• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.301-305
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• 2002

Among many structural dynamics modification methods for plate and shell vibration problems, embedding an emboss to the surface is very efficient. But deciding an optimal position and shape using optimization algorithm needs defining geometry and remeshing the model for every iteration step to implement the method, which takes much numerical cost. An equivalent element produced here lessen the cost by representing the geometrical characteristics of an emboss using the element's material properties and thickness becoming a geometrically homogenous element of the base plate or shell. Some efficient factors which let the equivalent system have the same dynamical response as the original system embedded with emboss will be shown and the degree of equivalence will be tested in terms of natural frequency matching.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1994.10a
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• pp.107-117
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• 1994

A design methodology is applied for manufacturing a disk-brake piston component and a washing machine container. The design criteria are the limit drawing ratio and the forging load within the available press limit. Also, the final product should not have any geometrical defect. The rigid-plastic and elastic-plastic FEM have been applied to simulate both of the conventional manufacturing processes, respectively, which include deep drawing and forging process. Simulations of one stage process from a selected stock to the final product shape are performed for generating information on additional requirements for metal flow. The best manufacturing processes are selected, which is using a hemispherical punch in the deep drawing process for both disk-brake piston component and washing machine container.

• Journal of Astronomy and Space Sciences
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• v.1 no.1
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• pp.67-74
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• 1984

Photoelectric UBV light curves of AR lacertae made in one season during 1981-82 are presented. Although the shape of the light curves in the outside eclipses shows a strong distortion, the scatter of observations as well as phase coverage are better than those previously available. Fourier coefficients are derived from the V-light curve and the observed curve successfully rectified to the Russell model. Light curve solutions are computed and the geometrical and physical parameters of AR Lac are derived as $a_s$=0.182, $a_g$=0.341, j=$86^{circ}$3, $L_s$=0.372, $L_g$=0.628, k=0.53, $X_s$=0.85, $X_g$=0.4.

• Journal of Biosystems Engineering
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• v.26 no.6
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• pp.495-502
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• 2001

Upright positioning of garlic cloves has been considered as an essential process for mechanical planting because positioning affects the quality and yield of garlic production. Due to the geometrical uniqueness and irregularity of garlic cloves in shape, the planting operation has been conducted by manual. Manual planting requires intensive labors and high production cost. The overall Boal of this research was to develop a garlic clove planter which maintains a garlic clone upright. Specific objective was investigating planting condition and physical properties of garlic clove. The results were summarized as fellows : Based on the survey results, a garlic clove planter should have a planting capacity of at least 140 cloves in a pyung (3.3m$^2$) with the row spacing of 140mm and hill spacing of 120mm for a productive cultivation.

• Proceedings of the Korea Contents Association Conference
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• 2006.05a
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• pp.342-346
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• 2006

The method presented is also efficient and applicable in estimating the discharge in high flows that are very difficult or impossible to measure before, due to technical or theoretical reasons. The method can drastically reduce the time and cost of measurement, regardless of the irregularity in the geometrical shape. With Microwave Water Surface Velocity Meter, An entropy based method for determining the discharge in the rivers can be used to develop real-time discharge measurement system (RDMS) which can carry out the real-time inflow hydrograph.

• Journal of the Korean Society of Safety
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• v.23 no.4
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• pp.30-35
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• 2008

The present study has been conducted to examine the effect of grid resolution on the predicted results for electric cable fire using pyrolysis model in FDS(Fire Dynamics Simulator, version 5). The grid independent test for different grid resolutions has been performed for a PE coating cable and the grid resolution is defined by the non-dimensional characteristic length of fire and mean grid size. The calculated maximum heat release rate and mean flame spread rate were almost constant for higher grid resolution of 20${\sim}$25 and the computing time for the grid resolution takes approximately 20hours to solve flame propagation with pyrolysis model. The geometrical simplification of a electric cable dose not greatly affect on the maximum heat release rate and flame spread rate and the rectangular approximation of cable shape gives acceptable result comparing with the round cable with stepwise grid.

• Proceedings of the KIEE Conference
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• 2005.05a
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• pp.60-62
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• 2005

In this study, the automatic tracking algorithm tracing a human face is proposed by using YCbCr color coordinated information and its thermal properties expressed in terms of thermal indexes in an infra-red image. The facial candidates are separately estimated in CbCr color and infra-red domain, respectively with applying the morphological image processing operations and the geometrical shape measures for fitting the elliptical features of a human face. The identification of a true face is accomplished by logical 'AND' operation between the refined image in CbCr color and infra-red domain.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2000.10a
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• pp.13-16
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• 2000

In the hot strip mill, a bad threading and shape of strip strip in the finishing mill was caused by asymmetric rolling In roughing min. Mathematical analysis for camber control of roughing mill in hot strip rolling has been developed. Each equation in the camber control model was derived from geometrical characteristics of camber mechanism. The model can predict variables such as wedge, side slippage and roll force difference etc. from a measured camber value and then find an optimum roll gap condition for minimizing camber in the next pass.

• Transactions of Materials Processing
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• v.3 no.2
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• pp.178-188
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• 1994

A design methodology is applied for manufacturing a disk-brake piston component. The design criteria are the limit drawing ratio and the forging load within the available press limit. Also, the final product should not have any geometrical defect. The rigid-plastic FEM has been applied to simulate the conventional four stage manufacturing processes, which include deep drawing and forging process. Simulation of one stage process from a selected stock to the final product shape is performed for generating information on additional requirements for metal flow. Two stage forming processes with different punch corner and nose geometries are also simulated to identify the possible best solutions. Finally, the best manufacturing process is selected, which is using a hemispherical punch int he deep drawing process.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.2048-2053
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• 2005

The aim of this paper is to compensate hysteresis phenomena in Shape Memory Alloy (SMA) actuators by using numerical inverse Preisach model. This is used to design a controller that correct hysteresis effects and improve accuracy for the displacement of SMA actuators. Firstly, hysteresis is identified by numerical Preisach model implementation. The geometrical interpretation from first order transition curves is used for hysteresis modeling. Secondly, the inverse Preisach model is formulated and incorporated in open-loop control system in order to obtain desired input-output relationship with hysteresis reducing. The experimental results for hysteresis compensation by using this method are also shown in this paper.