorted signal intensities of exchangeable protons, thus making the results based on this method much less reliable.

• 항공우주기술
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• 제7권1호
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• pp.151-160
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• 2008

본 논문에서는 발사체에 적용하는 전기-유압식 추력벡터제어 구동장치시스템의 합성공진 현상에 대한 해석 연구결과를 기술한다. 합성공진 현상은 위치서보 구동장치시스템을 유연한 발사체 기체구조체 지지부에 장착하였을 때 발생한다. 이는 관성부하를 갖는 전기-유압식 위치서보 시스템의 유압공진 현상과 유연한 기체구조체 지지부의 구조공진 현상의 합성에 의하여 발생한다. 합성공진 현상은 발사체 제어시스템에 의하여 되먹임 및 증폭되어 안정성을 악화시킬 수 있다. 이와 같은 현상을 정확하게 예측 및 분석할 수 있는 비선형 모델을 개발하였으며 이에 기반을 둔 합성공진 억제 특성이 우수한 동적 압력 되먹임(dynamic pressure feedback) 제어기법을 개발하였다.