• Proceedings of the Optical Society of Korea Conference
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• 1996.09a
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• pp.24-24
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• 1996

• Computational Structural Engineering
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• v.12 no.1
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• pp.71-77
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• 1999

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.633-634
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• 2010

• Transactions of the Korean Society of Mechanical Engineers A
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• v.22 no.1
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• pp.215-226
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• 1998

This paper addresses an analytical approach to tolerance and reliability analysis of mechanical systems with uncertainty. Many mechanical systems consist of links and lubricated joints. The mobility method is applied to consider lubrication effects and the clearance vector model is used to stochastically define a mechanism for tolerance and reliability analysis. To show the validity of the proposed method, a four-bar path generator and a slider-crank mechanism are considered. The results obtained by applying the proposed method are compared with those by Monte-Carlo simulation.

• The KSFM Journal of Fluid Machinery
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• v.2 no.3 s.4
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• pp.30-36
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• 1999

Blade shape profile in the axial compressor is one of the most important factors governing its aerodynamic characteristics. Manufacturing tolerance, which is inevitable in the blade manufacturing processes, may change blade profile and as a consequence, it will affect the compressor performance. In this paper, influence of manufacturing tolerance on the aerodynamic characteristics of axial compressor blades with distortion of blade profile curvatures is investigated by using a flow simulation technique. It is found that manufacturing tolerance can be an important factor affecting the source of both profile and wake losses of the axial compressor blades.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.829-832
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• 2002

With the increase of storage density, high rotational speed and high access technologies in optical disk drive, mechanical issues, mainly noise and vibration, become critical. Up to now the researches of rubber mount for anti-vibration focused on how to calculate the static and the dynamic stiffness of rubber mount and leaved out of consideration of the dimensional tolerance of rubber mount for anti-vibration. This paper presents the effects of dimensional tolerance of rubber mount for anti-vibration on the dynamic characteristics of optical disk drive by finite element analysis and dynamic test. The relation between dimensional tolerance and dynamic characteristics of optical disk drive is observed and discussed.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.11a
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• pp.95-100
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• 2006

Tolerance analysis method for natural frequencies of multi-body systems having a equilibrium position is suggested in this paper. To perform the tolerance analysis, the Monte-Carlo Method is conventionally employed. However, the Monte-Carlo Method has some weakness; spending too much time for analysis and having a low accuracy and hard to converge in the numerical unstable area. To resolve these problems, a tolerance analysis method is suggested in this paper. Sensitivity equations of natural frequencies are derived at the equilibrium position. By employing the sensitivity information of mass, damping and stiffness matrices, the sensitivity of natural frequencies can be calculated.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.7
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• pp.549-555
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• 2008

Analytical method to analyze the tolerance effect on the vehicle ride comfort is suggested in this paper. Ride comfort is one of the most important performance indices which decide the vehicle design quality. In general, the ride comfort is affected by the variations of parameters of a vehicle model. Therefore, the effects of the parameters on the ride comfort need to be evaluated statistically based on the whole-body vibration of the vehicle. In this paper, weighted RMS values of the acceleration PSD of a seat position are used to define the ride comfort. The equations of motion and the sensitivity equations are derived based on a 5-DOF vehicle model. By employing the sensitivity information of the acceleration at the seat position, the tolerance effect on the vehicle ride comfort could be effectively analyzed.

• Proceedings of the Safety Management and Science Conference
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• 2006.04a
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• pp.115-121
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• 2006

SCM 경쟁력 재고는 기업 내의 부문별 또는 개별기업 내부의 한정된 개선 노력이 외부의 부문 또는 기업에서의 활동과 연계되어 전체의 최적화가 되지 않으면 그 성과가 극히 제한적일 수 밖에 없다. 따라서 히든 코스트(hidden cost)의 발견 및 유통물류의 최적화에 박차를 가하는 것이 현실이다. 본 연구는 순 물류로 진행한 유통 경로 상에서 만약 역 물류가 발생할 경우 순물류 비용이외 공차(empty driving)로 인한 역물류의 히든 코스트를 최소화하는 모형을 통해 물류이익을 최대화 할 수 있는 방안을 찾기 위해 노력하며 결국 순물류와 역물류상의 유통상의 비용과 이익의 쌍대성에 기초하여 Pull, Push 시스템을 이용한 최적 시스템 모델화를 수행하여 효율적인 물류비용 산정의 방법을 모색한다.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.17 no.7 s.124
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• pp.579-586
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• 2007

Analytical method to analyze the effect of tolerance on the modal characteristic of multi-body systems in dynamic equilibrium position is suggested in this paper. Monte-Carlo method is conventionally employed to perform the tolerance analysis. However, Monte-Carlo method spends too much time for analysis and has a greater or less accuracy depending on sample condition. To resolve these problems, an analytical method is suggested in this paper. Sensitivity equations for damped natural frequencies and the transfer function are derived at the dynamic equilibrium position. By employing the sensitivity information of mass, damping and stiffness matrices, the sensitivities of damped natural frequencies and the transfer function can be calculated.