• Korean Journal of Computational Design and Engineering
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• v.20 no.4
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• pp.328-336
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• 2015

We proposed a methodology to automatically extract the requirements from the documents and check the consistency and traceability among them. The documents include not only text but also PDF or image files. We also suggest a method to visualize the result with maps, numbers, and graphs. By comparing the results with those of manual reviews from experts, we show that it is necessary to use knowledge-based method in future instead of the wordbased method for improving the reliability. The results can be applied effectively for already existing documents.

• Journal of KIISE:Software and Applications
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• v.32 no.4
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• pp.290-299
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• 2005

Stealing the source code of a program is a serious problem not only in a moral sense but also in a legal sense. However, it is not clear whether the code of a program is copied from another or not. There was a program similarity checker detecting code-copy by comparing the syntax trees of programs. However this method has a limitation that it cannot detect the code-copy attacks when the attacker modifies the syntax of the program on purpose. We propose a program similarity check by program control graph, which reveals not only syntax information but also control dependancy. Our method can detect the code-copy attacks that do not change control dependancy Moreover, we define what code-copy means and establish the connection between code-copy and similarity of program control graph: we prove that two programs are related by copy congruence if and only if the program control graphs of these programs are equivalent. We implemented our method on a functional programming language, nML. The experimental results show us that the suggested method can detect code similarity that is not detected by the existing method.

• The Transactions of the Korea Information Processing Society
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• v.3 no.7
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• pp.1659-1668
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• 1996

Graph grammars generate graph languages while string grammars generate string languages which are the subset of graph languages. One of the most successful graph grammars models is the NLC grammars, which gen-erate graphs by replacing a node by a node by a graph through node labels. For grammars generating hypergraphs which are the superset of graphs, there are CFHG grammars, which replace a hyperedge by a hypergraph through their preidentified gluing points, an extension of CFHG grammars called HH grammars, which replace a handle by a hypergraph through the rewriting mechanism that can also duplicate or delete the hyperedges surrounding the replaced handle, and finally HRNCE grammars, which replace a handle by a hypergraph through an eNCE way of rewriting, In this paper, we compare the language-generating power of HRNCE grammars with that a graph grammars mentioned above by comparing graph langrages generated by them, respecti vely.

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.6
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• pp.759-764
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• 2005

In this paper we describe a face recognition using EBGM(Elastic Bunch Graph Matching) method. Usally, the PCA and LDA based face recognition method with the low-dimensional subspace representation use holistic image of faces, but this study uses local features such as a set of convolution coefficients for Gabor kernels of different orientations and frequencies at fiducial points including the eyes, nose and mouth. At pre-recognition step, all images are represented with same size face graphs and they are used to recognize a face comparing with each similarity for all images. The proposed algorithm has less computation time due to simplified face graph than conventional EBGM method and the fuzzy matching method for calculating the similarity of face graphs renders more face recognition results.

• Fashion & Textile Research Journal
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• v.9 no.4
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• pp.418-424
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• 2007

The purpose of this study is to propose a standard of converting 3D shape of men in twenties to 2D patterns. This can be a basis for scientific and automatic pattern making for high quality custom clothes. Firstly, representative 3D body shape of men was modeled. Then the 3D model was divided into 3 shells, front, side and back. Among them, the front shell was divided into 4 blocks by bust line and princess line. Secondly, curves are generated on each block according to matrix combination by grid method. Then triangles were developed into 2D pieces by reflecting the 3D curve length. The grid was arranged to maintain outer curve length. Next, the area of developed pieces and block were calculated and difference ratio between the block area and the developed pieces' area is calculated. Also, area difference ratio by the number of triangles is calculated. The difference ratio was represented as graphs and optimal section is selected by the shape of graphs. The optimal matrix was set considering connection with other blocks. Curves of torso upper front shell were regenerated by the optimal matrix and developed into pieces. We validated it's suitability by comparing difference ratio between the block area and the developed pieces' area of optimal section. The results showed that there was no significant difference between block area and the pieces' area developed by optimal matrix. The optimal matrix for 2D developing could be characterized as two types according to block's shape characteristics, one is affected by triangle number, the other is affected by number of raws more than columns. Through this study, both the 2D pattern developing from 3D body shape and 3D modeling from 2D pattern is possible, so it's standardization also possible.

• The Journal of the Korea Contents Association
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• v.13 no.11
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• pp.37-47
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• 2013

Recently, lots of research results on program comparison have been reported since the code theft become frequent as the increase of code mobility. This paper proposes a plagiarism detection method using class structures. The proposed method constructs a graph representing the referential relationship between the member variables and the methods. This relationship is shown as a bipartite graph and the test for graph isomorphism is applied on the set of graphs to measure the similarity of the programs. In order to measure the effectiveness of this method, an experiment was conducted on the test set, the set of Java source codes submitted as solutions for the programming assignments in Object-Oriented Programming course of Pusan National University in 2012. In order to evaluate the accuracy of the proposed method, the F-measure is compared to those of JPlag and Stigmata. According to the experimental result, the F-measure of the proposed method is higher than those of JPlag and Stigmata by 0.17 and 0.34, respectively.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.12
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• pp.1682-1687
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• 2020

We study the problem of sampling a subset of nodes of graphs for bandlimited graph signals such that the signal values on the sampled nodes provide the most information in order to reconstruct the original graph signal. Instead of directly minimizing the reconstruction error, we focus on minimizing the upper bound of the reconstruction error to reduce the complexity of the selection process. We further simplify the upper bound by applying useful approximations to propose a low-weight greedy selection process that is iteratively conducted to find a suboptimal sampling set. Through the extensive experiments for various graphs, we inspect the performance of the proposed algorithm by comparing with different sampling set selection methods and show that the proposed technique runs fast while preserving a competitive reconstruction performance, yielding a practical solution to real-time applications.

• Journal of the Korea Society for Simulation
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• v.19 no.4
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• pp.129-137
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• 2010

Currently used shortest path search algorithms involve graphs with vertices and weighted edges between each vertex. However, when finding the shortest path with a randomly shaped obstacle(an island, for instance) positioned in between the starting point and the destination, using such algorithms involves high memory inefficiency and is significantly time consuming - all positions in the map should be considered as vertices and every line connecting any of the two adjacent vertices should be considered an edge. Therefore, we propose a new method for finding the shortest path in such conditions without using weighted graphs. This algorithm will allow finding the shortest obstacle bypass given only the positions of the obstacle boundary, the starting point and the destination. When the row and column size of the minimum boundary rectangle to include an obstacle is m and n, respectively, the proposed algorithm has the maximum time complexity, O(mn). This performance shows the proposed algorithm is very efficient comparing with the currently used algorithms.

• Journal of the Korean Society of Clothing and Textiles
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• v.44 no.2
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• pp.224-236
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• 2020

In this study, the 4th (1997) and 6th (2013) direct measurements of Size Korea compared the changing shape of women between the ages of 12 and 18. Comparing the items of height and length, the height and shoulder height were significantly reduced, the waist height was not significantly different, and the height of the upper hip was significantly increased, resulting in a smaller upper torso ratio and a higher lower torso rate. The width and thickness associated with human obesity, the circumference items and obesity levels often increased significantly with the change of the times, indicating that the overall body size was increased and that the chest area was changed to a cylindrical shape with changes in the breast equilibrium. Comparing agespecific measurements with graphs analyzing the trend of change in growth, the results showed that the change in 1997 was minimal since age 14; however, a continuous increase was achieved in 2013 that corresponded to the age at which growth is complete. The results of these studies are expected to be used as basic data to predict pattern design, body implementation, and trends in shape changes for young women.

• Journal of Korean Society of Forest Science
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• v.82 no.1
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• pp.17-25
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• 1993

Tree-ring data of subalpine conifers growing in Korea were analyzed to evaluate the possibility of enhanced tree growths due to increased atmospheric carbon dioxide. A total of 64 trees of three species(Taxus cuspidata, Pinus koraiensis, Abies koreana) were sampled from three mountain ranges (Seolak, Sobaek, Chiri) at 1200~1750m(above sea level) and four chronologies were developed in spans of 209~412 years. No apparent growth increases were found in the graphs of chronologies. As comparing the growths of 1900-1949 and 1950-1989 period, only one chronology possessed higher mean growth in the post-1950 period. Growth increase found in the Pinus koraiensis chronology from Mt. Seolak was 8% but it could not be solely attributed to increased carbon dioxide concentration.