• Journal of the Korean Mathematical Society
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• v.48 no.4
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• pp.691-702
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• 2011

The competition graph of a digraph D is a graph which has the same vertex set as D and has an edge between x and y if and only if there exists a vertex v in D such that (x, v) and (y, v) are arcs of D. For any graph G, G together with sufficiently many isolated vertices is the competition graph of some acyclic digraph. The competition number k(G) of a graph G is defined to be the smallest number of such isolated vertices. In general, it is hard to compute the competition number k(G) for a graph G and it has been one of important research problems in the study of competition graphs. In this paper, we compute the competition numbers of Hamming graphs with diameter at most three.

• The Journal of the Korea institute of electronic communication sciences
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• v.17 no.5
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• pp.801-808
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• 2022

Research on how to embed knowledge in large-scale Linked Data and apply neural network models for entity matching is relatively scarce. The most fundamental problem with this is that different labels lead to lexical heterogeneity. In this paper, we propose an extended GCN (Graph Convolutional Network) model that combines re-align structure to solve this lexical heterogeneity problem. The proposed model improved the performance by 53% and 40%, respectively, compared to the existing embedded-based MTransE and BootEA models, and improved the performance by 5.1% compared to the GCN-based RDGCN model.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.7B
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• pp.664-672
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• 2002

This paper analyzes a sequential estimator with flexible structure for rapid acquisition of the m-sequence signals. If the received PN chips stored in the estimator's internal registers as initial loading values include one error, this chip with error can be corrected through multiple local PN code generators to achieve high-speed acquisition performance. Hamming distance between regenerated local PN codes from the proposed system and received PN code is compared with given threshold to choose a possible correct path and to declare success of the code acquisition. Using signal flow graph, average acquisition time that depends on detection and false alarm probability is calculated. By modifying generally used matched filter structure for PN code acquisition, the proposed system provides flexible structure and rapid acquisition process.