• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.867-870
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• 2002

In high-speed optical disk drive, the excitation caused by rotation of a mass-unbalanced disk is a major source of vibration. The vibration can be a disturbance to the servo system, which is sufficient to cause severe failures in the reading and writing process. The vibration also causes users to feel unpleasantness. The vibration reduction is therefore essential for the reliable operation of optical disk drive. One of the approaches to reduce the vibration is a dynamic vibration absorber (DVA). In this paper, we analyze the dynamic behavior of $DVD\pmRW$ combo drive system with DVA through 12_dof rigid multi-body dynamic model. The effective location and the optimal frequency ratio are obtained from the analysis.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2005년도 동계학술발표대회 논문집
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• pp.506-510
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• 2005

This study shows work on the properties of noise and vibration in Whirlpool bath and plan for its reduction. Totally through 3 steps. we found out the properties of noise and vibration. various anti-vibration design for an effeciency test is conducted. By Anti-vibration for the pump causing vibration, about 4dB(A) was reduced. Moreover. by anti-vibration construction fixing the bathtub frame. about 3db(A) could be reduced. In the case of anti-vibration construction about the wall around the bathtub. and spreading damping paint on the bathtub. the noise was reduced.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 추계학술대회 논문집
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• pp.185-189
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• 2009

It is very important to control the vibration transmitted from external utilities and the transient response due to the internal sources for the precision equipment, which is very sensitive to the vibration environment. The anti-vibration tables that use air springs have been widely used due to their excellent isolation performance, but the systems with high flexibility have the critical problem of large transient response by the impulsive force of the moving mass in operation of the equipment. In this paper, the hybrid vibration control system is proposed, which is combined the air springs with the semi-active MR dampers in order to satisfy the performances of isolation and vibration reduction simutaneously.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.660-664
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• 2014

A diesel forklift truck under 3-ton class has disadvantages in the vibration transmission path. Because the weight ratio of body structure to powertrain which is source of excitation force is lower th an a mid-class forklift. In addition, the torsional and bending vibration mode frequencies of body structure are within the engine excitation frequency range, then high idle vibration generated by resonance. In this paper vehicle body structure design and optimization technique considering idle vibration reduction are presented. Design sensitivity analysis is applied to search the sensitive of design parameters in body structure. The design parameters such as thickness and pillar cross section were optimized to increase the torsional and bending vibration mode frequencies.

• 우주기술과 응용
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• 제2권3호
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• pp.187-194
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• 2022

안테나의 고속 정밀 지향성 확보를 위해 동작되는 모터의 구동에 의한 외란의 크기는 극히 미소함에도 불구하고, 정밀 지향 성능이 요구되는 관측 위성의 영상 품질을 저해하는 주요 원인으로 작용하게 된다. 고해상도 관측위성의 지향 성능 향상을 통한 고해상도 영상정보 획득을 위해서는 지향성 안테나의 모터 구동시 발생하는 미소진동(Jitter)이 주요 임무 장비에 전달되지 않도록 적절한 진동절연 및 저감 설계가 요구된다. 본 논문에서는 실제 위성에 적용된 지향성 안테나 진동저감 장치에 대해 개발과정과 적용 전후의 미소 진동 저감 효과에 대해 살펴보고자 한다. 이 장치는 별다른 인터페이스 추가 장비 없이, 지향성 안테나 구동부 내에 있는 기어 하나만을 스프링 댐퍼 기어 형태로 교체함으로서, 발생되는 지터문제를 획기적으로 개선할 수 있는 방법으로 고안되었으며, 이 방식은 2015년에 발사된 서브미터급 고해상도 지구관측 위성에 처음으로 적용되어 발사되었으며, 현재까지 성공적으로 운용 중에 있다.

• 한국생산제조학회지
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• 제8권6호
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• pp.119-125
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• 1999

This article proposes the analytical and experimental approaches for the reduction of vibration generated in the gear box of an NC machine. The lateral critical speed of main spindle and torsional natural frequencies were analyzed and the impact testing of gear box was performed. These results were compared with the forced operating speeds, The vibration was much diminished by redesign of gear module and reinforcement of box structure.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.1019-1023
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• 2006

Conventional methods for reducing vibration in engineering designs may be undesirable in conditions where size or weight must be minimized, or where complex vibration spectra exist. Fe-Mn Damping alloy with a combination of high damping capacity and good mechanical properties can provide attractive technical and economical solutions to problems involving seismic, shock and vibration isolation. We have studied the noise and vibration characteristic of Dampalloy and checked Dampalloy reduced noise about 3.9dB and vibration about 15.9 times as compared conventional material through laboratory research. With this result, we obtained a good possibility of material substitution about the bridge expansion joint

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2004년도 가을 학술발표회 논문집
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• pp.68-75
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• 2004

In this paper a study on the reduction method of ground vibration by a french is carried out. The transmitted load into the ground which induces the ground vibration is computed through a study on the interaction between tilting car and the line. This load is applied into the numerical model which is one for a study on the reduction method of ground vibration by a trench. Then the numerical results is compared with the experimental results conducted in the previous study.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2010년도 추계학술대회 논문집
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• pp.354-355
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• 2010

• 한국소음진동공학회논문집
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• 제22권1호
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• pp.46-52
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• 2012

Since the engine and reduction gear in a naval vessel are usually supported by the mounting system separately, the misalignment between the input shaft of the reduction gear and the output shaft of the engine should occur caused by ship motion. In this study, this misalignment is estimated from the linear static analysis assuming that the phase of movements of the engine and reduction gear at low frequency range is same and the dynamic effect is not affect to them. Through comparing the relative displacement of the engine and reduction gear calculated from linear static analysis to that from dynamic analysis as well as experiment, the assumption in this study could be verified.