• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 추계학술대회논문집
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• pp.1313-1317
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• 2007

Manufacturing condition is one of the most important factors in precision manufacturing. In this study, we optimized minimizing the Z vibration acceleration using RSM(response surface methodology) by table of orthogonal array. RSM was well adapted to make the analytical model of the minimum vibration acceleration and enable the objective function to be easily created and a great deal of the time in computation to be saved. Therefore, it is expected that the proposed optimization procedure using RSM can be easily utilized to solve the optimization problem of manufacture condition.

• 한국소음진동공학회논문집
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• 제12권10호
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• pp.785-791
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• 2002

A modeling method for the dynamic characteristic analysis of a translationally accelerated trapezoidal cantilever plate is presented in this paper. The equations of motion for the plate are derived and transformed into a dimensionless form. The effects of the inclination angles and the acceleration on the vibration characteristics of the plate are investigated. Incidentally, natural frequency loci veering and associated mode shape variations are observed and discussed.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 추계학술대회논문집
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• pp.1028-1033
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• 2002

This paper concerns on a non-rotating axis-active magnetic bearing (AMB) system subject to base motion. In such a system, it is desirable to retain the axis within the predetermined air-gap. Motivated from this, an optimal acceleration feedforward control is proposed to reduce the base motion response without deteriorating other feedback control performances. Experimental results demonstrate that the proposed feedforward control reduces the air-gap deviation to 29% that by feedback control alone.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 D
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• pp.1858-1859
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• 2006

This paper presents a new fuzzy-neural-network based interacting multiple model (FNNBIMM) algorithm for tracking a maneuvering target. To effectively handle the unknown target acceleration, this paper regards it as additional noise, time-varying variance to target model. Each sub model characterized by the variance of the overall process noise, which is obtained on the basis of each acceleration interval. Since it is hard to approximate this time-varying variance adaptively owing to the unknown acceleration, the FNN is utilized to precisely approximate this time-varying variance. The gradient descendant method is utilized to optimize each FNN. To show the feasibility of the proposed algorithm, a numerical example is provided.

• 한국소음진동공학회논문집
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• 제15권7호
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• pp.806-812
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• 2005

This paper adresses the shaking table tests with 1/100 scaled model followed similitude law for OOdam main designing section to understand nonlinear behavior characteristics of concrete dam body by ground motion. As earthquake wave, Hachinohe and El Centre waves were used and acceleration and displacements are measured to analyze behaviors of dam body. For maximum ground acceleration range $(0.3\~0.9 g)$, the results showed linear behavior regardless of maximum 9round acceleration and secured safety of structure. To analyze the behavior of dam after tension cracking, 3 cm-notch was placed at the critical section of over-flowing section. As results of applying Hachinohe wave(0.8 g), Even though tension cracks were formed at over-flowing section by Hachinohe wave(0.8 g), it showed that the dam is stable for supporting upper stream Part of water tank of dam.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2012년도 춘계학술대회 논문집
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• pp.875-880
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• 2012

According to the fixation detailed drawing and lightweight anger tendency of the product the vibration control of precision equipments is essential and establishes under the equipments. so It is important to know vibration characteristics of vibration isolator. For this reason the accelerometer attaches in vibration isolator and measures an acceleration response. The acceleration response which is measured will lead double integral and will be able to predict a displacement of vibration isolator. However, in compliance with the effect of the accelerometer can not be accurately. From this paper, mass, damping ratio and natural frequency of the accelerometers by changing the vibration isolator to predict the acceleration response and the results were compared.

• 제어로봇시스템학회논문지
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• 제15권1호
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• pp.31-36
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• 2009

This paper presents a novel scalar adaptive filter, which is reformulated by additional acceleration term. The filter continuously estimates three different kinds of covariance such as the measurement noise covariance, the velocity error covariance and the acceleration error covariance. For estimating three covariances, we use the innovation method for the measurement noise covariance and the least square method for other covariances. In order to verify the proposed filter performance compared with the conventional scalar adaptive filter, we make indoor experimental environment similar to outdoor test using the ultrasonic sensors instead of GPS. Experimental results show that the proposed filter has better position accuracy than the traditional scalar adaptive filter.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 추계학술대회논문집
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• pp.614-618
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• 2003

This paper presents a system identification (SI) scheme in time domain using measured acceleration data. The error function is defined as the time integral of the least square errors between the measured acceleration and the calculated acceleration by a mathmatical model. Damping parameters as well as stiffness properties of a structure are considered as system parameters. The structural damping is modeled by the Rayleigh damping. A new regularization function defined by the L$_1$-norm of the first derivative of system parameters with respect to time is proposed to alleviate the ill-posed characteristics of inverse problems and to accommodate discontinuities of system parameters in time. The time window concept is proposed to trace variation of system parameters in time.

• 한국소음진동공학회논문집
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• 제21권2호
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• pp.112-119
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• 2011

This paper is concerned with the measurement of static and dynamic displacement by image processing(IP) and study for prediction method of velocity and acceleration. To measure the displacement visually, the measurement system consists of a telephoto zoom camera, CCD(charge coupled device) image device and a computer. The specific target on the white board is used to calculate the displacement of the structure. The captured image is then converted into a pixel-based data and then analyzed numerically. The limitation of the system depends on the image capturing speed and the pixel-size of image. In this paper, we developed for the displacement measurement using the image processing method. The proposed method enables us to measure the vibration displacement, velocity and acceleration directly without any contact. The current resolution for the displacement measurement can be seen from the results.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 추계학술대회논문집
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• pp.1043-1047
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• 2003

Most of the measurement and the evaluation of hand-transmitted vibration have been performed by using a small size single axis accelerometer between the handle and the hand palm or a three axis accelerometer attached on an adapter outside the hand(indirect measurement). It is most desirable for the correct evaluation of hand-transmitted vibration form the power tool handle to measure the acceleration between the handle surface and the hand palm in the three axis(direct measurement) as recommended in ISO 5349-1. In the study three axes acceleration measurement device was developed of which the thickness was less than 7mm so that it can be placed between the handle and the palm without any inconvenience during the measurement. To verify the performance of the developed device, measured acceleration by the two methods, direct and indirect, were compared in the study.