• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.6
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• pp.685-695
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• 2019

To assess the state of Todarodes pacificus fisheries, we examined changes in major fishing and ecological characteristics by comparing jigging fishery data between high (HCLP, 1996-2000) and low (LCLP, 2013-2017) catch level periods. The peak catch occurred in October during the HCLP compared with December during the LCLP. The average catch per unit effort was higher during the HCLP (1.3 tons/jigging vessel) than LCLP (1.0 ton/jigging vessel). During the HCLP, fishing grounds were highly concentrated in the southwestern East Sea and Yamato bank, whereas during the LCLP, the distribution of grounds extended to the South Sea, West Sea, and northern East Sea (near Russian waters) at a low density. Water temperatures in the main fishing ground in the southwestern East Sea were higher at 0, 50, and 100 m depths during the LCLP than HCLP. Meanwhile, the average mantle length of catches decreased from 23.5 cm during the HCLP to 22.21 cm during the LCLP. The mantle length at 50% maturity also decreased between the two periods from 22.06 (HCLP) to 18.77 cm (LCLP). These findings will help guide future management strategies for T. pacificus.

• Korean Journal of Environmental Agriculture
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• v.19 no.5
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• pp.382-393
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• 2000

The principal indicators contributing to water qualities was screened by factor analyses, based on the monitored chemical parameters of water quality for various water resources from 1995 to 1999 in the small agricultural catchments of the Han River Basin. Water samples of streams, groundwaters, and reservoirs were taken four times a year from upper (Daegwanryong), middle (Dunnae and Chunchon) and lower (Guri) reaches of Han River Basin. In these areas, the respective type of farming practiced was alpine agriculture and livestocks raising, typical upland and paddy cultivation, and intensive cropping in the plastic film house. Water quality was monitored for twenty-one water quality parameters, including pH, EC, SS, T-N, T-P, COD, cations, anions, and heavy metals. pH, EC and COD of the stream waters were suitable for the Korea irrigation water quality guidelines. However, T-N and T-P concentrations of water samples in four catchments far exceeded the irrigation water guideline. Concentrations of canons and heavy metals in Wangsuk stream in Guri area were higher than those in streams in other areas. Factor analysis revealed that significant correlation was observed for 81 pairs out of 231 water quality indicators of stream water among the $21\;{\times}\;21$ cross correlation matrix of stream water quality indicators. The first factor accounted for 27.01% of the total variation in stream water quality indicators, and high positive factor loadings were shown on EC, K, Na, $NH_4\;^+-N$, $PO_4\;^{3-}$, $SO_4\;^{2-}$, and COD. Fifty-three water quality indicator pairs were significant out of 190 ground water quality parameters. The first factor accounted for 28.54% of the total variation in ground water quality indicators, and high loadings were revealed on EC, Ca, Mg, K, Na, $NH_4\;^+-N$, and $SO_4$. Twenty-nine pairs of reservoir water quality indicators were significant out of 66 pairs. The first factor accounted for 37.06% of the total variation in reservoir water quality indicators, and high loadings were shown on EC, Mg, K, Na, SS, T-P, Cl, and COD. These results demonstrate that EC was the first factor contributing to water quality.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.4
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• pp.341-348
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• 1983

The Relationship between the distribution of the fishing grounds of anchovy and the oceanographic conditions in the Korean Waters are investigated by using the data of the catch of anchovy by the gill net fishery (Fisheries Research and Development Agency, 1969-1982) and the oceanographic observation data (Fisheries Research and Development Agency, 1979). The main fishing ground of anchovy by the gill net fishery was five fishing areas located in the adjacent seas of Sockcho, Kuryong-po, Kijang, Keoje island and Chungmu, the area of which occupies no more than $20\%$ of all fishing grounds, and it appeared that about $80\%$ of mean catches of fourteen years was concentrated in this area. The main fishing periods were from April to June and October to November. The coefficient of variation of the catch for the main fishing ground were from 0.3 to 0.6 and the condition of all fishing ground was generally stable. The mean CPUE was 81.2 kg/set at the main fishing ground. The annual mean catch of anchovy by the gill net was the smallest in February and the largest in May through a year. It was found that the fluctuation is related to the expansion and reduction of the isothermal line of $10^{\circ}C$.

• Strategy21
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• s.31
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• pp.27-56
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• 2013

The United Nations Command (UNC) and the communist North failed to reach an agreement on where the maritime demarcation line should be drawn in the process of signing a truce after the Korean War because of the starkly different positions on the boundary of their territorial waters. As a result, the Armistice Treaty was signed on July 1953 without clarification about the maritime border. In the following month, Commander of the UNC unilaterally declared the Northern Limit Line (NLL) as a complementing measure to the Armistice. Referring to this, North Korea and its followers in South Korea wrongfully argue that the NLL is a "ghost line" that was established not based on the international law. However, one should note that the waters south of the NLL has always been under South Korea's jurisdiction since Korea's independence from Japan on August 15, 1945. There is no need to ask North Korea's approval for declaring the territorial waters that had already been under our sovereign jurisdiction. We do not need North Korea's approval just as we do not need Japan's approval with regard to our sovereign right over Dokdo. The legal status of the NLL may be explained with the following three characteristics. First, the NLL is a de facto maritime borderline that defines the territorial waters under the respective jurisdiction of the two divided countries. Second, the NLL in the West Sea also serves as a de facto military demarcation line at sea that can be likened to the border on the ground. Third, as a contacting line where the sea areas controlled by the two Koreas meet, the NLL is a maritime non-aggression line that was established on the legal basis of the 'acquiescence' element stipulated by the Inter-Korea Basic Agreement (article 11) and the Supplement on the Non-aggression principle (article 10). Particularly from the perspective of the domestic law, the NLL should be understood as a boundary defining areas controlled by temporarily divided states (not two different states) because the problem exists between a legitimate central government (South Korea) and an anti-government group (North Korea). In this sense, the NLL problem should be viewed not in terms of territorial preservation or expansion. Rather, it should be understood as a matter of national identity related to territorial sovereignty and national pride. North Korea's continuous efforts to problematize the NLL may be part of its strategy to nullify the Armistice Treaty. In other words, North Korea tries to take away the basis of the NLL by abrogating the Armistice Treaty and creating a condition in which the United Nations Command can be dissolved. By doing so, North Korea may be able to start the process for the peace treaty with the United States and reestablish a maritime line of its interest. So, North Korea's rationale behind making the NLL a disputed line is to deny the effectiveness of the NLL and ask for the establishment of a new legal boundary. Such an effort should be understood as part of a strategy to make the NLL question a political and military dispute (the similar motivation can be found in Japan's effort to make Dokdo a disputed Island). Therefore, the South Korean government should not accommodate such hidden intentions and strategy of North Korea. The NLL has been the de facto maritime border (that defines our territorial waters) and military demarcation line at sea that we have defended with a lot of sacrifice for the last sixty years. This is the line that our government and the military must defend in the future as we have done so far. Our commitment to the defense of the NLL is not only a matter of national policy protecting territorial sovereignty and jurisdiction; it is also our responsibility for those who were fallen while defending the North-Western Islands and the NLL.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.6
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• pp.859-868
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• 1998

In order to investigate the relation between the marine environmental characteristics and the change of the catch in set net, the marine environment properties were analyzed by temperature and salinity observed in the western coastal area of Cheju Island from 1995 to 1996 and the results are as follows 1) Main axis of Tsushima Current appeared in the western coastal area of Cheju Island was off 2$\~$3 miles from November to May. Therefore the waters of high temperature over $14^{\circ}C$ and high salinity from $34.40\%_{\circ}$ to $34.60\%_{\circ}$ were distributed homogeneously from surface to bottom in this time. But China Coastal Waters of low salinity appeared in the Cheju Strait from June to October, surface waters became of high temperature and low salinity, and middle and bottom waters became of the temperature from 11 to $14^{\circ}C$ and the salinity over $33.50\%_{\circ}$ and then vertically sharp thermocline and halocline are formed in the western coastal area of Cheju Island. In summer, the water temperature and salinity of the surface waters in wstern coastal area of Cheju Island were lower and higher respectively than that in middle area of the Cheju Strait and the temperature and salinity of the bottom waters in this area were higher and lower, respectively than that in middle area of the Cheju Strait. Such a distribution shows a tidal front in this coastal area. On the whole year, surface temperature and salinity were from 14 to $23^{\circ}C$ and from 30.60 to $34.60\%_{\circ}$, respectively, and annual fluctuation range of temperature and salinity was within $9^{\circ}C$ and $4.00\%_{\circ}$, respectively, Thus, annual fluctuation range in this area is much narrower than that in the Cheju Strait. In bottom water, temperature ranges from 14 to $20^{\circ}C$ through the year. Thus, the fluctuation range of temperature is narrow. The low temperature of from $11^{\circ}C$ to $13^{\circ}C$ appeared in the west enterance of Cheju Strait was not shown in this coastal area. 2) The salinity of bottom water was from $33.60\%_{\circ}$ to $34.40\%_{\circ}$ in 1995, while low salinity wale. below $32.00\%_{\circ}$ appeared all depth from June in 1996. Thus, the variation of hydrographic conditions in this area is narrow in winter, and wide in summer due to the influence of China Coastal Waters. 3) In summer, surface cold water, local eddy and fronts of temperature and salinity were showed within 2 mile from the west coast of the Cheju Island due to vertical mixing by tidal current. Especially, temperature and salinity of bottom water are changed with the change of depth around Biyang-Do. Thus, the front of temperature and salinity appeared clearly between shallow area with the depth of under 10 m and deep area with of the depth of more than 50m. Surface water in outside area where high temperature and low salinity water appear intrudes between Worlreong-Ri and Geumreung-Ri. Thus, the front of temperature and salinity was made along the line that connects from this coast to Biyang-Do, The temperature of the bottom water is $2^{\circ}C$ to $4^{\circ}C$ lower than that of the surface water and its salinity is $0.02\%_{\circ}$ to $0.08\%_{\circ}$ higher than that of the surface water even in shallow area.

• Spatial Information Research
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• v.15 no.1
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• pp.25-33
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• 2007

The purpose of this study is to assess spatio-temporal variation of Imha Dam water quality according to suspended sediment algorithm using Landsat and SPOT 5 data. In order to learn synchronous suspended sediment concentrations(SSC) in Imha Dam waters, the satellite remote sensing data are analyzed. The key procedure of this research is that we should know the relationships between suspended sediment concentrations and satellite-detected reflectance. However, the SSC algorithm has the limitation that it must be compared calculated SSC with synchronous ground-truth data in the Dam water. Based upon the linear response from satellite-detected reflectance, SSC algorithm validated an efficient algorithm to estimate proportional factor and then derived an empirical equation far SSC estimations.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2009.11a
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• pp.55-58
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• 2009

Traditional pile-buildings in Southeast Asia has high utility. Their floors are lifted above the ground to stave off humidity in the house, increase the amenity and hygienic condition, fend off fierce animals or harmful animals like rat, and protect the house from being submerged in flood waters. Such traditional pile-buildings have Austronesian saddle-backed roof commonly, and are built through various techniques such as joining and mortising, without use of nails. The roof has a considerably large proportional appearance, and for this formal characteristics, the roof is symbolized as boat on occasions. The roof has dual structures or is lifted in some cases to facilitate the ventilation, and the wall is formed to maximize the ventilation. This housing types the hierarchy of foundation, housing space, and roof, which implies religious symbolism that human is above animal and God is above human. However, housing types in Southeast Asia have very different detailed form and culture, depending on the ethnic and religious characteristics. As explained above, this study examines the common aspects and diversity based on the form and culture of traditional housing of Southeast Asia and provides useful basic academic data.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.26 no.4
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• pp.317-325
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• 1990

The attraction activity of the natural baits for sea eels(Astroconger myriaster) was surveyed by using fishing traps in the 3 different fishing ground of southern coastal waters of Korea. Twenty four different baits were experimented and weight for each bait was 50g, the optimal minimum weight owing to our preliminary test. Among the above 24 baits, anchovy(Engraulis japonica), sardine(Sardinops melanosticta), or marine worms(Neanthes japonica)were most effective. In case of sardine bait, the body showed higher attraction activity than the head or viscera and the builded juice of anchovy or sardine showed higher attraction activity than spoiled one.

• Journal of the Korean Society of Clothing and Textiles
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• v.16 no.1 s.41
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• pp.111-122
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• 1992

Studying the dress style of the Buddhist Goddess of Mercy SU WOL KWAN EUM DO (Drawings on the Buddhist Goddess of Mercy who is watching the Moon reflected in the still water), it is composed of a splendid, jewel crown with five colors, a light and flimsy, non-colored veil with many kinds of gold·plated patterns. This gold·plated carapace figures on a scarlet ground are drawn on the veil and the oval-type flower figures mixed with a scarlet lotus blossom ard arranged. An arabesque pattern of BOSANGHWA (an imaginary, Buddhistic flower figure) is mainly used for both line decorations and necklace. Like this, various kinds and types of figures are in harmony in spite of many changes in figure design. The SU WOL KWAN EUM DO in Koryo dynasty is full of colorful, subtle, harmonious figures which are unique style, which cannot be found in japan, China, and so on. In other words, most of most of dress patterns which are shown in SU WOL KWAN EUM DO are China ink paintings with mountains and waters as its setting. In case of color painting, figure designs are seldom used. The dress pattern in SU WOL KWAN EUM DO of koryo dynasty is characteristic of its variety and magnificent colors.

• Environmental Engineering Research
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• v.12 no.4
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• pp.157-175
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• 2007

The membrane biofilm reactor (MBfR) creates a natural partnership of a membrane and biofilm, because a gas-transfer membrane delivers a gaseous substrate to the biofilm that grows on the membrane's outer wall. $O_2$-based MBfRs (called membrane aerated biofilm reactors, or MABRs) have existed for much longer than $H_2$-based MBfRs, but the $O_2$-based MBfR is a versatile platform for reducing oxidized contaminants in many water-treatment settings: drinking water, ground water, wastewater, and agricultural drainage. Extensive bench-scale experimentation has proven that the $H_2$-based MBfR can reduce many oxidized contaminant to harmless or easily removed forms: e.g., ${NO_3}^-$ to $N_2$, ${ClO_4}^-$ to $H_2O$ and $Cl^-$, ${SeO_4}^{2-}$ to $Se^0$, and trichloroethene (TCE) to ethene and $Cl^-$. The MBfR has been tested at the pilot scale for ${NO_3}^-$ and ${ClO_4}^-$ and is now entering field-testing for many of the oxidized contaminants alone or in mixtures. For the MBfR to attain its full promise, several issues must be addressed by bench and field research: understanding interactions with mixtures of oxidized contaminants, treating waters with a high TDS concentration, developing modules that can be used in situ to augment pre-denitrification of wastewater, and keeping the capital costs low.