• Bulletin of the Korean Chemical Society
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• 제23권9호
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• pp.1267-1271
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• 2002

The conformation dependences of basis set superposition errors (BSSE) for 1,2-difluoroethane (DFE) and 1,2-dimethoxyethane (DME) molecules have been estimated using counterpoise method at the Moller-Plesset second order perturbation (MP2) level of theory with various basis sets, assuming that all BSSE dependences on conformations are due to the change in CC bond. The BSSE on the energy differences between eclipsed and gauche forms of DFE are in the range of 0.2-1.2 kcal/mol and those between local minima, gauche and anti forms, are less than 0.2 kcal/mol. For the larger DME molecule, the BSSE differences between local minima are still less than 0.4 kcal/mol, but may not be ignored compared to the energy differences of 0.2-3.0 kcal/mol between conformers.

• 대한전기학회논문지:전력기술부문A
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• 제48권9호
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• pp.1167-1174
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• 1999

In this paper, we present a new technique for the local decomposition of convex structuring elements for morphological image processing. Local decomposition of a structuring element consists of local structuring elements, in which each structuring element consists of a subset of origin pixel and its eight neighbors. Generally, local decomposition of a structuring element reduces the amount of computation required for morphological operations with the structuring element. A unique feature of our approach is the use of linear integer programming technique to determine optimal local decomposition that guarantees the minimal amount of computation. We defined a digital convex polygon, which, in turn, is defined as a convex structuring element, and formulated the necessary and sufficient conditions to decompose a digital convex polygon into a set of basis digital convex polygons. We used a set of linear equations to represent the relationships between the edges and the positions of the original convex polygon, and those of the basis convex polygons. Further. a cost function was used represent the total processing time required for computation of dilation/erosion with the structuring elements in a decomposition. Then integer linear programming was used to seek an optimal local decomposition, that satisfies the linear equations and simultaneously minimize the cost function.

• 한국지능시스템학회논문지
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• 제18권5호
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• pp.617-623
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• 2008

본 논문에서는 중심이동과 국부기저영상을 이용한 동작인식 기법을 제안하였다. 여기서 중심이동은 1차 모멘트 평형에 기반을 둔 것으로 위치나 크기 변화에 강건한 동작영상을 얻기 위함이고, 국부기저영상의 추출은 독립성분분석 기법에 기반을 둔 것으로 각 동작들마다에 포함된 통계적으로 독립인 동작특징들의 집합을 얻기 위함이다. 특히 국부기저영상을 빠르게 추출하기 위해 뉴우턴(Newton)법의 고정점 알고리즘에 기반을 둔 독립성분분석을 이용하였다. 제안된 기법을 240*215 픽셀의 160(1명*10종류*16동작)개 동물표현의 수화 동작영상을 대상으로 city-block, Euclidean, 그리고 negative angle의 척도들을 분류척도로 이용하여 실험하였다. 실험결과, 제안된 기법은 국부고유영상을 이용한 방법과 중심이동을 거치지 않는 국부기저영상을 이용하는 기법보다 각각 우수한 인식성능이 있음을 확인하였다.

• International Journal of Precision Engineering and Manufacturing
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• 제8권1호
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• pp.3-10
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• 2007

A new approach based on implicit surface interpolation combined with domain decomposition is proposed for filling complex-shaped holes in a large polygon model, A surface was constructed by creating a smooth implicit surface from an incomplete polygon model through which the actual surface would pass. The implicit surface was defined by a radial basis function, which is a continuous scalar-value function over the domain $R^{3}$. The generated surface consisted of the set of all points at which this scalar function is zero. It was created by placing zero-valued constraints at the vertices of the polygon model. The well-known domain decomposition method was used to treat the large polygon model. The global domain of interest was divided into smaller domains in which the problem could be solved locally. The LU decomposition method was used to solve the set of small local problems; the local solutions were then combined using weighting coefficients to obtain a global solution. The validity of this new approach was demonstrated by using it to fill various holes in large and complex polygon models with arbitrary topologies.

• Bulletin of the Korean Chemical Society
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• 제32권10호
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• pp.3614-3617
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• 2011

A density functional theory method with the local basis set was employed to perform slab calculations to study thiolate-induced surface reconstruction structures of butylthiolates (ButS) with c($4{\times}2$) superlattice of the Au(111) surface. The slab calculations indicate that the most stable adsorption structure is the ButS-Au (adatom)-SBut complex form, which is in good agreement with the reported experiments and theoretical results for thiolates with shorter alkyl chains. The cis form of ButS-Au (adatom)-SBut motifs is preferred by 0.11 eV with respect to the trans form, and by 0.15 eV over the mixed cis-trans configurations due to the steric hindrance between adjacent butyl groups. It appears that the motif of Au adatom on the Au(111) surface is favored even for butylthiolate.

• The Journal of the Acoustical Society of Korea
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• 제18권3E호
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• pp.37-43
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• 1999

In this paper, we present a new technique for the optimal local decomposition of convex structuring elements on a hexagonal grid, which are used as templates for morphological image processing. Each basis structuring element in a local decomposition is a local convex structuring element, which can be contained in hexagonal window centered at the origin. Generally, local decomposition of a structuring element results in great savings in the processing time for computing morphological operations. First, we define a convex structuring element on a hexagonal grid and formulate the necessary and sufficient conditions to decompose a convex structuring element into the set of basis convex structuring elements. Further, a cost function was defined to represent the amount of computation or execution time required for performing dilations on different computing environments and by different implementation methods. Then the decomposition condition and the cost function are applied to find the optimal local decomposition of convex structuring elements, which guarantees the minimal amount of computation for morphological operation. Simulation shows that optimal local decomposition results in great reduction in the amount of computation for morphological operations. Our technique is general and flexible since different cost functions could be used to achieve optimal local decomposition for different computing environments and implementation methods.

• 한국정밀공학회지
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• 제23권1호
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• pp.174-184
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• 2006

In order to fill the holes with complex shapes in the large polygon model, a new approach which is based on the implicit surface interpolation method combined with domain decomposition method is presented. In the present study, a surface is constructed by creating smooth implicit surface from the incomplete polygon model through which the surface should pass. In the method an implicit surface is defined by a radial basis function, a continuous scalar-valued function over the domain $R^3$ The generated surface is the set of all points at which this scalar function takes on the value zero and is created by placing zero-valued constraints at the vertices of the polygon model. In this paper the well-known domain decomposition method is used in order to treat the large polygon model. The global domain of interest is divided into smaller domains where the problem can be solved locally. LU decomposition method is used to solve a set of small local problems and their local solutions are combined together using the weighting coefficients to obtain a global solution. In order to show the validity of the present study, various hole fillings are carried out fur the large and complex polygon model of arbitrary topology.

• 정보처리학회논문지A
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• 제8A권1호
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• pp.56-62
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• 2001

This paper presents a neural network based variable structure control scheme for nonlinear systems. In this scheme, a set of local variable structure control laws are designed on the basis of the linear models about preselected representative points which cover the range of the system operation of interest. From the combination of the set of local variable structure control laws, neural networks infer the approximate control input in between the operating points. The neural network based variable structure control alleviates the effects of model uncertainties, which cannot be compensated by the control techniques using feedback linearization. It also relaxes the discontinuity in the system’s behavior that appears when the control schemes based on the family of the linear models are applied to nonlinear systems. Simulation results of a ball and beam system, to which feedback linearization cannot be applied, demonstrate the feasibility of the proposed method.

• Journal of Electrical Engineering and Technology
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• 제13권6호
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• pp.2511-2520
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• 2018

In this study, Multi-Radial Basis Function Support Vector Machine (Multi-RBF SVM) classifier is introduced based on a composite kernel function. In the proposed multi-RBF support vector machine classifier, the input space is divided into several local subsets considered for extremely nonlinear classification tasks. Each local subset is expressed as nonlinear classification subspace and mapped into feature space by using kernel function. The composite kernel function employs the dual RBF structure. By capturing the nonlinear distribution knowledge of local subsets, the training data is mapped into higher feature space, then Multi-SVM classifier is realized by using the composite kernel function through optimization procedure similar to conventional SVM classifier. The original training data set is partitioned by using some unsupervised learning methods such as clustering methods. In this study, three types of clustering method are considered such as Affinity propagation (AP), Hard C-Mean (HCM) and Iterative Self-Organizing Data Analysis Technique Algorithm (ISODATA). Experimental results on benchmark machine learning datasets show that the proposed method improves the classification performance efficiently.

• 대한수학회보
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• 제38권4호
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• pp.635-641
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• 2001

A limit point p of a Mobius group acting on$ B^m$ is called a concentration point if for every sufficiently small connected open neighborhood of p, the set of translates contains a local basis for the topology of p. For the case of two generator Schottky groups acting on $B^2$, we give characterizations for several different kinds of limit points.