• Journal of Korean Society of Environmental Engineers
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• v.28 no.11
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• pp.1162-1167
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• 2006

The discharge of ballast water from the marine vessel without proper treatment causes the ecological disruption. Therefore, International Marine Organization(IMO) has the plan to force the proper treatment of ballast water before its discharge to open sea. To satisfy the IMO's criteria, several processes such as filtration, UV irradiation, and ozonation etc., were introduced. Since the disinfection of ballast water should be conducted within very short hydrolic retention time, electrochemical treatment can be a promissing process. The DSA(dimensional stable anode) electrode for the electrochemical treatment was prepared by thermal deposition method. The disinfection rate of microorganisms increased with the increasing current density and reaction time under low pH condition. The morphology of sterilized microorganisms was shown by SEM and Microscopy.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.04a
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• pp.227-232
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• 2004

Ballast water from ship harmful microorganism sterilized use of electrolytic sterilization system. The experimental methods were use of peristaltic flow pump upward on electrode pole. Due to reaction time, HRT were unlike microorganism on flow rate. In electrolysis, dioxide iridium coated titanium(Ti／IrO$_2$) and stainless steel plate were used for anode and cathode respectively. Current density controls make use of D.C Power supply on 250V 100Amper. Experimental use of current density between 0.1 and 0.5A was able to disinfect microorganism at 5 seconds by the reaction time. This study shows that the electrolyzed water has a potential for the sterilization of ballast water.

• Journal of Navigation and Port Research
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• v.29 no.10 s.106
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• pp.865-870
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• 2005

Because there are only a limited number of means of action that are available for the master to pursue in the event of flooding, onboard decision support system has been required. The majority of systems activated during a flooding emergency (such as watertight and semi-watertight doors, bulkhead valves, dewatering pumps etc.) almost exclusively aim to restore a sufficiently high level of subdivision to prevent flooding from spreading through the ship. Even though assuming the flooding scenario is not catastrophic, the use of ballast tanks can be an additional and very effective tool to ensure both prevention of flooding spreading and also improve ship stability. This paper describes an optimization algorithm devised to choose the set of ballast tanks that should be filled in order to achieve an optimal response to a flooding accident.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2005.10a
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• pp.75-80
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• 2005

Because there are only a limited number of means of action that are available for the master to pursue in the event of flooding, onboard decision support system has been required The majority of systems activated during a flooding emergency (such as watertight and semi-watertight doors, bulkhead valves, dewatering pumps etc.) almost exclusively aim to restore a sufficiently high level of subdivision to prevent flooding from spreading through the ship. Even though assuming the flooding scenario is not catastrophic, the use of ballast tanks can be an additional and very effective tool to ensure both prevention of flooding spreading and also improve ship stability. This paper describes an optimization algorithm devised to choose the set of ballast tanks that should be filled in order to achieve an optimal response to a flooding accident.

• Transactions of the KSME C: Technology and Education
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• v.4 no.2
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• pp.85-92
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• 2016

During ballast of a LNG carrier, the mud at the sea floor can enter the tanks together with the ballast water if the LNG terminal is located at shallow water region. In order to remove the mud deposited on the tank floor during deballasting, the mud flushing system in the ballast tanks is applied. In this study, various analyses to conform the efficiency in the mud removal are performed. In order to design the mud flushing system, the particle size of the mud is measured by particle size analyzer. Flushing performance is evaluated by numerical analysis. From the results of numerical analysis including flow field and piping system network, the optimized flushing system is determined.

• Journal of Navigation and Port Research
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• v.28 no.10 s.96
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• pp.955-960
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• 2004

The treated ballast water from previous treatment contains microorganisms and pathogenic organisms in an electrolytic treatment system. The experimental methods included using a peristaltic flow pump placed upward on an electrode pole. Due to the reaction time, the hydraulic retention time indicated unlike microorganisms on the flow rate. In electrolysis, dioxide iridium-coated titanium (Ti/Ir02) and stainless steel plates were used for the anode and cathode, respectively. Current density controls make use of a DC power supply on 250V, 100Amper. Experimental use of a current density between 0.1 and 1.0A/dm2 was able to disinfect the microorganism (E. coli, Bacteria, Bacillus sp.) in seawater for 5 seconds of reaction time. The removal rate was approximately $90\%,$ while the current density was 2.0A/dm2 and the electrode distance was 75mm. This study shows that the electrolytic treatment system has a potential for the sterilization of ballast water.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.1320-1321
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• 2008

펄스파워기술은 저장된 전자에너지를 시공간적으로 압축 중첩하여 극히 짧은 시간안에 대전력을 발생시켜 좁은 공간에 에너지를 집중 공급하는 기술이다. 여기에는 에너지를 저장하는 충전장치에 대한 기술과, 빠른 시간에 에너지를 방출하는 스위칭기술, 파형을 성형하는 펄스포밍 네트워크 기술등을 포함하며, 이를 이용한 응용기술로 플라즈마건, 이온빔 가속장치, 펄스성형용접, 수처리 발라스트, 파암장비, 코일건, 레일건 등이 있으며, 이 응용분야에 오래전부터 이용되어 왔다. 이러한 분야에 적용되는 펄스전원장치는 이동성이 용이해야 하고, 부피 또한 작은 구조를 가져야 한다. 본 논문은 고집적화 펄스전원장치의 츠로토 타입 설계, 제작, 실험에 관한 논문으로 그 중 펄스성형을 이뤄내는 인덕터에 대한 성능 실험 결과를 위주로 한다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.4C
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• pp.185-191
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• 2010

Volumetric pressure plate extractor (VPPE) can be used for measurement of the soil-water characteristic curve in the laboratory using the axis-translation technique. The volume of extracted water from the soil specimen in VPPE can be measured continuously during the test without stoppage of air pressure for the measurements. However, the water volume measurement in VPPE using an air trap, a ballast tube, a burette, and a vacuum device so as to maintain a constant pore-water pressure in the soil specimen, is quite complicated and tedious. In order to improve the measuring problems of VPPE, a modified volumetric pressure plate extractor (MVPPE) was developed and tested on residual soil specimens. In addition, the modified apparatus can measure the volume of the extracted water using both Method A and Method B of ASTM D 6836-02 depending on the range of matric suction. Measuring principles and the improvements of MVPPE and typical results obtained from the tests are discussed in the paper.

• Journal of Navigation and Port Research
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• v.32 no.1
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• pp.1-7
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• 2008

Since the shipbuilding industry is at its peak to assimilate the large volume of orders in recent years, the Floating Dock has been an alternative to the dry dock which takes a certain period of time to build. Hence the use of Floating Dock is steadily increasing. Since the Skid Launching System(SLS) is used in Floating Dock, the balancing of the ship while launching is important and achieved by adjusting the Ballast tank of the Floating Dock. In this paper a Floating Dock Control Simulator for SLS is developed through the on-line interface of VRC(Valve Remote Control), Tank Level & Draft Measuring System and Valve Control algorithm on Simulation Tank Plan.

• Journal of Navigation and Port Research
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• v.33 no.6
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• pp.375-380
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• 2009

The authors had consisted the construction of shipyard must be investigated under the consideration of long term ship's demand and so the Floating Dock might be an alternative to the dry dock. This paper shows a development of Floating Dock Controller for Skid Launching System(SLS). While loading out a block to the Floating Dock and launching ship from the Floating Dock, the balancing of the ship and the dock is very important and achieved by adjusting the Ballast tank of the Floating Dock In this paper a Floating Dock Controller for SLS was developed through the on-line interface of VRC(Valve Remote Control), Tank Level & Draft Measuring System and Valve Control algorithm on Tank Plan. The control system developed was applied to a shipbuilding and verified good and stable.