• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.558-561
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• 2009

In this paper, we propose Simple Frame Marker(SFMarker) to support recognition of characters and images included in a marker in augmented reality. If characters are inserted inside of marker and are recognised using Optical Character Recognition(OCR), it doesn't need marker learning process before an execution. It also reduces visual disturbance compared to 2D barcode marker due to familarity of characters. Therefore, proposed SFMarker distinguishes Square SFMarker that embeds images from Rectangle SFMarker with characters according to ratio of marker and applies different recognition algorithms. Also, in order to reduce preprocessing of character recognition, SFMarker inserts direction information in border of marker and extracts it to execute character recognition fast and correctly. Finally, since the character recognition for every frame slows down tracking speed, we increase the speed of recognition process using the result of character recognition in previous frame when frame difference is low.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.6
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• pp.867-874
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• 2016

Although shrimps belonging to family Crangonidae are known to be genetically divergent and ecologically important among the various benthos, any of their mitochondrial genome has not been reported yet. We here determined the complete mitochondrial genome sequence of Crangon hakodatei (Rathbun, 1902), which was collected from East China Sea ($124^{\circ}E$ and $34.5^{\circ}N$). Total mitochondrial genome length of C. hakodatei was 16,060 bp, in which 13 proteins, 2 ribosomal RNAs, 22 transfer RNAs and a putative control region were encoded. Secondary structure prediction analysis showed that twenty tRNA genes exhibit the conserved structure but two genes, $tRNA^{Cys}$ and $tRNA^{Ser}$ (AGN), lack T and D arm, respectively. Based on the sequence similarity of the COI region from the currently reported five species belonging to genus Crangonidae, C. hakodatei was most closely related to Crangon crangon. Phylogenetic analysis of full COXI genes belonging to infraorder Caridea showed that only crangonid shrimps were clustered together with those of Dendrobranchiata. Gene order were well conserved from Penaeoidea to Caridea but $tRNA^{Pro}$ and $tRNA^{Thr}$ in Palaemonid shrimp were flipped each other by the recombination. Further study about mitochondrial genome sequences of shrimps belonging to Crangonidae should be made to know better about their evolutional relationships with other those in infraorder Caridea.

• Genomics & Informatics
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• v.21 no.3
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• pp.39.1-39.15
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• 2023

DNA barcoding without assessing reliability and validity causes taxonomic errors of species identification, which is responsible for disruptions of their conservation and aquaculture industry. Although DNA barcoding facilitates molecular identification and phylogenetic analysis of species, its availability in clariid catfish lineage remains uncertain. In this study, DNA barcoding was developed and validated for clariid catfish. 2,970 barcode sequences from mitochondrial cytochrome c oxidase I (COI) and cytochrome b (Cytb) genes and D-loop sequences were analyzed for 37 clariid catfish species. The highest intraspecific nearest neighbor distances were 85.47%, 98.03%, and 89.10% for COI, Cytb, and D-loop sequences, respectively. This suggests that the Cytb gene is the most appropriate for identifying clariid catfish and can serve as a standard region for DNA barcoding. A positive barcoding gap between interspecific and intraspecific sequence divergence was observed in the Cytb dataset but not in the COI and D-loop datasets. Intraspecific variation was typically less than 4.4%, whereas interspecific variation was generally more than 66.9%. However, a species complex was detected in walking catfish and significant intraspecific sequence divergence was observed in North African catfish. These findings suggest the need to focus on developing a DNA barcoding system for classifying clariid catfish properly and to validate its efficacy for a wider range of clariid catfish. With an enriched database of multiple sequences from a target species and its genus, species identification can be more accurate and biodiversity assessment of the species can be facilitated.