• Korean Journal of Ecology and Environment
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• v.44 no.4
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• pp.327-336
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• 2011

Temporal and spatial variations of primary productivity were investigated in the estuary of Youngsan River and Mokpo coastal areas in 2009. After heavy rain, concentrations of ammonium, phosphate, and silicate increased at six stations in August. The torrential rainfall may cause an increase in nutrient concentrations during summer. There is no limitation of nutrients (except for February at the mid-Youngsan estuarine region YS2) but a potential phosphate limitation was apparent at all stations. Silicate depletion was observed at YS2 in February due to a massive diatom bloom. The trophic status of the Youngsan estuary and Mokpo coastal areas were inferred from an assessment of the primary productivity. In February and May, YS1 (upper Youngsan estuary site) and YS2, YS3 (near the Youngsan river estuary barrage), MP1 (upper Mokpo coastal region site) were appropriately assigned to the mesotrophic category. MP2 (mid-Mokpo coastal region site) and MP3 (outer site of Mokpo coastal region) were assigned to the oligotrophic category. All stations were classified to the oligotrophic status in November. In August, after heavy rain, Youngsan estuary stations maintained mesotrophic status. On the other hand, MP1 and MP2 were classified in the eutrophic category and MP3 to mesotrophic status. In particular, primary productivities of MP1 and MP2 were 9 and 7 times higher respectively than the standard of eutrophic status ($1,000-mgC\;m^{-2}d^{-1}$). These results suggest that a massive freshwater discharge from the Youngsan River estuary should be considered a main factor in the occurrence of phytoplankton bloom in Mokpo coastal areas during summer. Seasonal variations of primary productivity are closely related with depth-integrated Chl. a.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.27 no.3
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• pp.311-321
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• 2009

The Nation Geodetic Reference System which presents a consistent location standard used in creating a map or developing national land is defined and managed by the law in a nation. Each nation had used its own geodetic system created by astronomical surveying until recently, when Geodetic Reference System(World Geodetic Reference System) has been developed and used to progress in space and satellite geodetic technologies. Korea also amended its geodetic law in December 2001, converting its national geodetic system whose reference an oval figure is Bessel ellipsoid into the World Geodetic Reference System which uses GRS80 ellipsoid as reference ellipsoid. Accordingly, the National Geography Information Institute improved law and systems related to the change for the effective conversion from its national geodetic system into the World Geodetic Reference System. In addition National geographic information institute of the results of various studies is drawn to the World Geodetic Reference System for switching technology-met some of the institutional foundation Despite of accordance with formalities, National geographic information institute, Ministry of Land, Transport and Maritime Affairs and some local government of the World Geodetic Reference System, and local government has or has not spread in public institutions. Therefore, in order to promote the switch to the World Geodetic Reference System, it is required to analyze current technical and institutional problems and obstacles of the switch to the World Geodetic Reference System and to present the resolutions and to establish policy to achieve them. Accordingly, for the promotion of the switch to the World Geodetic Reference System, this study analyzed the results of previous studies, the current state of the switch to the World Geodetic Reference System and the problems of the switch, and then offered technological and institutional supplements. Furthermore, it standardized the subject and type of the conversion, defined the scope of the tasks of the National Geographic Information Institute and its related organizations, and presented the policy direction for the overall use of the World Geodetic Reference System by 2010.

• Journal of the Korean Society for Marine Environment & Energy
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• v.13 no.3
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• pp.135-150
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• 2010

At the Intergovernmental Meeting held in 1972, the London Convention was adopted to prevent marine pollution from dumping of wastes and other matter. After that, at the special meeting held at the Headquarters of the International Maritime Organization in 1996, the London Convention was revised to consider advances in technology of treatment and disposal of wastes and to reflect changes in understanding of marine environment and then the London Protocol was concluded. The London Protocol states more concrete management system for ocean dumping than the London Convention and also provides that the Meeting of Contracting Parties shall establish those procedures and mechanisms necessary to assess and promote compliance with the Protocol. With the London Protocol in force since 24 March 2006, the Meeting of Contracting Parties adopted the 'Compliance Procedures and Mechanisms (CPM) pursuant to Article 11 of the 1996 Protocol to the London Convention 1972' and established the Compliance Group in 2007. According to the CPM, members of the Compliance Group shall be nominated by Contracting Parties, based on equitable and balanced geographic representation of the five Regional Groups of the United Nations, and elected by the Meeting of Contracting Parties. In 2009, the Republic of Korea nominated a member of the Compliance Group to be subsequently elected by the Meeting of Contracting Parties with the approval of other states in Asia Group. Through the United Nations Regional Group System based on geographical identity or political affinity, Contracting Parties to the London Protocol are expected to form a voting bloc or to exchange information in meetings on the London Protocol. In this sense, it is noteworthy that the London Protocol introduced marine environmental management system for comprehensive prohibition of ocean dumping with exception of the so-called 'reverse-list' which had been earlier adopted by the 'Convention for the Protection of the Marine Environment of the North-East Atlantic, 1992 (OSPAR)' whose contracting parties belonged to Western European and Other States Group. In recent years, the jurisdiction of London Protocol has been extended to protect and preserve the marine environment from all sources of pollution. This will make the United Nations Regional Group System play more important roles in the activities associated with the London Protocol. For this reason, this article has considered characteristics of the United Nations Regional Group System and has analyzed influences of this Regional Group System in meetings on the London Protocol. This could provide preliminary information for the Republic of Korea to give due consideration to the United Nations Regional Group System on the activities associated with the London Protocol.

• Journal of the Korean Society for Marine Environment & Energy
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• v.9 no.1
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• pp.45-54
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• 2006

The study was to review methods by which a ship can unfold and tow an oil boom by attaching the opening apparatus to an oil boom through experiments. The shape and dimension of the opening apparatus were designed with the measurement value of the towing tension load of the oil boom and the dimension of winch drum of the oil boom installed in the ship considered. For the field experiment to identify the performance of the opening apparatus, opening apparatuses were prepared to have the dimension of $3.0m^2$ and $6.0m^2$ which is 91% and 75% of the calculation value for type B and C respectively. As a result, T(kg), the value of tension in type B oil boom according to the towing speed(v) change when two ships are towed together were proved to be $T=920v^{1.1}\;and\;T=500v^{0.9}$ in case the distance is 100 m and 50 m. Based on the result, the dimension of the opening apparatus for type B and C oil boom was calculated as $3.3m^2$ and $8.0m^2$ respectively. When unfolding and towing by attaching the opening apparatus and 200 m of towing line at both ends of type B and type C oil boom, the maximum width of the opening apparatus was shown as 114 m and 95 m in average(width of opening/total length of oil boom: 33% and 57%) in the towing speed of 1.5 kt. It was evaluated that the opening apparatus could concentrate the spilled oil in a good performance. However as far as the increase rate of oil boom opening width according to the length of the towing line is debatable, the increase rate is remarkably reduced when it is lengthened from 100 m to 150 m and to 200 m although it showed extreme increase of 31% and 40% when the length of the towing line was changed from 50 m to 100 m. Therefore, it is inferred that the towing line should be maintained more or less 100 m to get good spread efficiency of the opening apparatus. Additionally, if the towing speed is faster than 1.5 kt, the opening width was narrowed because of the reduced spread efficiency and the shape of the oil boom can be unstable because of the partial sinking of the oil boom, run over waves, or flap of skirt. Thus the reasonable towing speed can be within 1.5 kt for the operation of the opening apparatus.

• Journal of the Korean Society for Marine Environment & Energy
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• v.9 no.4
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• pp.243-252
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• 2006

Influence of the increasing carbon dioxide concentration in seawater on various marine organisms is assessed in this article with regard to the impacts of anthropogenic $CO_2$ introduced into surface or deep oceans. Recent proposals to sequester $CO_2$ in deep oceans arouse the concerns of adverse effects of increased $CO_2$ concentration on deep-sea organisms. Atmospheric introduction of $CO_2$ into the ocean can also acidify the surface water, thereby the population of some sensitive organisms including coral reefs, cocolithophorids and sea urchins will be reduced considerably in near future (e.g. in 2100 unless the increasing trend of $CO_2$ emission is actively regulated). We exposed bioluminescent bacteria and benthic amphipods to varying concentrations of $CO_2$ and also pH for a short period. The ${\sim}l.5$ unit decrease of pH adversely affected test organisms. However, amphipods were not influenced by decreasing pH when HCl was used for the seawater acidification. In this article, we reviewed the biological adverse effects of $CO_2$ on various marine organisms studied so for. Theses results will be useful to predict the potential risks of the increase of $CO_2$ concentrations in seawater due to the increase of atmospheric $CO_2$ emission and/or sequestration of $CO_2$ in deep oceans.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.2
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• pp.163-169
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• 2005

Photocatalytic oxidation of Cu(II)-EDTA has been studied using solar/$TiO_2$ photocatalysis as an energy source. Photocatalysis efficiency on the treatment of Cu(II)-EDTA was investigated using different types of solar collectors as well as by variation of the angles of solar collector solar light intensities, flow rates, and areas of solar collector. effect of $H_2O_2$ and types of $TiO_2$ catalyst on the treatment of Cu(II)-EDTA was also investigated. Removal of Cu(II) and DOC was favorable with a hemispherical collector than with a flat collector Removal of Cu(II) and DOC increased with increasing angles of solar collector up to $38^{\circ}$. Slurry type $TiO_2$ showed four-times higher removal efficiency than immobilized type $TiO_2$. Removal of both Cu(II) and DOC at a clear sky of solar light intensity ranging from 0.372 to $2.265\;mW/cm^2$ was greater than removal at a cloudy day of solar light intensity ranging from 0.038 to $1.129\;mW/cm^2$. From the result of this research that the removal efficiency of Cu(II) and DOC increased as the solar light intensity increased, it can be inferred that quantum yield in the destruction of Cu(II)-EDTA may directly related with the solar light intensity. Removal of Cu(II) increased as increasing the area of solar collector and was similar at lower flow rates white removal of Cu(II) was interfered at higher flow rates. When immobilized $TiO_2$ was used, removal efficiency of Cu(II) increased in the presence of $H_2O_2$ while negligible effect was found in the use of $TiO_2$ slurry.

• Journal of the Korean Chemical Society
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• v.40 no.7
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• pp.474-482
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• 1996

Two crystal structures of the vacuum dehydrated $Ag^+$-exchanged zeolite X have been determined by single-crystal X-ray diffraction techniques in the cubic space group Fd3 at 21(1)$^{\circ}C$ (a=24.922(1)${\AA}$ and a=24.901(1)${\AA}$, respectively). Each crystal was ion exchanged in flowing streams of aqueous $AgNO_3$ for three days. The first crystal was dehydrated at 300$^{\circ}C$ and $2{\times}10^{-6$torr for two days. The second crystal was similarly dehydrated at 350$^{\circ}C$. Their structures were refined to the final error indices, $R_1=0.095\;and\;R_2=0.092$ with 227 reflections, and $R_1=0.096\;and\;R_2=0.087$ with 334 reflections, respectively, for which I > 3${\sigma}$(I). In the first crystal, Ag species are found at five different crystallographic sites: sixteen $Ag^+$ ions fill the site I, the center of the double 6-ring, thirty-two Ag0 atoms fill the I' site in the sodalite cavities opposite double six-rings, seventeen $Ag^+$ ions lie at the 32-fold site II' inside the sodalite cavity at the single six-oxygen ring in the supercage, fifteen Ag+ ions lie at the 32-fold site II, in the supercage, and the remaining twelve $Ag^+$ ions lie at site III' in the supercage at a little off two-fold axes. In the second crystal, all Ag species are located similarly as crystal 1; 16 at site I, 28 at site I', 16 at site II, 16 at site II', 6 at site III and 6 at site III'. Total 88 silver species were found per unit cell. The remaining four Ag atoms were migrated out of the zeolite framework to form small silver crystallites on the surface of the zeolite single crystal. In the first structure, the numbers of Ag atoms per unit cell are approximately 32.0 and these may form tetrahedral $Ag_4$ clusters at the centers of the sodalite cavities. The probable four-atom cluster is stabilized by coordination to two $Ag^+$ ions. The Ag-Ag distance in the cluster, ca. 3.05 ${\AA}$, is a little longer than 2.89 ${\AA}$, Ag-Ag distance in silver metal. At least two six-ring $Ag^+$ ions on sodalite cavity (site II') must necessarily approach this cluster and this cluster may be viewed as a distorted octahedral silver cluster, (Ag6)2+.

• Journal of the Korean Institute of Gas
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• v.22 no.1
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• pp.37-44
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• 2018

As the international Maritime Organization is tightening up the emission regulation vessel, many countries and companies are pushing ahead the LNG fuel as one of long term solution for emission problems of ship. as a study on the way to conduct business for LNG bunkering around the world, this study was analyzed in view-point of business models focused on major countries such as Japan, China, Singapore, Europe and United States. The results of this study are as follows. China first established a nation-centered LNG bunkering policy. And then, the state and the energy company have been cooperating and carrying on LNG bunkering business for LNG fueled ships. Some countries in Europe and United States are in the process of LNG bunkering business mainly with private company. To obtain cheaper LNG fuel than bunker-C, the private company has a business model of LNG bunkering on their own LNG fueled ships, while securing LNG with high price competitiveness through partnership with middle class operators such us LNG terminal and natural gas liquefaction plant. Also, the LNG bunkering business around the world is focused on private companies rather than public corporations, but it was going to be focused on large energy companies because the initial cost required to build LNG bunkering infrastructure. Three models (TOTE model, Shell model, ENGIE model) of LNG bun kering business are currently being developed. It has been found that the way in which LNG bunkering business is implemented by different countries is applied differently according to the enterprise and national policy.

• Journal of the Korean Society for Marine Environment & Energy
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• v.8 no.4
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• pp.227-235
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• 2005

This study aimed at suggesting management policy directions for the uninhabited islands of Korea which are national land resources with economic potential for tourism and development and strategic value for boundary delineation of territorial waters and exclusive economic zone as well as their unique ecological status. Review of existing management arrangements related to the uninhabited islands revealed six management issues to be addressed: insufficient data and their low reliability, lack of management policy directions, increase in ecosystem deterioration and perturbation by human activities, lack of policy measures for meeting utilization and development demands, weak management base with insufficient personnel and budget, and legal measures not taking Into account their unique ecological and socioeconomic characteristics. The management policy directions to improve the management of the uninhabited islands of Korea include management directions and strategies, and suggestions for legal improvement. Considering the unique ecological value of the uninhabited islands, management directions suggested are anti-degradation in which current and future demands for their utilization and development do not degrade the ecological potential of the uninhabited islands and integration in which land and sea areas are managed as an integrated management unit. Four strategies proposed to follow the management directions are enhancement of the knowledge base through a comprehensive survey, development and legislation of guidelines for the rational management of utilization and development demands, establishment of the comprehensive island debris collection and disposal system, and enhancement of management capacity. Legal improvement for the effective implementation of the management policy directions should include comprehensive uninhabited islands survey, legal utilization restraints and management guidelines based on classification of the islands, management boundary, and improvement of regulations on designated islands.

• Journal of Korea Port Economic Association
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• v.25 no.3
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• pp.139-164
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• 2009

The purpose of this paper is to investigate the value chain efficiency of Korean port investment by using the newly developed multi-year and multi-stage value chain efficiency model of DEA(Data Envelopment Analysis). Inputs[port investment amount, cargo handling capacity, and berthing capacity], and outputs[cargo handling amount, number of ship calls, revenue, and score of customer service satisfaction] are used during 14 years(1994-2007) for 20 Korean seaports by using two kinds of DEA models. Empirical main results are as follows: First, Model 1 shows that the ranking order of multi-stage value chain efficiency is Stage 2, Stage 3-1, Stage 1, and Stage 3-2. And according to the value chain average efficiency scores, ranking order is stages 2, 1, 3-1, and 3-2. In Model 2, 3(Incheon, Mogpo, and Jeju) out of 9 ports show the ranking order of Stages 2, 3-2, 3-1, and 1. And value chain average efficiency scores rank in order of Stages 2, 3-2, 3-1, and 1. Second, the difference among the value chain efficiency scores of each stage comes from the efficiency deterioration of all ports except Stages 2 and 1 in Model 1. In Model 2, value chain efficiency scores among the Stages 3-1, 3-2 compared to Stage 1 were deteriorated. The main policy implication based on the findings of this study is that the manager of port investment and management of Ministry of Land, Transport and Maritime Affairs in Korea should introduce the multi-year, multi-stage value chain efficiency method for deciding the port investment amount and evaluating the effect of port investment after considering the empirical results of this paper carefully.