• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• 제22권4호
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• pp.78-84
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• 2008

Inundation of substation and ground power equipment broke out every summer season in low-lying downtown and low-lying shore by localized heavy rain, typhoon and tidal wave. In case inundation excluding the exchanging cost of equipment, it occurs a great economic and social loss owing to recovery time and events of electric shock occur by inundation electrical facility. So we researched the installation situation of substation and power equipment and inundation loss at Flood Danger Area. And we analyzed refutation or law relating to the flood protection counterplan of US, England Australia. We present flood protection countermeasures by survey and analyzing the internal standard and his paper will be used to resent a reform proposal of electrical feinted law about flood protection.

• Proceedings of the Korea Water Resources Association Conference
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• 한국수자원학회 2017년도 학술발표회
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• pp.329-329
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• 2017

In this study attempted to evaluate the stability of the protection methods by examining hydraulic characteristics of the area around the point in which marine cable protector is installed such as surf zone occurrence point of shore-end submarine cables suitable for coastal marine environmental conditions, flow rate t the tope of the protector and maximum wave height, and to provide basic data for the selection of the optimal protection method. In performing hydraulic model experiments, the topography of submarine cable installation location was reproduced in 2-D sectional channel, and models appropriate for experimental scale and similitude law were produced and installed for each condition of submarine cables and protectors. Since the topography and submarine cable protectors were reproduced and installed in 2-D sectional channel, the exact reproduction of surf and transformation in shallow water zone was possible, and thus the physical properties could be clearly analyzed. For stability review, an experiment to examine the stability was conducted using a wave maker with 50-year frequency design waves as target, and wave height and cycles were applied based on the approximate lowest low water level(Approx. L.L.W), which is the most dangerous in submarine cable protection methods. As for experimental time, typhoon passing time in summer (about 3 hours) was applied, and wave patterns and deviation ratio of the submarine cable protector were investigated after making irregular waves corresponding to design waves. In addition, current meter and wave height meter were installed at the installation location of the submarine cable protector, and the flow rates and wave height at the top of the protector were measured and analyzed to review hydraulic properties.

• Proceedings of the Korean Geotechical Society Conference
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• 한국지반공학회 2000년도 가을 학술발표회 논문집
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• pp.177-184
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• 2000

Geotube is a tube made of geotextile and hydraulically filled with dredged soil. This technological method has been widely used in the advanced countries of the world to build the shore protection embankment. The dredged contaminated sediments from the lake, river, and harbor can be pumped into the geotube by using the hydraulic pump. So, environments effects can be minimized and enhanced by using this method. This paper presents a field test result of a geotube in the land reclamation project for the Songdo New City construction site. The dredged silty clay was dredged by the dredging ship and hydraulically pumped into the geotube. The height of geotube was measured at every filling stage and also measured width and diameter of geotube with the elapsed time. The unit weight of soil and undrained shear strength of filled soil in a tube were measured at the various locations and heights of geotube with the elapsed time. Geotube technique can be effectively implemented for the silty clayey soil with using the dredging ship.

• Proceedings of the Korean Geotechical Society Conference
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• 한국지반공학회 2002년도 봄 학술발표회 논문집
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• pp.549-556
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• 2002

Geotextile tubes hydraulically or mechanically filled with dredged materials have been applied in hydraulic and coastal engineering in recent years(shore protection structure, detached breakwater, groins and jetty). It can also be used to isolate contaminated material from harbor, detention basin dredging, and to use this unit as dikes for reclamation work. Recently, new preliminary design criteria supported by model and prototype tests, and some stability analysis calculations have been studied. The stability analysis of geotextile tube is composed geotechnical and hydrodynamic analysis. The stability check points are sliding failure, overturning, bearing capacity failure against the wave attack. In this paper presented the construction procedure and in-situ measurement(properties of filling material, effective height variation, stress variation at geotextile tube bottom) of geotextile tube at Young-Jin Bay and stability analysis by theoretical method and hydraulic model tests

• Journal of Navigation and Port Research
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• 제29권3호
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• pp.227-234
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• 2005

It is said the maritime labour law that total legislation system regulate all relationship concerning a labour of seafarers. A possibility of danger, a helplessness from the shore, a importance of the responsibility, a segregation from the public, etc. is mentioned as the particularity of a maritime labour which is distinguished from that of a shore labour. Therefore, the improvement of social standing and protection of rights for seafarers may be achieved substantially by the maritime labour standards considering such particularity of maritime labour. A vessel is itself international relationship, accordingly maritime labour is also same. It means that international relationship should be considered, whenever any country makes it's national law for maritime labour. Therefore, this paper aims to find out the spirit of legislation for the maritime labour law through a historical study on the development of it, and suggest the facts that should be considered for legislation of domestic law concerned.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• 제8권2호
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• pp.9-16
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• 1990

This is a geodetic study on the the shoreline changes occurred by the facilities constructed in the beach. There are emperical, hydrological and numerical methods in predicting of the shorline changes. Numerical method is the most suitable method in the field of geodesy. There are many predicting models. This study adopted one-line model because it has a few hydrological factor and simplify the natural phenomena. This study established the ideal seawall boundary condition, applied the explicit model and the implicit model in the Dongsan harbour in East Sea, and could predict the optimum seawall position for protection of shore. The results are following ; Seawall protect shore of which input angle of wave is below 20$^\circ$, a ratio of wave height bleak/line does not effect in shoreline changes. The implicit model is accuracy but can not predict longtime change. But the explicit model is the opposite of the implicit model.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 한국항해항만학회 2006년도 Asia Navigation Conference
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• pp.105-114
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• 2006

Together with the trend of enhancement in domestic industrial development and economic progress due to import and export, the demand for construction of the roads, bridges, especially port facilities, and several coastal protection and ocean structures is increasing rapidly. MOMAF of Korean Government is driving construction of 9 new ports and renovation of the existing fishery ports. Among these structures most of bridge base, wharves, dolphins, quays, and jetties are being newly built of steel or concrete pile. As the base, supporting bulkheads, and piles are underwater after construction, it is difficult to figure out the status of structures and not enough to get maintenance and strengthen the structures. Every year, moreover, these works suck the government budget due to higher incomplete maintenance expense for protection from corrosions of structures and increased underwater construction period. for the purpose of cutting down the government budget, it is necessary to extend the life cycle of the existing structures. We developed a new method for maintenance of submerged structures near the waterline by allowing dry work environment with the floating caisson. The method shows easy to move around the working area and handle. It also showed not only a significant reduction of maintenance expenses and time for anti-corrosion work but also better protection. This will be a milestone to reduce the maintenance and construction expenses for the shore and water structures.

• Journal of Korean Society of Coastal and Ocean Engineers
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• 제20권4호
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• pp.342-354
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• 2008

Some statistical characteristics of deepwater waves along the Korean coast have been investigated using various sources of wave measurement and hindcasting data. For very large waves comparable to design waves, it is recommended to use the average value of the empirical formulas proposed by Shore Protection Manual in 1977 and by Goda in 2003 for the relation between significant wave height and period. The standard deviation of significant wave periods non-dimensionalized with respect to the mean value for a certain significant wave height varies between 0.04 and 0.21 with a typical value of 0.1 depending upon different regions and different ranges of significant wave heights. The mean and standard deviation of the principal deepwater wave direction are presented at the 106 coastal grid points along the Korean coast. For relatively large waves, the probability density function of the directional spreading parameter $s_{max}$ is expressed as a lognormal distribution. The most suitable frequency spectrum in the Korean coast is the TMA spectrum. The probability density function of the peak enhancement factor $\gamma$ is also expressed as a lognormal distribution, with its mean value of 2.94, which is close to the value in the North Sea.

• Journal of Korean Society of Coastal and Ocean Engineers
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• 제23권4호
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• pp.292-303
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• 2011

A new type of sand bypassing system is proposed for recovering the eroded beach in this study. This system provides an added methodology to the soft defence which is main recovery method for the coastal shore protection in the world. The study proposes a conceptional design and manufacturing procedure for the relatively small size machine of sand bypassing. In order to get the discharging volume information, the power capacity of the system is tested in the field. The discharge rate of the new system shows up to the expected maximum of 618 ton/hr which is 9.6% lower than that by theoretical calculation. It gives a resonable agreement in this system when the flow is assumed to be of the high density. In this study, the delivering volume of sand is estimated according to the discharge rate. The combination of 300 mm(12 inch) intake and 250 mm(10 inch) discharge pipe line has the pumping capacity of $103\;m^3/hr$ which is nearly the same as that of South Lake Worth Inlet sand bypassing system, Florida, U.S.A.. The proposed system added the mobility to its merit. The unit price of Florida's sand bypassing is $$8~9/m^3$ (US). The system would be economically suitable for small volume of sand because no additional equipment is necessary for the intake. The diesel fuel of 25~30 l/hr was consumed during the system operation. The multiple working system would be the next investigation target for large volume of sand.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• 제19권4호
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• pp.85-90
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• 2005

Inundation of Transformer Vault breaks out every summer season in low-tying downtown and low-tying shore by localized heavy rain, typhoon and tidal wave. In case inundation of Transformer Vault, it occurs a great economic loss owing to recovery time and events of electric shock occur by inundation electrical facility. So we need installation plan of Transformer Vault in common flood area for preventing from economic loss and equipment events. Therefore we research distribution of 22.9[kV] Transformer Vault in common flood of the country and analyze field condition about flood protection plan. And we analyze regulation or law relating to the flood protection counterplan of US, England, Australia. This paper will be used to present a reform proposal of electrical related law about flood protection of existing Transformer Vault. Also we present considering facts at the time Transformer Vault installation in common flood area.