• Journal of Fisheries and Marine Sciences Education
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• v.12 no.1
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• pp.22-82
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• 2000

The ship hull construction materials of fishing boat has changed in order that wooden, steel, and fiber glass reinforced plastic(FRP). The fishing boat made from FRP has increased every year because that materials has proved excellent of the characteries for fishing boats construction members. Recently, FRP tend towards evasion for the pollution of air enviroment. Therefore. the materials of fishing boat construction must be exchanged by another one. Aluminium alloys must be recommended for fishing boats construction mateials because that is light weight and corrosion resisting in the sea water. Regulation of the standard of ship hull construction for aluminium alloys fishing boats did not enact laws in the interior now. Therefore, this regulation was studied by the following items. that is Rudder, Bottom construction, Side hull plate construction, Deck plate construction, piller. Water tight bulkhead, Deep tank, Fish tank, Stern construction, Superstructure, Deck house construction, Hatch, Engine room opening, Hatch opening, Bulwark, Welding and Rivet etc. A study on the regulation will be contributed to enact laws for fishing boat construction of aluminium alloys.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.2
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• pp.282-287
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• 2009

As current international guideline and IMO regulation give severe restrictions for ships to manage ballast water to reduce unintentional organism transfers, several ballast water treatment systems recently have been being developed together with filtration. That is because discharging ballast water from ships causes many pollutions by foreign biological invasive species. The primary treatment system being considered in this study was based on fine screen filtration technology applied to ballast water filter in ballast tank in order to reduce the load of ballast water treatment system. New ballast water filtration system was invented and analysed. The structural stress and strain analysis for ballast filtration systems which are current and invented filters were carried out using UGS and Ansys. The results showed that the structure of current filtering module was not designed to meet the requirement of sea water filtration during ballasting operation. The studies also showed that the invented design of filtration system equipped with back washing and automatic scrapper for eliminating cake of bio-species might be a potentially effective technology for ballast water management of ship's ballast tank.

• Journal of Korean Society on Water Environment
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• v.33 no.2
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• pp.187-196
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• 2017

To ensure hygienic safety of drinking water in a water storage tank, the concentrations of residual chlorine should be above a certain regulation level. In this study, we conducted model simulations to investigate the effects of temperature on residual chlorine in water storage tank conditions typically used in Seoul. For this, values of model parameters (decomposition rate constant, sorption coefficient, and evaporation mass transfer coefficient) were experimentally determined from laboratory experiments. The model simulations under continuous flow conditions showed that the residual chlorine concentrations were satisfied the water quality standard level (0.1 mg/L) at all the temperature conditions ($5^{\circ}C$, $10^{\circ}C$, $15^{\circ}C$, $20^{\circ}C$ and $25^{\circ}C$). Meanwhile, when the tanks had a no flow condition (i.e., no tap-water influent due to a sudden shut-down), the concentrations became lower than the regulatory level after certain periods. The findings from this modeling works simulating Seoul's water storage tanks suggested disappearance rate of residual chlorine could be reduced through the tanks design optimization with maintenance of low water temperature, minimization of air flow and volume, suppression of dispersion and the use of wall materials with low sorption ability.

• Journal of Industrial Technology
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• v.27 no.A
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• pp.15-18
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• 2007

This study investigated disinfection effect by general water purifier and water purifier with UV light disinfection. The results are as follows : (i) The general bacteria existed plentifully in a storage tank before treatment (ii) Water treated in water purifier did not meet the water treatment regulation standard since the presence of bacteria, whereas with UV light application the regulation standard is totally satisfied. (iii) Photocatalytic disinfection process with UV light in the presence of $TiO_2$ more effectively killed general bacteria than UV light only.

• Corrosion Science and Technology
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• v.7 no.4
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• pp.219-223
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• 2008

In 2006, as a means to minimize early corrosion failure of ships, thus to enhance marine safety, International Maritime Organization (IMO), proposed a mandatory regulation for Performance Standards for the Protective Coatings (PSPC) for ballast tanks of newly built ships to satisfy 15 years of target useful life. In this regulation, several unprecedented strict rules are adopted as minimum, mandatory requirements for protective coatings of ship's water ballast tanks, and all type of ships sailing international sea are subjected to this regulation which is to be effective as early as June of 2008. The PSPC addresses many technical issues in the areas of surface pretreatment (primary and secondary), coating materials, coating application procedure and inspection as well as necessary documentation. The PSPC rules are new and unproven concepts, which calls for rigorous incorporation of reality-based evidences currently available, since there are no practical experiences in terms of the validity of the PSPC rules. There has been much controversy surrounding these regulations and considerable effort has been made by both shipyards and ship owners alike to achieve a performance standard for ballast tank coatings, which is acceptable to all. In this paper, the background and overview of the PSPC rules are given, and several issues in the PSPC are reviewed as a base to achieve robustness of the proposed PSPC, which will serve as a means to minimize early corrosion and to ensure 15 year target useful life of ships.

• International Journal of Naval Architecture and Ocean Engineering
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• v.11 no.1
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• pp.274-284
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• 2019

The control architectures of Chuan Suo (CS) deep submergence rescue vehicle are introduced. The hardware and software architectures are also discussed. The hardware part adopts a distributed control system composed of surface and underwater nodes. A computer is used as a surface control machine. Underwater equipment is based on a multi-board-embedded industrial computer with PC104 BUS, which contains IO, A/D, D/A, eight-channel serial, and power boards. The hardware and software parts complete data transmission through optical fibers. The software part involves an IPC of embedded Vxworks real-time operating system, upon which the operation of I/O, A/D, and D/A boards and serial ports is based on; this setup improves the real-time manipulation. The information flow is controlled by the software part, and the thrust distribution is introduced. A submergence vehicle heeling control method based on ballast water tank regulation is introduced to meet the special heeling requirements of the submergence rescue vehicle during docking. Finally, the feasibility and reliability of the entire system are verified by a pool test.

• Journal of Korean Society of Water and Wastewater
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• v.12 no.2
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• pp.90-98
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• 1998

The optimal rechlorination in water distribution systems was investigated by incorporating optimization techniques into a numerical water quality model. For a hypothetical system that consists of 10 junctions including a storage tank and 12 links, the bulk ($k_b$) and pipe-wall ($k_w$) decay-rate constants of chlorine residual are assumed to be 2.0 1/day and 1.5 m/day, respectively. It was also assumed that the lower and upper limits of chlorine residual in the network are 0.2 mg/L and 0.6 mg/L. When the chlorine source is only the storage tank (without rechlorination), the high levels of chlorine residual appear near the storage tank to maintain the chlorine residuals above the lower limit over the junctions. On the other hand, the chlorine residuals in the network are distribute within the desirable range (0.2 - 0.6 mg/L) after the optimal rechlorination through five injection sites including the storage tank. In case of a real water distribution system that comprises 28 junctions including a clear well and 27 links, the bulk and pipe-wall decay-rate constants are 0.3 1/day and 0.2 m/day, respectively. Before rechlorination, the required chlorine residual at the clearwell is 5.1 mg/L to keep the chlorine residuals above the minimum level (0.6 mg/L) over the junctions. By the optimal rechlorination at five injection sites, the chlorine residuals are distributed within a desirable range of 0.6 mg/L through 2.0 mg/L, which can avoid the excess of chlorine residuals near the clear well. Consequently, total chlirine doses are decreased by 81% in the hypothetical distribution network and 69 % in the real distribution network for satisfying the minimum chlorine residuals.

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.2
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• pp.122-131
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• 2015

The purpose of this study is to understand the necessity for waterproofing and corrosion-resistant technique application on concrete water tank used in water supply. Relevant research materials and regulation were collected, reviewing for the case studies of sample structures aged over 20 years, and experimental studies on chloride conduction for the high performance concrete and penetration properties of water repellency of liquid type materials. The result is that the concrete water tank in the water supply is needed for waterproofing and corrosion-resistant material coating to maintain long term durability due to the constant environmentally induced degradation deterioration often caused by chloride attack.

• Journal of Soil and Groundwater Environment
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• v.14 no.1
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• pp.61-67
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• 2009

A non-discharged system of sequentially physico-chemical water treatment was used to treat the contaminated water produced from washing system of soils according to full-scale soil washing. After washing the TPH contaminated soils, the remaining concentrations of COD$_{Mn}$, SS, and n-hexane were analyzed for each compartment to estimate the treatment efficiencies of non-discharged system. Three times of sampling events were conducted for 4 different compartments (sediment tank, flocculation tank, oil/water separator, and process-water tank). In addition, soil washing efficiencies and concentrations of each parameter (COD$_{Mn}$, SS, and n-hexane) for process-water tank were analyzed for about 8 months. As results, the average efficiency of soil washing was high to have 95.9%, regardless of the condition of TPH contamination level for soils, as well as the concentrations of COD$_{Mn}$, SS, and n-hexane in the process-water tank were below the regulation limits of the Water Environmental Conserveation Act. Accordingly, the full-scale washing treatment system in this study could make the washing water 100% recycled which lead the system to be environmentally-friendly and economical.

• Journal of Wetlands Research
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• v.24 no.3
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• pp.161-169
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• 2022

In this study to estimate suitable size of rain tank in Suwon district, monthly rainfall, daily rainfall duration curve and daily rainy days have been analyzed. Annual rainwater consumption and daily average amount of storage with respect to size of rain tank have been calculated by applying continuity equations that take account of daily rainfall, daily consumptive use, storage of rain tank, It has been shown that above 50 mm of rainfall in the ordinance related to reclamation water may be inappropriate regulation if annual amount of rainfall captured, efficiency of utilized rainwater, number of days for utilized rain tank, daily average amount of storage and daily consumptive use have been considered. Thus, it has been shown that suitable size of rain tank should be determined considering reasonable daily consumptive use with respect to district, constructed cost of rain tank and benefit of rain tank constructed.