• Geomechanics and Engineering
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• v.5 no.3
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• pp.223-240
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• 2013

In the present study an attempt was made to predict the complex nonlinear parameters of the soil-pile system subjected to the vertical vibration of rotating machines. A three dimensional (3D) finite element (FE) model was developed to predict the nonlinear dynamic response of full-scale pile foundation in a layered soil medium using ABAQUS/CAE. The frequency amplitude responses for different eccentric moments obtained from the FE analysis were compared with the vertical vibration test results of the full-scale single pile. It was found that the predicted resonant frequency and amplitude of pile obtained from 3D FE analysis were within a reasonable range of the vertical vibration test results. The variation of the soil-pile separation lengths were determined using FE analysis for different eccentric moments. The Novak's continuum approach was also used to predict the nonlinear behaviour of soil-pile system. The continuum approach was found to be useful for the prediction of the nonlinear frequency-amplitude response of full-scale pile after introducing the proper boundary zone parameters and soil-pile separation lengths.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2003.04a
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• pp.272-277
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• 2003

In order to predict vibration during end-milling process, the cutting dynamics was modelled by using neural network and combined with structural dynamics by considering dynamic cutting states. Specific cutting constants of the cutting dynamics model were obtained by averaging cutting forces and tool diameter, cutting speed, feed, axial depth radial depth were considered as machining factors. Cutting farces by test and by neural network simulation were compared and the vibration during end-milling was simulated.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11a
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• pp.352.2-352
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• 2002

In this paper, Power Flow Analysis (PFA) method has been applied to the prediction of vibration energy density and intensity of coupled shell structures in the medium-to-high frequency ranges. To consider the wave transformation at joint between shell elements, power transmission and reflection coefficients are investigated for various joint angles, and here Donnell-Mushtari thin shell theory has been used. (omitted)

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.348-357
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• 2006

Ground Vibration Tests (GVT) are needed on au new aircraft types and as part of certification. Its first objective is to verify models used for the calculation and prediction of the dynamic behavior of the structure. The main objectives of this paper are to introduce 'the integrated approach of dynamic testing for aerospace structure' in detail and 'The research projects in which LMS participated in aerospace structural dynamic area'

• Tunnel and Underground Space
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• v.4 no.2
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• pp.77-86
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• 1994

The vibration resulting from track-train interaction is transmitted through the tunnel structure and the surrounding ground to adjacent buildings. This paper provides a review of the ground vibration propagation mechanism and the theoretical isolation effectiveness of each transit systems. Moreover, predictive vibration values estimated from various models are compared with measured results performed in Seoul Metropolitan Subways and evaluate the applicability of those models.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1997.10a
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• pp.308-313
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• 1997

PC용 VMS의 한계점을 극복하기 위해 UNIX-ARC/INFO를 사용하여 WORKSTATION에서 구동되는 UNIX용 VMS를 개발하였다. 본 논문에서는 개발된 VMS의 적용가능성을 판단하기 위해 서울시를 대상으로 VMS시스템을 구현하였으며, 일부지역에서는 지하철운행시의 지반진동전파 예측을 하여 실측치와 비교를 통해 그 사용성을 평가하였다.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.6
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• pp.555-561
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• 2010

Predicted noise level has been used to assess the annoyance response since noise map was generalized and being the normal method to assess the environmental noise. Unfortunately using predicted noise level to derive the annoyance prediction curve caused some problems. The data have to be grouped manually to use the annoyance prediction curve. The aim of this paper is to propose the method to handle the predicted noise level and the survey data for annoyance prediction curve. This paper used the percentage of persons annoyed(%A) and the percentage of persons highly annoyed as the descriptor of noise annoyance in a population. The logistic regression method was used for deriving annoyance prediction curve. It is concluded that the method of dichotomizing data and logistic regression was suitable to handle the predicted noise level and survey data.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2009.04a
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• pp.302-309
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• 2009

Nowadays, the construction sites are growing in city every year, so complaints for construction noise have increased more and more. To analyze this noise scientifically, construction noise prediction program was developed in 1998 and 2005 but it is too difficult to apply program in field because there is few soundproof facilities and it can't understand the coordinate system and so on. The aim of this study is to develop noise prediction program to apply in construction sites. For this, the problems of existing program was analyzed and survey was performed to get requestion of field overseer and upgraded program. To get reliability of program, it was compared with sound measurement value in field. As a result, construction sound prediction program have various soundproof facilities data than existing program. It can also analyze multi receiver point at the same time for several construction machinery. Most of all, it is more powerful to set receiver or source in the axis of X, Y, Z. so program user can make use of it easily. An average of difference is -0.9$\sim$1.8dB.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1990.10a
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• pp.53-58
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• 1990

The use of spreadsheet packages for solving noise control problems has been cited by several authors, eg Saha[1] and Thornton[2]. The effectiveness of using spreadsheet packages compared with the traditional computer programs written in high level languages was demonstrated when applied to relatively simple problems, such as the selection of hearing protectors or the prediction of noise equation which includes logarithmic additions at most represents the physics of the problem. The simplicity of the governing equation together with the requirement to handle a vast amount of data are considered to be the major reasons for noise control engineers to use spreadsheet packages. Although shipboard noise prediction seems to be very complicated, the calculation procedure itself is, in essence, identical especially true for prediction methods based on empirical formulae[3,4], ie the procedure that consists of the three basic elements, ie source, path and receiver. This paper discusses the application of spreadsheet package LOTUS 1-2-3 to shipboard noise prediction problems. A utility program of the package is written using macro functions and is shown to be especially useful for noise control engineers who are unfamiliar with spreadsheet packages. In addition, a new type of empirical formula, to estimate structureborne noise transmission loss, is proposed.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.4
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• pp.425-432
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• 2009

Recently, reduction of road traffic noise in residential buildings has become one of the most important subjects. To reduce the road traffic noise, noise impact assessment by the road traffic prediction model is required before building construction. For reasonable road traffic noise prediction, it is required to analysis of various factors in road traffic prediction models. This paper was studied the road traffic noise propagation factors such as distance from road to building, receiver height, alignment angle of building and reflection coefficient of the building facade by two calculation models, RLS-90 and CRTN. The result showed that noise reduction was generally higher at bottom stories by ground absorption effect. The reflection coefficient of the building facade was affect of additional sound pressure level by facade reflecting. And alignment angle of building at $90^{\circ}$ was performed effective noise reduction better than $0^{\circ}$.