• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11a
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• pp.19-36
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• 2001

지난 '91년부터 2000년까지 환경분쟁조정위원회에 접수된 분쟁사례 가운데 소음ㆍ진동분야가 78％를 차지하였으며, 특히 2000년도에는 85％에 달하여 소음ㆍ진동문제가 심각해져 가고 있다. 소음ㆍ진동규제법은 '90. 8. 1 환경보전법에서 분리되어 개별법으로 정비되었으며, 소음ㆍ진동 발생원별로 합리적인 관리와 규제를 함으로써 모든 국민들이 정온한 환경에서 생활하게 하려는 취지아래 제정되었다. (중략)

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.928-933
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• 2007

In this research, we investigated active vibration control based on wave-viewpoint using the longitudinal wave separation method. The control strategy is the one of active vibration control technique for generating vibration reduced zone and uses wave information including the directivity as the cost function. In order to get the wave information from the measured values, we proposed and examined the time-domain longitudinal wave separation method proper to real time application like active vibration control. Using the proposed method, we examine the performance and feasibility of active vibration control based wave view-point through the simulation. The related experimental verification and application is going to be expected in a near future.

• The Journal of the Acoustical Society of Korea
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• v.12 no.2
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• pp.28-36
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• 1993

임의의 형상을 갖는 진동체에 의한 방사 음장해석은 경계요소법에 의하여 이미 많은 해석이 시도되었다. 그러나, 진동체의 형상이 매우 복잡한 경우에는 겉표면의 요소수가 크게 증가할 뿐만 아니라 각 요소에서의 경계조건을 모두 알아내어야 하므로, 저주파에 국한된 해석일지라도 엄청난 시간과 노력이 필요하게 된다. 이러한 어려움을 극복하기 위하여 경계요소법을 사용하되, 복잡한 형상의 진동체를 둘러싸는 가상적인 표면을 매우 간단하게 설정한 후 그 표면상의 경계조건인 음압을 측정한다. 임의의 형상에 대한 파수 영역에서의 감쇠파의여파작업을 위하여 특이값 분리를 사용하였다. 특이값 분리에 의하여 음압분포를 측정위치에서 설정된 일반 좌표계에서의 고유모드로 분해한다. 각 고유모드의 원거리 음장의 기여도에 해당하는 각 특이벡터에 대한 특이값의 크기를 비교하여, 유한개의 고유모드만을 포함시킴으로써 원거리 음장을 예측한다. 몇 개의 예제를 통하여 해석적 방법의 기존의 경계요소법에 의한 결과를 본 연구 방법의 결과와 비교하여 잘 일치함을 확인하였다.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.12
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• pp.1004-1011
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• 2018

Recently, pyrotechnic separation nut has attracted a considerable attention because of its shock reduction effect among various pyrotechnic mechanical devices. However, its bolt loosening behavior under transverse vibration has not been studied sufficiently, since segmented nuts are utilized instead of conventional nut in pyrotechnic separation nut. With the background, bolt loosening analyses are carried out referring to Junker vibration test. The analysis procedure consists of two steps. The first step is the bolt fastening step, screwing the bolt by fastening torque. The second step is the bolt loosening step under transverse vibration. Through the procedure, bolt loosening behaviors are obtained, and the effect of clearance on loosening behavior is closely investigated for reliable design of pyrotechnic separation nut.

• Journal of Navigation and Port Research
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• v.33 no.1
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• pp.57-63
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• 2009

In order to effectively isolate the marine wastes with an effluent standard, the pretreatment process is required to isolate solid materials from the liquid-solid mixed wastes. The more effective the pretreatment becomes, the more processing capacity of posttreatment will be improved and process facilities will be downsized. In this paper, we suggested the vibrating reverse-slant screen, investigated the optimal vibration frequency and vibrator installation angle for the separation of the liquid solid mixed wastes. Several experiments for separation efficiency were conducted under the condition of various vibration frequency($35{\sim}60Hz$, 5Hz interval) and vibrator angle($0^{\circ}$, $30^{\circ}$, $45^{\circ}$, $90^{\circ}$) considering the crack of screen. The screen inclination angle is set up the gradient as $3^{\circ}{\sim}5^{\circ}$ through the preliminary experiments. Also, we made two types of screen(respectively rectangle and square screen). The separation device has shown the optimum efficiency at vibrator angle $0^{\circ}$ and vibration frequency 60Hz, and has no relation with the shape of screen. And the proposed technology is verified by comparing with quantity of suspended solids before and after filtration.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.11a
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• pp.190-191
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• 2008

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.3
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• pp.111-118
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• 2003

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.04a
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• pp.520-521
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• 2013

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.04a
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• pp.803-804
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• 2013

• Journal of KSNVE
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• v.27 no.1
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• pp.7-11
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• 2017