http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Jeong, Darae,Choi, Yongho,Kim, Junseok Elsevier 2018 Communications in nonlinear science & numerical si Vol.62 No.-
<P><B>Abstract</B></P> <P>We present a simple mathematical model and numerical simulations of the hexagonal pattern formation of a honeycomb using the immersed boundary method. In our model, we assume that the cells have a circular shape at their inception and that there is a force acting upon the entire circumference of the cell. The net force from the individual cells is a key factor in their transformation from a circular shape to a rounded hexagonal shape. Numerical experiments using the proposed mathematical model confirm the hexagonal patterns observed in honeybee colonies.</P> <P><B>Highlights</B></P> <P> <UL> <LI> We present a simple mathematical model of the hexagonal pattern formation. </LI> <LI> To validate the proposed model, we compared simulated and experimental results. </LI> <LI> The proposed model captures the main transformation mechanism of honeycomb. </LI> </UL> </P>
BINARY IMAGE INPAINTING USING THE ALLEN-CAHN EQUATION
Darae Jeong,Junseok Kim 한국산업응용수학회 2009 한국산업응용수학회 학술대회 논문집 Vol.4 No.2
Image inpainting is the process of reconstructing lost or deteriorated parts of images using information from surrounding areas. In this paper, we present an unconditionally stable hybrid numerical method for solving one model based on Allen-Cahn equation for image inpainting. The proposed method is based on operator splitting techniques. We split this model into three terms, i.e., first-order linear equation, heat equation, and second-order nonlinear equation. We describe the numerical solution algorithm and prove the unconditional stability of the proposed scheme. We present numerical experiments to demonstrate the accuracy and efficiency of the proposed method.
INPAINTING OF BINARY IMAGES USING A PHASE-FIELDMODEL
Darae Jeong,Li YiBAO,Hyun Geun Lee,Junseok Kim 한국산업응용수학회 2009 한국산업응용수학회 학술대회 논문집 Vol.2009 No.5
Image inpainting is the filling in missing or damaged regions of images using information from surrounding areas. We compared our new modified CH equation with the modified CH eq. in previous paper [1] and developed on automatic varying ? and adaptive time step.
FAST AND AUTOMATIC INPAINTING OF BINARY IMAGES USING A PHASE-FIELD MODEL
DARAE JEONG,YIBAO LI,HYUN GEUN LEE,JUNSEOK KIM 한국산업응용수학회 2009 Journal of the Korean Society for Industrial and A Vol.13 No.3
Image inpainting is the process of reconstructing lost or deteriorated parts of images using information from surrounding areas. We propose a computationally efficient and fast phase-field method which uses automatic switching parameter, adaptive time step, and automatic stopping of calculation. The algorithm is based on an energy functional. We demonstrate the performance of our new method and compare it with a previous method.
Darae Jeong,In-Suk Wee,Junseok Kim 한국산업응용수학회 2011 한국산업응용수학회 학술대회 논문집 Vol.6 No.1
This paper presents an accurate and efficient numerical method for solving the Black-Scholes equation. The method uses an adaptive grid technique which is based on a far-field boundary position of the equation and also the Peclet condition. For a given error tolerance, we determine a priori a suitable far-field boundary location and then put a uniform fine grid around the non-smooth points and a non-uniform grid in the remaining regions. Numerical tests are presented to demonstrate the accuracy and efficiency of the proposed method. The results show that the computational times using this new adaptive grid method are reduced substantially when compared to those of a uniform grid method with a similar magnitude of error.
Jeong, Darae,Ha, Taeyoung,Kim, Myoungnyoun,Shin, Jaemin,Yoon, In-Han,Kim, Junseok Korean Mathematical Society 2014 대한수학회보 Vol.51 No.4
We present an accurate and efficient numerical method for solving the Black-Scholes equation. The method uses an adaptive grid technique which is based on a far-field boundary position and the Peclet condition. We present the algorithm for the automatic adaptive grid generation: First, we determine a priori suitable far-field boundary location using the mathematical model parameters. Second, generate the uniform fine grid around the non-smooth point of the payoff and a non-uniform grid in the remaining regions. Numerical tests are presented to demonstrate the accuracy and efficiency of the proposed method. The results show that the computational time is reduced substantially with the accuracy being maintained.
A NUMERICAL METHOD FOR THE PHASE-FIELD MODEL OF THE VESICLE DYNAMICS
Darae Jeong,Yibao Li,Junseok Kim 한국산업응용수학회 2013 한국산업응용수학회 학술대회 논문집 Vol.8 No.1
In this paper, we propose an accurate and robust numerical method for the phase-field model of the Willmore flow with area conservation and interface length constraint in two-dimensional space. Our method is similar to the one used by Du et al. [A phase field approach in the numerical study of the elastic bending energy for vesicle membranes, J. Comput. Phys. 198 (2004) 450?468] with a key difference. Here, we use a space-time dependent Lagrange multiplier to accurately conserve the area of vesicle membranes while Du et al. introduced a penalty term to roughly enforce the area conservation. We also derive the phase-field model for the Willmore functional using a simple argument. The proposed numerical method is based on an unconditionally gradient stable scheme and a direct area correction algorithm. The accuracy and effectiveness of the proposed model and numerical algorithm are demonstrated through numerical examples.
AN ADAPTIVE MULTIGRID TECHNIQUE FOR OPTION PRICING UNDER THE BLACK–SCHOLES MODEL
DARAE JEONG,YIBAO LI,YONGHO CHOI,KYOUNG-SOOK MOON,JUNSEOK KIM 한국산업응용수학회 2013 Journal of the Korean Society for Industrial and A Vol.17 No.4
In this paper, we consider the adaptive multigrid method for solving the Black?Scholes equation to improve the efficiency of the option pricing. Adaptive meshing is generally regarded as an indispensable tool because of reduction of the computational costs. The Black?Scholes equation is discretized using a Crank?Nicolson scheme on block-structured adaptively refined rectangular meshes. And the resulting discrete equations are solved by a fast solver such as a multigrid method. Numerical simulations are performed to confirm the efficiency of the adaptive multigrid technique. In particular, through the comparison of computational results on adaptively refined mesh and uniform mesh, we show that adaptively refined mesh solver is superior to a standard method.