• Journal of Navigation and Port Research
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• v.43 no.5
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• pp.302-309
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• 2019

This study introduces the navigational environment database(DB) compiling water depth, sediment type and marine managed areas (MMAs) in coastal waters of South Korea. The water depth and sediment data were constructed by combining their sparse points of electronic navigation chart and survey data with high spatial resolution using the inverse distance weighting and natural neighbor interpolation method included in ArcGIS. The MMAs were integrated based on all shapefiles provided by several government agencies using ArcGIS because the areas should be used in an emergency case of ship. To test the validity of the constructed DB, we conducted a test application for grounding and anchoring zones using a ship accident case. The result revealed each area of possible grounding candidates and anchorages is calculated and displayed properly, excluding obstacle places.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.1474-1479
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• 2004

In electrification of the Honam line, the grounding method of the copper wire shield of 66kV feeder cable was disputed. This paper describes that the review of the proper earthing method(one-side earthing or both-side earthing) under consideration of the site condition and the acceptability of the induction voltage of the shield on the end of the cable.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.57-60
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• 2001

CATV is the abbreviation for Cable Television. General CATV is a way of multi-channel sending images, voices and music including stillness image as well as characters to public receivers through electrical cable communication system. In the beginning, master antennas were people can not receive TV signal well. TV programs were received from master antennas to TVs in each house. Ground connection began by experimenting lightning with the use of a kite and it means electric appliances, communication equipments, measuring instruments and so on connecting the Earth in order to flow away overcharged electricity. There are two kinds of earth connection: Power Ground and Signal Ground. Power Ground is for preventing an electric shock and in general there's no current in the connector. However in an accident, there's a quick flow of electricity out to the Earth. Signal Ground is not only for the safety of appliances but also for the safety of equipment operation. This paper is about connection for noise and interference reduce in order to prevent wrong operation and distortion of signal in the electrical appliances which can take place in CATV.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.37 no.3
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• pp.58-63
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• 2000

For the microwave high density devices and modules of the 3D configuration, we proposed radial stub for the ground connection. The proposed structure is analyzed by the full-wave analysis of finite element method (FEM) and characterized experimentally. The results show that the return loss is more than 15 dB and the insertion loss is less than 0.5 dB in the frequency range from 2.5 GHz to 6.3 GHz. The proposed grounding scheme will be useful for the ground connection lot the microwave high density devices and module of 3D configuration.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.57-60
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• 2001

CATV is the abbreviation for Cable Television. General CATV is a way of multi-channel sending images, voices and music including stillness image as well as characters to public receivers through electrical cable communication system. In the beginning, master antennas were people can not receive TV signal well. TV programs were received from master antennas to TVs in each house. Ground connection began by experimenting lightning with the use of a kite and it means electric appliances, communication equipments, measuring instruments and so on connecting the Earth in order to flow away overcharged electricity. There are two kinds of earth connection: Power Ground and Signal Ground. Power Ground is for preventing an electric shock and in general there's no current in the connector. However in an accident, there's a quick flow of electricity out to the Earth. Signal Ground is not only for the safety of appliances but also for the safety of equipment operation. This paper is about connection for noise and interference reduce in order to prevent wrong operation and distortion of signal in the electrical appliances which can take place in CATV.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2002.11a
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• pp.343-347
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• 2002

This paper analyzed the effect of breakdown electric current and it establishes a countermeasure that objective of the place where it put when with protection method which is applied from the existing electric railroad power supply system and where the protection method which is applied in the newly electrified system. Will reach and in order to attain simulation it did a actual power supply system and it analyzed that result.

• Proceedings of the KIEE Conference
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• 2000.11b
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• pp.355-357
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• 2000

Measurement used electricsal sounding(MacOHM 2115, Japan) for grounding resistance of Jung-Bu highway Ha-Nam IC about 500m. To applied measurement method is fall of potential method and analysis earth resistivity used ESII(Electrical Sounding Interactive Interpretation) program. This result propose for construction plan of electric corrosion.

• Proceedings of the KIEE Conference
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• 2000.11b
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• pp.358-360
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• 2000

Measurement and analysis for earth resistivity and grounding resistance of Jeon-Ju's widearea-waterworks water pipe line. This result propose to improvement method for exactness analyze the causes for lack of corrosion voltage.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.7
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• pp.905-912
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• 2013

Power system fault analysis is commonly based on well-known symmetrical component method, which describes power system elements by positive, negative and zero sequence impedance. In case of balanced fault, such as three phase short circuit, transmission line can be represented by positive sequence impedance only. The majority of fault in transmission lines, however, is unbalanced fault, such as line-to-ground faults, so that both positive and zero sequence impedance is required for fault analysis. When unbalanced fault occurs, zero sequence current flows through earth and skywires in overhead transmission systems and through cable sheaths and earth in cable transmission systems. Since zero sequence current distribution between cable sheath and earth is dependent on both sheath bondings and grounding configurations, care must be taken to calculate zero sequence impedance of underground cable transmission lines. In this paper, conventional and EMTP-based sequence impedance calculation methods were described and applied to 345kV cable transmission systems (4 circuit, OF 2000mm2). Calculation results showed that detailed circuit analysis is desirable to avoid possible errors of sequence impedance calculation resulted from various configuration of cable sheath bonding and grounding in underground cable transmission systems.

• 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.