• Journal of Marine Life Science
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• v.2 no.2
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• pp.56-61
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• 2017

This study examined the environmental characteristics of shore pollution sources in the southern part of the Sinan, Jangsando area in the West Coast of Korea. A shoreline survey of the watershed was conducted to identify the pollution sources and measure the water discharge rate and microbial hygiene of water and finally estimate the possible impact area of pollution. Forty five of pollution sources in total were identified and they were grouped into sewage (33), agriculture waste water (1) and waste water from inland fish farm (11). Nine among them were discharged into the seawater and discharge volume was 72,857~281,250 l/min. Fecal coliforms of St. 72 (sewage) and St. 74 (shrimp farm) were 490 MPN/100 ml and 49 MPN/100 ml and the impact zones of the pollution were 4,389 m and 1,900 m respectively.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.36 no.1
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• pp.20-36
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• 2024

In this study, probabilistic models for the wave- and lifting forces were derived directly from long-term in-situ wave data embedding the Korean marine environment characteristics varying from sea to sea based on the Three-Parameter Weibull distribution. Korean marine environment characteristics varying from sea to sea carved out their presence on the probability coefficients of probabilistic models for wave- and lifting forces. Energetic wave conditions along the southern coast of Korea distinguish themselves from the others with a relatively large scale coefficient, small location coefficient, and shape coefficient around 1.3. On the other hand, mild marine environment along the western coast has a small variability, leading to small scale-coefficient, large location coefficient and shape coefficient around 2.0. In the sea off Mokpo, near the boundary between the South- and West Seas, marine environment was characterized by small scale-coefficient, large location coefficient, and shape coefficient around 1.2, implying that marine environments characteristics of the South-and West Sea coexist in the sea off Mokpo.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.32 no.3
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• pp.170-179
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• 2020

Tidal asymmetry would occur owing to shallow water tides at the Western Coast of macro tidal area. Especially, as ebb dominance of Mokpo coastal zone is known as the most prominent in Korea, it had been studied by domestic researchers. The cause of ebb dominance in Mokpo area is considered due to extensive inter-tidal zone in Muan Bay, and this has been studied based on amplification ratio, relative phase and skewness of tide/tidal flow curves in order to analyze qualitative tidal asymmetry. Furthermore, it was possible to figure out tidal characteristics with the difference of tidal amplitude and phase with Mokpo Harbor by observing the tide for 15 days in Muan Bay, which showed 40 minutes shorter ebbing time than at Mokpo Harbor. In addition, tidal flow prediction data in Mokpo North Harbor and Mokpo-Gu were analyzed. Meanwhile, the basis regarding qualitative interpretation of bed sediment and suspended sediment was provided by examining the qualitative changes in tidal asymmetry for spring-neap tidal cycle through the PCA/SWA indices. In addition, by examining long-term changes of ebb dominance in Mokpo Port, tidal characteristics of the past, present and future in this area, which is related to tidal asymmetry, is also provided.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.29 no.1
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• pp.279-283
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• 2005

Fisheries Surveillance System (FSS) is to protect fishing farms a thief. To implement the FSS a speacial test system which can be operate at any natural environments in the practical farm fields is needed. This paper describes some up coming results for the implementation of Radar Car as the special test system which consists of small van-type car, commercial Radar system, Radar Scan Converter(RSC) and, computer system. This Radar Car is designed to test the influences of sea clutter according to the height of Radar Scanner and to verify some effects of side-lobe suppression by special materials attached at each side of the Radar scanner. The post digital signal processing of digital radar signal comes from Radar Scan Converter(RSC) is also discussed, then designed and developed a new RSC in this study.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.29 no.1
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• pp.153-161
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• 2005

Recently, The government of Korea declared to develop RFID(Radio Frequency IDentification) as one of key strategic technology to perform U-Government using Ubiquitous technology. But, most of the related technologies for RFID are mainly focused on the inlaned application excepting marine applications. The last target of this study is to implement new Marine RFID(M-RFID) that can cover all of EEZ areas as large five times as inland volume. In this paper, as a basic study for the M-RFID, we carried out an establishing the concept design of M-RFID, developing the construction method of M-RFID and, extending the idea of M-RFID. As studying results, it is known that the M-RFID can be use in many practical areas such as the protection of EEZ area and aqua culture, the safety of fisher man, the disaster control for inlander and, fisheries ligistics with real-time.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.1
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• pp.135-140
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• 2022

Most machines are made of several types of . In particular, the shaft system of the ship consists of the brass of the propeller blade and the stainless steel of the shaft. When dissimilar the electrolyte solution of seawater, a voltaic cell and a shaft electromotive force is generated. This electromotive force causes electrical corrosion of the bearing and shaft supporting the shaft system. prevent this corrosion, a shaft grounding system is installed in ships. As for the experimental method, various information acquired by designing a program to periodically measure the electromotive force of the controllable pitchpropeller) system using an A/D converter of NI. This study analyzed the generation and characteristics of accumulator electromotive force for CPP and considered the installation location of the grounding system to remove the accumulator electromotive force.

• Composites Research
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• v.35 no.5
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• pp.347-358
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• 2022

Carbon fiber is an excellent structural material, which has been proven in many industries, and the shipbuilding industry is no exception. In particular, in advanced maritime countries, special ships of the Navy and Coast Guard with carbon fiber composite hulls have already been deployed. In Korea, carbon fiber composite materials have been applied to a 10-ton class leisure craft or a 30-ton class patrol, but no research has been done on a hundred of tons or more vessels. In this study, the feasibility study of a 500-ton patrol vessel with a carbon fiber composite hull was conducted through an analysis of similar cases abroad. As a result, it was recognized that the developed hull can be reduced in weight by about 21% to 25% compared to the existing aluminum or FRP hull. It was also confirmed that this light-weight effect can induce the improvement of the maximum speed and the improvement of the operating range via simulations.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.11a
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• pp.341-342
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• 2018

Unlike previous studies on the optimum route of the ship operating on th ocean, this study proposed an optimization method for the route planning of the ship operating on the coast. In general, passenger ships on the coast navigate along the waypoints indicated in the authorized route. Therefore this study propose objective function considering the braking power and time to determine the speed between waypoints, and the optimum speed was determined by applying the proposed method to the actual route of the passenger ship between Mokpo and Jeju.

• Journal of Environmental Science International
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• v.17 no.12
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• pp.1391-1402
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• 2008

Designating conservation sites is needed for the preservation and management of tidal flats, and also objective criteria, by which preservation values of tidal flats can be evaluated, are required to designate conservation sites. A set of new evaluation criteria or tidal flats was suggested in this study. The criteria, based on six items including scarcity, diversity, naturalness, uniqueness, destruction possibility and preservation will, ave the advantages with which easy and economic assessments are possible by using basic data from the preceding studies. The evaluation results for the three different tidal lats (Muan, Jeungdo-1 and Jeungdo-2) in the southwestern coast of Korea reveal that all he tidal flats evaluated are classified into grade 2. The tidal flat which got the highest valuation score was Jeungdo-1 tidal flat (86.7), and the next was Muan (85.0) and Jeungdo-2 (82.5). The Jeungdo-2 tidal flat was superior in uniqueness and destruction possibility, and the Muan tidal flat was superior in diversity and naturalness.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.5
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• pp.466-473
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• 2020

A marine air drone is a new device that can be used to respond to and prevent marine casualties. Determining the districts where marine air drones can be deployed helps the government decision makers identify efficient policy. The aim of this study is to develop a model using the fuzzy-analytic hierarchy process (F-AHP) and additive ratio assessment (ARAS) method to evaluate appropriate districts for deploying marine air drones. To verify the applicability of the proposed model, a case study was performed with respect to the Korea coast guard (KCG) districts. Since the deployed marine air drones are characterized by a high degree of overlap between the evaluation attributes. the F-AHP is used to determine the weights of identified criteria. The results of this study, show that missing people from the shore was the most important criterion for deployment of the drone. For ranking the local districts of the KCG, the ARAS is applied in the case study with the single goal of 50% reduction in marine casualties. Consequently, the highest priority district was identified as Mokpo, followed by Incheon, Seogwipo, Taean, Wando, Yeosu, Pohang, Tongyeong, Gunsan, Bolyeong, Jeju, Buan, Donghae, Sokcho, Ulsan, Uljin, Busan, Changwon, and Pyeongtaeg.