• 한국소음진동공학회논문집
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• 제24권9호
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• pp.695-705
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• 2014

In this paper, two types of techniques for the prediction of radiated sound pressure due to vibration of a structure are investigated. The prediction performance using wave-number sensing technique is compared to that of conventional prediction method, such as Rayleigh's integral method, for the prediction of far-field radiated sound pressure. For a coupled plate, wave-number components are predicted by the vibration response of plate and the prediction performance of far-field sound is verified. In addition, the applicability of distributed sensors that are not allowable to Rayleigh's integral method is considered and these can replace point sensors. Experimental implementation verified the prediction accuracy of far-field sound radiation by the wave-number sensing technique. Prediction results from the technique are as good as those of Rayleigh's integral method and with distributed sensors, more reduced computation time is expected. To predict the radiated sound by the efficient configuration of structural sensors, composed(synthesized) mode considering sound power contribution is determined and from this size and location of sensors are chosen. Four types of sensor configuration are suggested, simulated and compared.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 춘계학술대회 논문집
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• pp.597-602
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• 2002

This study reviews several of the procedures that have been used to predict ground-born vibration. The vibration responses are measured at three sites that have different soil qualities. The measured vibration levels are compared with the predicted results by previously used vibration level prediction models. In this study a numerical method, which is based on explicit differential method, is used to compensate tot existing prediction models. Although numerically computed results are not quantitatively in good agreement with the measured results, the trends are comparable in the sense that vibration level does not decrease monotonically with distance. Also, The site with the deepest tunnel gives the highest vibration level.

• 한국공간구조학회논문집
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• 제6권3호
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• pp.35-41
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• 2006

구조물의 모니터링과 손상 및 진동예측에 많은 센서들이 사용되고 있으며, 압전소자 및 변형게이지는 재료 및 구조물의 손상에 사용되고 있다. 그러나 진동에 대한 실험은 미진한 실정이다. 압전소자는 구조물의 변형되었을 때 로드셀의 경우에서처럼 작용되는 외력을 전기적인 신호로 바꾸어주는 센서이다. 이를 이용하여, 철근 콘크리트 판에서 진동예측을 압전소자의 전압변화로 사용하였다. 본 연구는 판에서 압전소자를 사용하여 진동을 예측하기 위한 기초적 연구이다.

• Geomechanics and Engineering
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• 제30권3호
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• pp.273-280
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• 2022

A certain amount of random vibration excitation to subway track is caused by subway operation. This excitation is transmitted through track foundation, tunnel, soil medium, and ground building to the ground and ground structure, causing vibration. The vibration affects ground building. In this study, the results of ANSYS numerical simulation was used to establish back-propagation (BP) neural network model. Moreover, a back-propagation neural network model consisting of five input neurons, one hidden layer, 11 hidden-layer neurons, and three output neurons was used to analyze and calculate the vertical Z-vibration level of New Capital's ground buildings of Qingdao Metro phase I Project (Line M3). The Z-vibration level under different working conditions was calculated from monolithic roadbed, steel-spring floating slab roadbed, and rubber-pad floating slab roadbed under the working condition of center point of 0-100 m. The steel-spring floating slab roadbed was used in the New Capital area to monitor the subway operation vibration in this area. Comparing the monitoring and prediction results, it was found that the prediction results have a good linear relationship with lower error. The research results have good reference and guiding significance for predicting vibration caused by subway operation.

• 한국소음진동공학회논문집
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• 제16권3호
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• pp.270-282
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• 2006

In general, the vertical vibration problems for strength of members and serviceability of building structures are not considered in structural design process, but the prediction of the vertical vibration is very important and essential to structural design process. This study aims to investigate the characteristics of vertical vibration in terms of the transfer of horizontal directions to near-rooms on the shear wall building structures. In order to examine the characteristics of vertical vibration, the modal test and the impact (heel-drop and hammer) excitation experiments were conducted several times on two building structure. The results from the experiments are analyzed and compared with the results. The results of this study suggest that the characteristics of vertical vibration transfer in horizontal way are effected from the fundamental frequency of the slabs, and are effected the shear wall on the Path of the vibration transfer.

• 소음진동
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• 제2권4호
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• pp.273-280
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• 1992

The prediction of vibration response of floor is necessary in order to check whether the floor vibration level will satisfy the allowable vibration standard of precise machinery such as electronic microscopes in semiconductor manufacturing plant before the installation of various neighboring equipment facility. In conventional vibration isolation, we were mainly interested in minimization of vibration transmissibility and stabilization of vibration isolation system. But in order to predict vibration response of floor, it is necessary to know exciting force of equipment installed on the floor and the mobility of the floor. We measured the exciting force of the dropped mass assumed as equipment and the mobility of some practical building floor using large impact hammer. And from this we predicted the vibration response of floor on which the mass dropped. This predicted vibration response of floor is compared with measured vibration response. Through upper procedure, we examined the possibility of predicting vibration response of floor from the information of exciting force of equipment and the mobility of floor.

• 한국소음진동공학회논문집
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• 제22권2호
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• pp.123-129
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• 2012

It was previously suggested the design sensitivity analysis based on transmissibility function to identify the most sensitive response location over a small design modification. On the other hand, energy isoclines were used to predict the fatigue damage with acceleration response only. Both of previous studies commonly tackle the engineering problem using the acceleration response alone such that it may be possible to investigate the relationship between sensitivity analysis and accumulated fatigue damage. In this paper, it is suggested the novel method of vibration fatigue prediction using design sensitivity analysis to enhance the accuracy of predicted accumulated fatigue. Uni-axial vibration testing is performed with a simple notched specimen and the prediction of fatigue damage is conducted using accelerations measured at different locations. It can be concluded that the accuracy of predicted fatigue damage is proportional to the sensitivity index of the responsible location.

• 화약ㆍ발파
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• 제29권2호
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• pp.32-42
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• 2011

발파진동의 해석영역은 크게 두 가지 영역으로 구분될 수 있다. 첫째는, 대상 지장물에 대한 영향을 평가할 목적으로 시행되는 원거리 진동분석과, 둘째는, 암반의 손상 및 근거리 지중 구조물에 대한 영향을 평가할 목적으로 시행되는 근거리 지중진동 분석이 있다. 전자의 분석방법은 현재 국내외에서 보편적으로 활용되는 방법이며, 후자의 경우는 대체적으로 Holmberg모델을 사용하여 분석이 이루어져 왔고, 이 모델에 의해 제안된 방법은 기본적인 자료를 원거리 지표 진동 측정 데이터를 활용하는 방법을 근간으로 하여 분석이 이루어진다. 그러나, 최근 십수년동안 수행된 근거리 지중진동 실계측 결과에 따르면 Holmberg모델의 보완에 대한 필요성이 대두되었으며, 국내에서도 처음 시도되어 그 방향성을 제시하고자 하였으나 계측하는 방법에만 한정되었을 뿐 적정한 해석 모델 및 예측방법을 제시하지는 못했다. 따라서, 본 연구에서는 근거리 지중진동의 실계측을 통해 그 결과를 근간으로 하여 적정한 해석모델 및 예측방법을 제시하고자 하였다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 춘계학술대회 논문집
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• pp.623-624
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• 2014

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 춘계학술대회논문집
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• pp.949-954
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• 2000

In terms of vibration damage and the serviceability for occupants in buildings, the purpose of vibration study lies in the reduction of vibration damage. However, only when vibration level of buildings is available, measures of vibration control and base isolation can be taken. The purpose of this paper is to provide a fundamental analysis method to estimate structural vibration. After analysing by using two methods, infinite model, combination method, a comparison between analysed results and the results of previous studies was performed to prove the validity of the prediction on the vibration of building structure. Thus, if the material property of soil and quantity of load sources are known before construction being started, the vibration level could be predicted by using these methods.