• Journal of Navigation and Port Research
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• v.32 no.8
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• pp.637-643
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• 2008

When planning outfall system, the first target cif design is to maximize initial dilution of discharge effluent. To achieve the target effectively, the characteristics of mixing phenomenon between ambient and discharged water should be analyzed. Especially the analysis at the Near-Field-Region(NFR) as initial dilution zone should be preceded. Usually, the initial behavior of effluent through outfall system is rising toward the surface due to mixing with ambient water for heat discharge and sinking toward the bottom due to the difference of density for brine discharge. After mixed with eddies accompanied by the ambient water, the plumes are showing the same density and internal current pattern by advection and diffusion. Until recently, lots of studies are being carried out for the optimum design of outfall system. but it is difficult to find any studies of heat and brine discharge at the same time. Therefore, this study is hoped to provide some basic data for optimum design of outfall system.

• Journal of Ecology and Environment
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• v.35 no.2
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• pp.123-129
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• 2012

Salt marsh is an important transitional zone among terrestrial, riverine, and marine ecosystems and is a productive habitat that interacts extensively with adjacent landscape elements of estuarine and coastal ecosystems. Nowadays, in addition to various human activities, a variety of natural processes induce changes in salt marshes. This study aims to provide background information to restore disturbed salt marshes and to propose their ecological restoration using seed banks. The study area is a prepared area for the Gwangyang Container Port located in the southern Korea. This area was formed by accumulating mud soils dredged from the bottom of the forward sea. This land was created in a serial process of preparing the Gwangyang container port and the salt marsh was passively restored by seeds buried in mud soil dredged from seabed. As a result of stand ordination based on vegetation data collected from the land, stands were arranged according to tolerance to salinity in the order of $Suaeda$ $maritima$, $Salicornia$ $europaea$, and $Phragmites$ $communis$ communities on the Axis 1. Landscape structure of the projected area was analyzed as well. Edges of the projected area were divided from the marginal waterway by the dike. Four types of vegetation appeared on the dike: $Alnus$ $firma$ plantation, $Robinia$ $pseudoacacia$ plantation, $Lespedeza$ $cyrtobotrya$ plantation, and grassland. In the more internal areas, two types of vegetation sequences appeared: $Aster$ $tripolium$ community-$Suaeda$ $glauca$ community-$Salicornia$ $europaea$ community sequence and $Aster$ $tripolium$ community-$Suaeda$ $maritima$ community-$S.$ $europaea$ community sequence. Mixed community showed the highest species diversity (H' = 0.86) and $S.$ $europaea$ community showed the lowest (H' = 0.0). Evenness is the highest in Mixed community (J' = 2.26) and the lowest in $S.$ $maritime-S.$ $europaea$ community (J' = 0.0). Several plant communities were successfully established on the land created by mud soil dredged from the bottom of Gwangyang Bay. Moreover, community diversity in this area approached a similar level with those from other studies involving natural salt marshes. Therefore, restoration effect based on community diversity obtained in our study can be evaluated as a successful achievement. In this respect, although most salt marshes in Korea and other places worldwide have been destroyed or disturbed by excessive land use, feasibility of seed bank as a restoration tool is greatly expected.

• Journal of Korea Port Economic Association
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• v.30 no.2
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• pp.1-23
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• 2014

Although 'the International Ship Registration Act' has been enacted in Korea as of 1997, its effect is still in question to make shipowners and operators flag in or reflag because of insufficient incentives for them. Therefore, 'the Special Law for Jeju Free International City' has been established and the system of 'Special Ship Registration Zone' has also been enforced. Despite this, few studies were carried out to measure the relative importance of factors for Jeju International Ship Register yet. Against this backdrop, the purposes of this study are firstly, to investigate a relative importance of Jeju International Ship Registration System using AHP(Analytic Hierarchy Process) and secondly, to compare the characteristics of Flags of Convenience(FOC) with International Ship Register(ISR) which was adopted by several Far East Asia Countries(e.g., China, Hong Kong, Chinese Taipei and Japan). Moreover, this study aims to compare FOC with ISR in terms of shipping policy, ship management, and expenses and tax policy. In this paper, the factors were constructed with four high levels consisting of twenty one low levels to evaluate Jeju International Ship Register by utilizing Expert's brainstorming and AHP. According to the results, it is critical to expand the exemption and tax-related expenses, and also manage foreign-related systems systemically. This study provides important implications to maintain the tonnage tax system for ships effectively as well as to intensify the competitiveness of Jeju International Ship Register System.

• Korean Chemical Engineering Research
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• v.46 no.4
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• pp.732-738
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• 2008

Simulated moving bed (SMB) process is a continuous chromatographic technology used to separate a large amount of petrochemicals, fine chemicals, pharmaceuticals, and so on, drawing a great attraction of related industries. With the recent development of biotechnology, the SMB process has been adopted for the separation of various useful bio-products. Attempts to understand the separation mechanism of the SMB process in many aspects are reported in many publications. These researches have dealt with the improvement of SMB for easier operation and solving problem in process. The feed mixture fed into the SMB process may be of different concentration batch by batch rather than in uniform concentration. Retention behaviors of feed (psicose (A) and fructose (B) mixture) existing in the SMB unit in dynamic steady-state and feed (psicose (C) and fructose (D) mixture) newly injected into the SMB were analyzed. It was observed that the existing components, (A) and (B), were eluted relatively faster as the injection time of new feed was earlier during the port-switching period. In addition, the components (C) and (D) were eluted earlier as fresh feed was injected earlier in a port-switching time.

• Journal of Digital Convergence
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• v.15 no.7
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• pp.97-109
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• 2017

Domestic vehicle penetration rate is growing at 3% per year, but consumers are increasingly buying used cars due to steady price hikes Nevertheless, the used car export market is expected to decline due to import regulations of major countries and the low grade environment of Used car export complex. Therefore, this study using Fuzzy-AHP was aimed to find operational factors of Used car logistics complex and establish a practical management plan of Used car logistic complex in incheon port. Fuzzy-AHP is the method that can be calculated weight of multi-level criteria and change linguistic ambiguity of human to Fuzzy Number. So it's able to propose the realistic decision making alternatives. As a result of the literacture reviews, present study focused on the analysis of the present situation of the logistics of the used car and the activation of the complex, suggested the activation plan and activation of the logistics complex. In the analysis of operational factors, logistic complex cost factors were found to be the most important factors by recording the weighted value of 0.306 in the above factors. The detailed factors were as follows: rent, accessibility, and logistics site size. It is necessary to compute competitive rent for the highly-advanced used car logistics complex, and to realize the rental support policy and to consider designating the free trade zone. In addition, it is necessary to expand the access infrastructure and secure the scale of the company for overseas buyers, and it is necessary to improve the overall government laws and introduce IT system for the future.

• Journal of Navigation and Port Research
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• v.47 no.1
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• pp.25-36
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• 2023

To limit greenhouse gas emissions from ships, numerous environmental regulations and standards have been taken into effect. As a result, alternative fuels such as liquefied natural gas (LNG), liquefied petroleum gas (LPG), ammonia, and biofuels have been applied to ships. Most of these alternative fuels are low flashpoint fuels in the form of liquefied gas. Their use is predicted to continue to increase. Thus, management regulations for using low flash point fuel as a ship fuel are required. However, they are currently insufficient. In the case of LNG, ISO standards have been prepared in relation to bunkering. The Society for Gas as a Marine Fuel (SGMF), a non-governmental organization (NGO), has also prepared and published a guideline on LNG bunkering. The classification society also requires safety management areas to be designated according to bunkering methods and procedures for safe bunkering. Therefore, it is necessary to establish a procedure for setting a safety management area according to the type of fuel, environmental conditions, and leakage scenarios and verify it with a numerical method. In this study, as a feasibility study for establishing these procedures, application status and standards of the industry were reviewed. Classification guidelines and existing preceding studies were analyzed and investigated. Based on results of this study, a procedure for establishing a safety management area for bunkering in domestic ports of Korea can be prepared.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.28 no.3
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• pp.160-170
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• 2016

In this study, the bottom tracking observation in the tidal entrance within Mokpo coast is performed using ADCP in order to estimate net flux of water mass and tidal prism. First of all, observed rawdata was conducted coordinate rotation considering rotation of the cross-section in order to derive the predominant velocity component. And observed rawdata is converted into Sigma coordinate with normalization and blank zone data near the water surface and bottom is interpolated using von-Karman equation. Net flux of water mass is calculated quantitively from the interpolated data, calculated results show that these represent well characteristic of ebb superiority at Mokpo coast as well as change of net flux of water mass with tide. Also, by complementing the definition of tidal prism proposed in past studies, the definition of tidal prism including tidal condition was re-established. Based on the new definition, tidal prism at a tidal entrance using bottom tracking data with ADCP is estimated quantitively for the first time domestically. The results are compared with those for results of previous study, calculated results were in good agreement with previous studies.

• Journal of the Korean Institute of Navigation
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• v.17 no.4
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• pp.1-21
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• 1993

The purpose of this paper is to search for reasonable and fair principles applicable to the delimitation of the Exclusive Economic Zone(which is called the EEZ, hereinafter) around the Korean Peninsula th-rought the comprehensive study of maritime boundary, which is one of the most important issues in the law of the Sea. So far, the sea has been exploited for activities such as fishery, transport and military stratedy, and en-vironmental policy and so on. From this time on, however, it becomes important to us as the major trea-sure-house of various resources which will be developed and used for diversified purposes. For these rea-sons, nowadays, more and more countries of the world are competing to secure waters as much as possible within their jurisdiction. And the regime of the EEZ was created as a result of this international trend. At last, it has been institutionalized as the 200-mile EEZ of a legal notion in the Convention on the Law of the Sea, which was adopted at the Third United Nations Conference on the Law of the Sea, in Jamaica on December 10, 1982. In adapting to this EEZ institution, Korea is faced with several complicated problems as it is bounded on three sides by the sea and all of its neighboring countries such as the PRC, the DPRK, Japan, Russia etc are less than 400 miles away between opposite countries. Therefore, when trying to delimit the boun-dary for the EEZ, it appears necessary to analyze applicable principles and rules of international law for delimitation mainly through the Convention on the Law of the Sea, and studies the trends of actual State practices and recent international precedents. It is hoped that such knowledge will enable Korea to secure sufficient resources and other sovereign rights without conflicting with the neighboring countries concer-ned. For the achievement of the above mentioned object. I analyzed the necessities of the establishment of the EEZ in Korea, the difficulties and practices of Korea's neighbors, and the changes and forthcoming trends in Korea's relations with its neighbors concerned on the basis of the general explanation of the EEZ regime. In conclusion, it is my opinion that for the establishment of the EEZ delimitation which neighbors around the Korean Peninsula should be applied reasonable and equitable principles considering the rele-vant circumstances which characterize the area definitely as well as the UN Convention on the Law of the Sea, 1982.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.18 no.2
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• pp.124-136
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• 2006

The change pattern of the sediment grain size distribution information (median grain size(D50)) due to some gridding method and sampling density is analyzed with reference to the grid information estimated by the 90 sediment samples which was collected in the coastal water off the Baengnyeongdo Island, in June 2004. The standard deviation of absolute deviation (AD) estimated the selected gridding method shows 8.0 ${\mu}m$ at June, 2004 and 10 ${\mu}m$ November, 2004. The estimated statistical information of absolute deviation in comparison with the grid information of reference and changed sampling density shows that the AD mean error trends increase as the number of samples decrease. The AD mean error is below 10% in the case of the information estimation using 50-sample with reference to the 90-sample information. In this case, the sampling density is suggested as about 9 sediment samples per $km^2$, at coastal zone in Yoggipo port in the condition of the study area is 5.9 $km^2$.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.6C
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• pp.339-347
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• 2008

The penetration of the probe produces the excess pore pressure due to the disturbance. The objective of this study is to evaluate the disturbance zone by using the dissipation of the excess pore water pressure, which was generated due to the penetration of the penetrometer with different size. The CPT, DMT and FVP (Field Velocity Probe) are adopted for in-situ tests. The tests are carried out in the construction site of north container pier of Busan new port, Korea where is accelerating the consolidation settlement using plastic board drains (PBD) and surcharges by crushed gravels. The coefficient of consolidation $(C_h)$ and soil properties are deduced by the laboratory test. The in-site tests are performed after the predrilling the surcharge zone at the point of 90% degree of consolidation. To minimize the penetration effect, the horizontal distance between penetration tests is 3m, the change of the pore pressure is monitored at the fixed depth of 24m. The coefficient of consolidation $(C_h)$ and the $t_{50}s$ are calculated based on the laboratory test and the in-situ data, respectively. The equvalent radi based on the $t_{50}$ shows that the FVP and the DMT produce the smallest and the greatest equivalent radi, respectively.