• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1243-1245
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• 2003

Mean radiative forcing efficiencies (${\Delta}$F/${\Delta}{\tau}_{0.5}$) over East Asia range from -65 to -95 W m$^{-2}$ at the surface while -20 to -40 W m$^{-2}$ at TOA under clear-sky conditions. These aerosol direct radiative forcings over East Asia are similar to other experimental results for different regions, i.e., the Indian Ocean Experiment (INDOEX) and the Tropospheric Aerosol Radiative Forcing Observational Experiment (TARFOX), from which radiative forcing efficiencies of -75 Wm$^{-2}$ and -70 Wm$^{-2}$ for the Indian Ocean and the East Coast of the United States are reported. Nevertheless, the differences in aerosol parameters and relatively large STD values with regard to spatiotemporal variations suggest that the impact of aerosol on ARF over East Asia is more significant than previously recognized for other regions and should be continuously observed to determine the relation between increasing aerosols and associated radiative forcings in the region.

• Korean Journal of Remote Sensing
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• v.39 no.5_2
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• pp.785-798
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• 2023

Recently, forest fires have become frequent due to climate change, and the size of forest fires is also increasing. Forest fires in Korea continue to cause more than 100 ha of forest fire damage every year. It was found that 90% of the large-scale wildfires that occurred in Gangwon-do over the past five years were concentrated in the east coast area. The east coast area has a climate vulnerable to forest fires such as dry air and intermediate wind, and forest conditions of coniferous forests. In this regard, studies related to various forest fire analysis, such as predicting the risk of forest fires and calculating the risk of forest fires, are being promoted. There are many studies related to risk analysis for forest areas in consideration of weather and forest-related factors, but studies that have conducted risk analysis for forest-friendly areas are still insufficient. Management of forest adjacent areas is important for the protection of human life and property. Forest-adjacent houses and facilities are greatly threatened by forest fires. Therefore, in this study, a grid-based forest fire-related disaster risk map was created using factors affected by forest-neighboring areas using national branch numbers, and differences in risk ratings were compared for forest areas and areas adjacent to forests based on Gangneung forest fire cases.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11a
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• pp.177-184
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• 2003

Numerical simulation on marine wind and sea surface elevation was carried out using both three-dimensional hydrostatic and non-hydrostatic models and a simple oceanic model from 0900 LST, August 13 to 0900 LST, August 15, 1995. As daytime easterly meso-scale sea-breeze from the eastern sea penetrates Kangnung city in the center part as basin and goes up along the slope of Mt. Taegullyang in the west, it confronts synoptic-scale westerly wind blowing over the top of the mountain at the mid of the eastern slope and then the resultant wind produces an upper level westerly return flow toward the East Sea. In a narrow band of weak surface wind within 10km of the coastal sea, wind stress is generally small, less than l${\times}$10E-2 Pa and it reaches 2 ${\times}$ 10E-2 Pa to the 35 km. Positive wind stress curl of 15 $\times$ 10E-5Pa $m^{-1}$ still exists in the same band and corresponds to the ascent of 70 em from the sea level. This is due to the generation of northerly wind driven current with a speed of 11 m $S^{-1}$ along the coast under the influence of south-easterly wind and makes an intrusion of warm waters from the southern sea into the northern coast, such as the East Korea Warm Current. On the other hand, even if nighttime downslope windstorm of 14m/s associated with both mountain wind and land-breeze produces the development of internal gravity waves with a hydraulic jump motion of air near the coastal inland surface, the surface wind in the coastal sea is relatively moderate south-westerly wind, resulting in moderate wind stress. Negative wind stress curl in the coast causes the subsidence of the sea surface of 15 em along the coast and south-westerly coastal surface wind drives alongshore south-easterly wind driven current, opposite to the daytime one. Then, it causes the intrusion of cold waters like the North Korea Cold Current in the northern coastal sea into the narrow band of the southern coastal sea. However, the band of positive wind stress curl at the distance of 30km away from the coast toward further offshore area can also cause the uprising of sea waters and the intrusion of warm waters from the southern sea toward the northern sea (northerly wind driven current), resulting in a counter-clockwise wind driven current. These clockwise and counter-clockwise currents much induce the formation of low clouds containing fog and drizzle in the coastal region.

• Journal of the Korean earth science society
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• v.18 no.6
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• pp.529-539
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• 1997

The circulations and movement of suspended materials by tidal residual current and seasonal surface wind in the Yellow Sea and the East China Sea are investigated by using a 2-dimensional barotropic model and a particle tracing technique. The tidal residual current is relatively strong around the south and west coast of Korea including the Cheju Island and southern coast of China. The current has a maximum speed of 10 cm/s in the vicinity of Cheju Island with a clockwise circulation. General tendency of the current, however, is to flow eastward along the southern coast of Korea. At the east coast of China from Shanghai to Tunghai, it also shows a eastward flow toward the South Sea of Korea. The anticyclonic circulation formed by wind-driven current and southward current prevails along the coast of Korea in the winter season(from October to April) when northerly wind is dominant. In summer(represented by July), however, the cyclonic circulation appears due to the influence of southerly wind. Suspended materials are advected by tidal residual current and wind-driven current. The long period(ten days) displacement by wind-driven current is bigger than that by tidal residual current. However, the tidal residual current would have the more important role for the advection of the suspended material considering longer period more than several months.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.34 no.3
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• pp.287-293
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• 1998

Floating debris was recorded from a training ship, #1 Kwarnksan, of Pukyong National University with about 10 knots speed during March, May and July of 1997. The area sampled is the Southeastern Coast of Korea, divided into 40 unit segments on survey routes. Debris fabrication materials were categorized using the following ; man-made or natural wood items, paper, cardboard, nylon rope, netting, styrofoam and plastics, floating metal and glass containers. All identified items within a $100\;{\pm}\;2\;m$ wide band were recorded but ignored if beyond this boundary.The results of distribution and composition of floating debris in the area as follows:1. The quantities of debris during the duration of survey were distributed from 2~605 items per km2. The most obvious trend is the widespread distribution of all debris. 2. The highest densities of all debris were discovered in the coastal waters of Seoimal lighthouse, the southeastern part of Koje island, next near Nakdong estuaries. Especially styrofoam & plastics were observed in 77.4~87.2% of sampled area, next is wood items, 9.1~ 13.5%. And nylon netting & rope, 3.6%, was the third item of pollutant. Others are very small. 3. Compared with the East Coat of Korea, the quantities of all debus in theSoutheastern Sea are 6 times as large as the East Coast. The survey provides a basis for more detailed survey work in the South Sea. Further surveys are being investigated, and from this it is hoped that a much wider coverage can be achieved, perhaps on all sites of the Coast of Korea and contributed to the removal method, finding of sources, stationary area of debris.

• Animal Systematics, Evolution and Diversity
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• v.8 no.2
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• pp.163-176
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• 1992

Three species of foreign barnacles were found to invade into Korean interitidal seashores: Balanus amphitrite, B. ebumeus and B. improvisus. The southeastern coast of Korea, near Pusan, is the area where all the specimens of three species were discovered and the populations of these species were well establishe. B. amphitrite is the earliest invader(probably invaded around early 1970's) and most widely distributed in Korea. It is now distributed all around Korea, except the Yellow Sea coast, north of Mokpo. B. improvisus has been successful to expand its reange to the northern part of Korean coast of the East Sea, whereas B. eburneus is restricted to the southeastern coast. B. amphitrite is successfully competing with the native barnacle, B. albicostatus, and in several areas where the mixed populations of the two species occur, the latter species is found to excluded. The Yellow Sea coast has not been invaded by the foreign barnacles, the reason of which is not known.

• Korean Journal of Ichthyology
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• v.11 no.2
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• pp.155-162
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• 1999

To study the distribution of larva and juvenile of the sand eel, Ammodytes personatus in the Kangwon coastal, samples were collected by the larva net (RN 80 net) and small drag net at 60 stations from January 1996 to December. Appearance season of larva and juvenile of sand eel was appeared untill the January to June in the Kangwon-do coast, and the densities of them were high in June. Appearance phase, length frequency distribution of larva and juvenile of sand eel were distributed that the average standard length 10.0~30.0mm in the temperature range of $5.0{\sim}6.0^{\circ}C$ at the January to March, and April to June occurred the average standard length 40.0~80.0 mm in the temperature range of $7.2{\sim}12.0^{\circ}C$. It was distributed in southern part of Kangwon-do coast until the February to March 1996. And association of the sand eel migrated to the northern and middle part of Kangwon-do coast at April when surface water temperature was higher than $7.2^{\circ}C$. It was considered that the migration of the abundance larva and juvenile of sand eel in this area is mainly affected by the water temperature.

• Journal of the Korean Society for Railway
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• v.12 no.3
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• pp.427-436
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• 2009

This paper introduced Railway Network Design Problem (RNDP) to provide priority decisions on high-speed railway investment scenarios defined by various network segments and train systems. The RNDP optimizes the objective functions of minimize total travel time. Results show that the priority of high-speed railway investment is found to be East-west, West-coast, and South-coast line respectively. An entirely new line built with 400km/h is found to be the best alternative to East-west line. Regarding West-coast and South-coast line, the combined alternative of upgrading Geolla and Kyeonjon line with 200km/h and building a new line with 400km/h and 350km/h for remains of each line is the best.

• Journal of fish pathology
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• v.26 no.3
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• pp.265-274
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• 2013

The growth, reproduction, gametophyte(G)/tetrasporophyte(T) ratio, and diseases of Chondrus ocellatus populations were examined at 3 sites (Samcheok, Youngduk, Pohang) of East coast and at 2 sites (Hakampo, Manripo) of West coast in between July and August, 2013. Average plant lengths were 6.10~9.69 cm and it was minimum at Manripo and maximum at Pohang population. In general, average plant length and weight of C. ocellatus were greater on East coast than West coast populations. The proportion of vegetative plant was between 26.7~66.7 %, and G/T ratio of total plants including vegetative plants after testing resorcinol method was 3:2 on the East coast where is gametophyte dominant area. However, G/T ratio was 1:1 at Hakampo and 1:2.3 at Manripo representing tetrasporophyte dominance. In the present study, Korean C. ocellatus have various diseases (white colour and green colour), an endophytic alga(Ulvella sp.), and many epiphytic macroalgae and diatoms. Healthy C. ocellatus plants were about 20~40 % in summer population and most of plants had disease. Chondrus ocellatus had a filamentous green alga, endophytic Ulvella sp. which was not identified. The endophyte is easily observed in C. crispus growing in Europe and Canada and it is recognised as a pathogen destroying population and reducing yield of C. crispus. Thus more interest and research on the endophytic algae and disease of C. ocellatus are required.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.6
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• pp.1021-1032
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• 1997

Satellite-tracked drifters deployed in the East Sea since 1991 are used to study the Tsushima Current (TC). It is found that the TC is a steady current with a mean speed of 10 cm/s before it enters the East Sea. Only during the summer, the TC flows along Honshu Island with a mean speed of $30\~40\;cm/s$ and then exits through the Tsugaru Strait. In fall and winter, the TC does not follow the coast along Honshu Island but it enters into the interior of the East Sea before it reaches the Tsugaru Strait. The water that passes the West Channel of the Korea Strait mostly comes from the western East China Sea and spreads into the interior of the East Sea. It also forms the large eddies in the southern East Sea. The outflow through the Tsugaru Strait comes from the interior of the East Sea in all seasons except summer. The mean speed of the Tsugaru Strait outflow is about 60 cm/s. The largest current variability is found in the eastern central area of the East Sea, south of sub-polar front.