• Korean Journal of Mathematics
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• 제18권1호
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• pp.53-61
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• 2010

In this work, we consider an elliptic system of three equations in dimension greater than one. We prove that the system has at least three nontrivial solutions by applying a linking theorem.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.1048-1052
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• 2004

In this work, we have investigated a role of linking parameter in Pulse-Coupled Neural Network(PCNN) which is suggested to explain the synchronous activities among neurons in the cat cortex. Then we have found a method to determine the linking parameter for a satisfactory face detection performance in a given color image. Face detection algorithm which uses the color information is independent on pose, size and obstruction of a face. But the use of color information encounters some problems arising from skin-tone color in the background, intensity variation within faces, and presence of random noise and so on. Depending on these conditions, PCNN's linking parameters should be selected an appropriate values. First we obtained the mean and variance of the skin-tone colors by experiments. Then, we introduced a preprocess that the pixel with a mean value of skin-tone colors has the highest level value (255) and the other pixels have values between 0 and 255 according to normal distribution with a variance. This preprocessing leads to an easy decision of the linking parameter of the Pulse-Coupled Neural Network. Through experiments, it is verified that the proposed method can improve the face detection performance compared to the existing methods.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2010년 춘계학술발표회 논문집
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• pp.23-25
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• 2010

In this paper, we studied linking method for updating navigation map with new address map. This method is hierarchical as we chose candidate using attribute data for geometry matching. Limiting a matching range, we conducted a experiment ICP with geometry matching. As a result, for linking method it's quite satisfied but for updating method, we decided that we have to do more precise method for updating.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.408-410
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• 2003

In this paper, an improved gradient direction assisted linking algorithm is proposed. This algorithm begins with initial seeds satisfying some local criteria. Then it will search along the direction provided by the initial point. A window will be generated in the gradient direction of the current point. Instead of the conventional method which only considers the value of the local salient structure, an improved mathematical model is proposed to describe the desired linear features. This model not only considers the value of the salient structure but also the direction of it. Furthermore, the linking problem under this model can be efficiently solved by dynamic programming method. This algorithm is tested for linear features detection in IKONOS images. The result demonstrates this algorithm is quite promising.

• Proceedings of the Jangjeon Mathematical Society
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• 제20권2호
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• pp.183-191
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• 2017

We get one theorem that there exist solutions for the fourth order semi- linear elliptic Dirichlet boundary value problem with fully nonlinear term. We prove this result by the critical point theory and the variation of linking method.

• Korean Journal of Mathematics
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• 제17권3호
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• pp.331-340
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• 2009

We show the existence of nonconstant periodic solution for the nonlinear Hamiltonian systems with some nonlinearity. We approach the variational method. We use the critical point theory and the variational linking theory for strongly indefinite functional.

• 정보과학회 논문지
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• 제43권9호
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• pp.1043-1051
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• 2016

트위터 문서는 웹 문서에 비해 길이가 짧기 때문에 웹 기반의 개체 링킹 기법을 그대로 적용시킬 수 없어 사용자 정보나 집단의 정보를 활용하는 방법들이 시도되고 있다. 하지만, 트윗의 개수가 충분하지 않은 사용자의 경우 데이터 희소성 문제가 여전히 발생하고 관련이 없는 집단의 정보를 사용할 경우 링킹의 결과에 악영향을 미칠 수 있다. 본 논문에서는 기존 연구의 문제를 해결하기 위해 단일 트윗 내의 의미 관련도 뿐만 아니라 사용자의 트윗 집합과 다른 사용자들의 트윗 집합까지 고려하여 데이터 희소성을 해결하고, 관련성이 높은 사용자들의 트윗 정보에 가중치를 주어 트윗 개체 링킹의 성능을 높이고자 한다. 실제 트위터 데이터를 활용한 실험을 통해 제안하는 트윗 개체 링킹 기법이 기존의 기법에 비해 높은 성능을 가지며, 유사도가 높은 사용자의 정보를 사용하는 것이 트윗 개체 링킹에서 데이터 희소성 해결과 링킹 정확도 향상에 연관성이 있음을 보였다.

• 대한원격탐사학회지
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• 제27권6호
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• pp.717-728
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• 2011

An efficient method for the unsupervised classification of high resolution imagery is suggested in this paper. It employs pixel-linking and merging based on the adjacency graph. The proposed algorithm uses the neighbor lines of 8 directions to include information in spatial proximity. Two approaches are suggested to employ neighbor lines in the linking. One is to compute the dissimilarity measure for the pixel-linking using information from the best lines with the smallest non. The other is to select the best directions for the dissimilarity measure by comparing the non-homogeneity of each line in the same direction of two adjacent pixels. The resultant partition of pixel-linking is segmented and classified by the merging based on the regional and spectral adjacency graphs. This study performed extensive experiments using simulation data and a real high resolution data of IKONOS. The experimental results show that the new approach proposed in this study is quite effective to provide segments of high quality for object-based analysis and proper land-cover map for high resolution imagery of urban area.

• Macromolecular Research
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• 제17권11호
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• pp.926-930
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• 2009

A new method for encapsulating nanomaterials within intermediary layer cross-linked (ILCL) polymeric micelles using a bifunctional photo-cross-linking agent was developed. For ILCL polymeric micelles, an amphiphilic triblock copolymer of poly(ethylene glycol)-b-poly(2-hydroxyethyl methacrylate)-b-poly(methyl methacrylate) (PEG-PHEMA-PMMA) was synthesized via consecutive atom transfer radical polymerization (ATRP), Di(4-hydroxyl benzophenone) dodecanedioate (BPD) was used as a bifunctional photo-cross-linking agent. The PMMA-tethered Au nanoparticles and BPD, or pyrene and BPD were encapsulated in the PEG-PHEMA-PMMA micelles, and their intermediary layers were photo-cross-linked by UV irradiation for 1 h. The HEMA units donated labile hydrogens to the excited-state benzophenone groups in BPD, and they were subsequently cross-linked by BPD through radical-radical combination. The spherical structures of the PEG-PHEMA-PMMA micelles containing the Au nanoparticles or pyrene were unaffected by the photo-cross-linking process.

• Korean Journal of Mathematics
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• 제22권2호
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• pp.355-365
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• 2014

We show the existence of nontrivial solutions for some fourth order elliptic boundary value problem with fully nonlinear term. We obtain this result by approaching the variational method and using a linking theorem. We also get a uniqueness result.