• Spatial Information Research
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• v.20 no.2
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• pp.45-57
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• 2012

Recently, local governments in Korea are promoting the rapid development of marine for delineating jurisdictional sea area. The importance of a maritime boundary has being emphasized, as jurisdictional sea area disputes among local governments have been increasing. The absence of the delineating standard of maritime boundary has become a source of contention between neighborhood local governments. So the delineating standard of maritime boundary in Korea will be required. The purpose of this study is to derive an improvement plan for the scientific delimitation standard of maritime boundary by analyzing "A hydrographic survey guideline for confirmation of maritime boundary". The results of this study are as follows. Firstly, we defined the concept of the delimitation standard of maritime boundary. Secondly, we set the boundary, factors and processes of the delineating standard of maritime boundary through classifying them in detail. Lastly, we suggested the makeup of a conflict adjustment committee for preventing jurisdictional sea area disputes among local governments.

• Journal of the Korean Geographical Society
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• v.48 no.6
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• pp.914-928
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• 2013

Establishment of limits and names for oceans and seas is necessary for a safety of navigation. Even if there are no national and international standard for the delimitation of sea boundaries, we can take guidelines for the delimitation of sea boundaries through the analysis of IHO official publications, Limits and Names for Oceans and Sea; S-23. This paper shows the changes of the spatial limit of seas since first edition publication, and the standards for a delimitation of oceans and seas were analyzed using S-23 4th edition draft(2002) in terms of physical geographic features. The generic terms of S-23 include Ocean, Sea, Channel, Passage, Strait, Sound, Gulf, Bay and Bight, and each generic term shows hierarchical structures. Several seas show different characteristics compared with definitions of IHO dictionary. Sea boundaries are delimited by longitude and latitude, cape, river mouth, sandbar, and so on. Undersea features such as a shelf, trench, trough, rise, bank and reef are also important features for delimitation of sea boundary. Especially, seas that are delimited by undersea feature are mainly located Arctic and Southern ocean area in S-23 4th edition. Advanced knowledge of marine science with a technical advance might affect to delimit for sea boundary.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.4
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• pp.495-508
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• 2019

Tidal datums are key and basic information used in fields of navigation, coastal structures' design, maritime boundary delimitation and inundation warning. In Korea, the Approximate Lowest Low Water (ALLW) and the Approximate Highest High Water (AHHW) have been used as levels of tidal datums for depth, coastline and vertical clearances in hydrography and coastal engineering fields. However, recently the major maritime countries including USA, Australia and UK have adopted the Lowest Astronomical Tide (LAT) and the Highest Astronomical Tide (HAT) as the tidal datums. In this study, 1-hr interval 19-year sea level records (1999-2017) observed at 9 tidal observation stations along the west and south coasts of Korea were used to calculate LAT and HAT for each station using 1-minute interval 19-year tidal prediction data yielded through three tidal harmonic methods: 19 year vector average of tidal harmonic constants (Vector Average Method, VA), tidal harmonic analysis on 19 years of continuous data (19-year Method, 19Y) and tidal harmonic analysis on one year of data (1-year Method, 1Y). The calculated LAT and HAT values were quantitatively compared with the ALLW and AHHW values, respectively. The main causes of the difference between them were explored. In this study, we used the UTide, which is capable of conducting 19-year record tidal harmonic analysis and 19 year tidal prediction. Application of the three harmonic methods showed that there were relatively small differences (mostly less than ±1 cm) of the values of LAT and HAT calculated from the VA and 19Y methods, revealing that each method can be mutually and effectively used. In contrast, the standard deviations between LATs and HATs calculated from the 1Y and 19Y methods were 3~7 cm. The LAT (HAT) differences between the 1Y and 19Y methods range from -16.4 to 10.7 cm (-8.2 to 14.3 cm), which are relatively large compared to the LAT and HAT differences between the VA and 19Y methods. The LAT (HAT) values are, on average, 33.6 (46.2) cm lower (higher) than those of ALLW (AHHW) along the west and south coast of Korea. It was found that the S_a and N₂ tides significantly contribute to these differences. In the shallow water constituents dominated area, the M₄ and MS₄ tides also remarkably contribute to them. Differences between the LAT and the ALLW are larger than those between the HAT and the AHHW. The asymmetry occurs because the LAT and HAT are calculated from the amplitudes and phase-lags of 67 harmonic constituents whereas the ALLW and AHHW are based only on the amplitudes of the 4 major harmonic constituents.

• 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.