• Proceedings of the KSRS Conference
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• v.2
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• pp.760-763
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• 2006

In this paper, a small portion of coastline on the EAST SEA was studied using CORONA panoramic satellite photo and 1:5000 Korean National Topographic Map. The project site near Kangneung city was 3 Km shoreline on the Kangmoon Beach and the SongJeong Beach, which have suffered from severe erosion. The first and the most important step was to rectify a CORONA image over the project site. A rigid mathematical model and a heuristic polynomial transformation were used for the purpose. The rectified image was overlaid with 1:5000 Korean National Topographic Map produced by aerial mapping. Among numerous methods for shoreline erosion measurement, area-based approach was chosen and used for the computation for annual shoreline recession. The final result of the analysis was that the average recession in the period of 1963-1998 was 33.6m and the annual rate was 0.96m.

• Korean Journal of Geomatics
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• v.2 no.2
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• pp.91-98
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• 2002

Lands along the coast may be submerged in high water because of erosion by sea water, collapsing by itself, excavation by animals, and by tidal movement. From a cadastral point of view, some mistakes in registering a parcel located along the coast may cause the parcel to seem to be collapsed. Therefore, geological, physical oceanographic, and cadastral and topographic investigation are necessary to verify that the submerged land in high water collapsed after it was registered. This paper presents a cadastral and topographic investigation for proving a parcel has collapsed under the sea after registered. In this study, cadastral records and the boundary on cadastral maps were examined carefully to find any errors in them. If the topographic maps were drawn when the parcel was registered, it is good proof of topography of the land at that time. Topographic maps drawn recently were compared to those in the 1900s and in 1970s. In conclusion, cadastral records and maps as well as topographic maps play an important role in proving whether lands along the coast were collapsed or not.

• Journal of Environmental Science International
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• v.8 no.1
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• pp.1-6
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• 1999

This study was carried out to evaluate off-shore water quality and to draw marine pollution map to Southern sea in Korea by bioassay using gametes and early development system of Asterias amurensis. From the bioassay, it was determined that the water qualites of Southern sea maintained the grade II, because development of A. amurensis were moderately inhibited. However, Sunchon, Kwangyang, and Jinhae Bay belonged to grade III, because development of A. amurensis were strongly inhibited. This could be due to the inflows of several river systems and poor water circulation. The water quality at Yosu island was the grade I, because A. amurensis were not inhibited in its early development.

• Atmosphere
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• v.20 no.2
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• pp.63-71
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• 2010

In this study, we derived the wind speed at 50 m and 80 m above sea level from 567 stations over a period of 1 year and correlated to measured wind speed at 5 radiosonde sites. From these correlations, we derived and analyzed the spatial distribution of wind map over Korea based on hourly observational data recorded over a period of 5 years from 2004 to 2008. As a results, wind speed is generally high over seashores, mountains, and islands. Mean wind speed over Korea at 50 and 80 m above sea level for 5 years during 2004 to 2008 seasonally are highest at Spring, and then followed by Winter, Fall, and Summer. In 76 (14%) stations, mean wind speed at 80 m above sea level for 5 years during 2004 to 2008 are greater than $5ms^{-1}$. The prevailing winds over Korea at 80 m above sea level for 5 years during 2004 to 2008 are North (44%), Northwest (16%), and West (15%). In 99 stations, the % of wind faster than $5ms^{-1}$ was higher than 40%, and in 62 stations, the % of wind faster than $5ms^{-1}$ was higher than 50%. In 178 station, the % of prevailing winds was higher than 30%, and there are 7 stations which also have wind speeds over $5ms^{-1}$, ranking from highest to lowest, Dongsong, Daegwallyeong, Baekun Mt., Hyangrobong Mt., Sorak Mt., Gosan, and Misiryeong Mt..

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.3
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• pp.525-532
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• 2021

In the ocean, it is difficult to separate the effects of one cause due to the multiple causes, but the self-organizing map can be analyzed by adding other factors to the cluster result. Therefore, in this study, the results of the clustering of sea level data were applied to sea surface temperature. Sea level data was clustered into a total of 6 nodes. The difference between sea surface temperature and sea level height has a one-month delay, which applied sea surface temperature data a month ago to the clustered results. As a result of comparing the mean of sea surface temperature of 140 to 150°E, where the sea surface temperature was variously distributed, in the case of nodes 1, 3, and 5, it was possible to find a meandering sea surface temperature distribution that is clearly distinguished from the sea level data. While nodes 2, 4 and 6, the sea surface temperature distribution was smooth. In this study, sea surface temperature data were applied to the clustered results of sea level data, but later it is necessary to apply wind or geostrophic velocity data to compare.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.22 no.4
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• pp.151-171
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• 2017

Most of oceanic current maps in the secondary school science and earth science textbooks have been made on the base of extensive in-situ measurements conducted by Japanese oceanographers during 1930s. According to up-to-date scientific knowledge on the currents in the Yellow Sea and the East China Sea (YES), such maps have significant errors and are likely to cause misconceptions to students, thus new schematic map of ocean currents is needed. The currents in the YES change seasonally due to relatively shallow water depths, complex terrain, winds, and tides. These factors make it difficult to construct a unified ocean current map of the YES. Sixteen major items, such as the flow of the Kuroshio Current into the East China Sea and its northward path, the origin of the Tsushima Warm Current and its path into the Korea Strait, the path of Taiwan Warm Current, the Jeju Warm Current, the runoff pattern of the Yangtze River flow, the routes of the northward Yellow Sea Warm Current, the Chinese Coastal Current, and the West Korea Coastal Current off the west coast of the Korean Peninsula, were selected to produce the schematic current map. Review of previous scientific researches, in-depth discussions through academic conferences, expert discussions, and consultations for three years since 2014 enabled us to produce the final ocean current maps for the YES after many revisions. Considering the complexity of the ocean currents, we made seven ocean current maps: two representative current patterns in summer and winter, seasonal current maps for upper layer and lower layer in summer and winter, and one representative surface current map. It is expected that the representative maps of the YES, connected to the current maps of the East Sea and the Northwest Pacific Ocean, would be widely utilized for diverse purposes in the secondary-school textbooks as well as high-level educational purposes and even for scientific scholarly experts.

• Journal of the Korean earth science society
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• v.34 no.7
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• pp.633-644
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• 2013

This study evaluates wind farm efficiency at Haengwon in Jeju Island. The actual energy production at Haengwon wind farm is compared with the estimated energy production based on Korean wind map which is developed at the National Institute of Meteorological Research/KMA. The validation of wind map at Gujwa located near the Haengwon wind farm shows that the wind speed is overestimated. The diurnal variation of wind speed shows a maximum value in the afternoon due to the effect of sea-land breeze. The ratio of the actual energy production at Haengwon wind farm and the estimated energy production based on the Korean wind map is 24.8%, while the distribution of energy frequency is similar each other. The difference of energy production is caused by mechanical error of the turbine and the overestimation of the simulated wind map. This study will contribute to the repowering of turbines for improving the efficiency of wind farm in the future.

• Journal of the Korean earth science society
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• v.25 no.8
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• pp.739-747
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• 2004

This study was to promote meaning ways of leaning and observe the influence of concept maps on middle school students' conceptual formation with regards to the topic of the 'sea water'. Concept map is one way to examine a leaner's conceptual formation process. The subjects of this study consisted of four classes within the first grade students of a Busan middle school, which were divided into two groups: the experimental group which applied concept map teaching and the ordinary teaching group. This study was carried out before and after class, examining the science leaning achievement, self-directed leaning characteristics, and awareness change on the concept maps. The result of this study was as follows: First, the leaning achievement of middle school students was positively affected by the use of concept maps. Second, the teaching method with concept map was more effective self-directed leaning characteristics compared to the ordinary one. Third, concept map teaching was a positive reaction to conceptual formation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.4
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• pp.272-281
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• 2008

Seasonal and annual variation in the species composition of bag-net catch in the coastal waters of Incheon, Korea were examined from April 2000 to November 2004. To analyze seasonal variation of the fisheries data, we implemented a self-organizing map(SOM), an unsupervised artificial neural network, with the catch amount of 97 species. Over 5 years, we caught 68 species of fish, 23 species of crustaceans and six species of cephalopods. The total number of fish species were gradually increased during the study period. The number of species was higher during the spring than the autumn. The SOM identified four groups of the sampling months based on seasonal changes in communities. In the spring, the dominant species were Leptochela gracilis and Pholis fangi; whereas, in the autumn, Engraulis japonicus and Portunus trituberculatus were dominant species in bag-net catch. Our results will be used to estimate seasonal and annual variation in fisheries resources of Korean coastal waters.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.5
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• pp.804-808
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• 1997

The genetic differentiation and characteristics of two oyster populations (Crassostrea gigas) in Korea were assessed based on the restriction fragment length polymorphisms (RFLP) analysis and the restriction patterns of subcloned mtDNA. The restriction fragments of twenty individuals in West Sea revealed an identical pattern, determined by 8 restriction enzymes. On the other hand, two haplotypes having variation at the HindIII site were shown in the specimens from South Sea; minor haplotypes (4 of 20) were similar to the results obtained from individuals in West Sea while major haplotypes were different from those in West Sea. It was suggested that oysters (C. gigas) of West Sea might have been introduced to South Sea. Each mitochondrial DNA from two oyster populations in Korea and from one in Japan was divided to three parts and subcloned into pUC19 to use in genetic studies effectively. Restriction map was constructed based on the cleavage pattern by multiple restriction enzymes.