• Proceedings of the KIEE Conference
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• 2009.04a
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• pp.192-194
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• 2009

This study presents on the analysis fire hazards of communication cable. In order to analyze fire hazards fire retardant tests and con-calorimeter test is conducted. The fire retardant tests are IEC 60332-1 and UL 94 test. The results show that IEC 60332-1 test and It 9t test are not effective to estimate fire hazard. And various parameter is obtained by con-calorimeter test. It is necessary to analysis effectively fire hazards of cable for new fire retardant test.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.11a
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• pp.208-208
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• 2004

• Proceedings of the KIEE Conference
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• 1987.11a
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• pp.143-146
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• 1987

Fiber optics provide a solution to the problems at interference, capacity and reliability in communication. Approximately 20 kilometera of a six-fiber, multimode, longwave($1.3{\mu}m$), graded index silica glass fiber optic cable was helically wrapped around a phase conductor at a Korea Electric Power Corporation(KEPCO) 154KV transmission line. This paper presents an economic comparison of several fiber optic cable installation alternative and discusses the characteristics at the helically wrapped fiber cable, as well as the entire installation, including high voltage phase-to-ground (PTG) end termination, and splicing. The fiber link was installed for the field trial and practical use with overhead composite optical fiber cable which installation performed a few years earlier some other location and is intended to accommodate not only telephone but also supervisory Control and Data Acquisition(SCADA), protective relaying, and telemetry functions.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.4 no.2
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• pp.24-33
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• 1993

In indoor radio systems, vehicular communication systems, and land mobile systems, a very important problem is that of maintaing stable communications at all locations. Therefore solutions for the indoor propagation problem are an important aspects of the mobile communication system. Leaky coaxial cables finding increasing use in communications systems involving mines, tunnels, railroads, and highways, and in new obstacle detection, or guided radar, schemes for ground transpor- tation and perimeter surveilance. In this paper a leaky coaxial cable having periodic slots in the outer conductor is described to obtain the propagation modes in the various environments. We use an essentric cylindrical model to develop the theory for surface-wave propagation on the cable. Numerical Results are also included for the propagation constants, field distribution and impedance as functions of various parameters. First, we derive the electromagnetic equation for leaky coaxial cable having periodic slots using mode-matching method and Floguet's theorem, and then find various modes, propagation constants, field distribution, etc.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.2
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• pp.69-74
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• 2015

Recently, there has been a surge in interest in equipment diagnosis and monitoring technology from the perspective of providing quality electricity in terms of reliability and safety. In order to meet the electrical demands of consumers, reliability of power supply needs to be maintained. For this purpose, a monitoring system for power cable is very important. Since real-time measuring equipment has many advantages, it is highly applicable. By measuring the load current and the surface temperature of power cables, we have monitored and identified the deterioration phenomena of power cables in operation. Since direct measurement of the cable conductor temperature is not easy, we have measured the surface temperature instead, and converted that temperature to obtain the conductor temperature of the cables. In addition, we have designed a system to detect the deterioration processes of the power cables in operation.

• Journal of the Korean Professional Engineers Association
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• v.44 no.5
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• pp.42-47
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• 2011

Currently, wireless communication environment in high-rise buildings are limited in the basement and ground floor facilities are not in common use do not part, in case of disaster is difficult for efficient repression. In this paper, wireless communication facilities on the ground floor of the skyscraper by building infrastructure, wireless communications is proposed to eliminate shadows. That the presence of various wireless communication systems, wireless communication system proposed by this paper, TPS laying coaxial cable seals leak, and the propagation shades in place by installing indoor antenna is the solution to eliminate shadows. The wireless communications solutions reveal the advantages and features, a method of constructing the proposed design.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37A no.12
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• pp.1115-1121
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• 2012

In this paper, the design of UTP LAN cable with enhanced alien crosstalk characteristic is proposed. Proposed LAN cable is made with jacket of the irregularly corrugation type. If necessary, it is possible to use the special cross-filler. The alien crosstalk characteristic is enhanced by using proposed cable with inner jacket of the irregularly corrugation type in wide frequency band. The design of the cable was based on parameters of the standard EIA/TIA 568-B.2-10.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.3
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• pp.1030-1050
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• 2021

The edges with "bridge characteristic" play the role of connecting the communication between regions in power optical cable network. To solve the problem of mining edges with "bridge characteristic" in provincial power optical cable network, the complex power optical cable network model is constructed. Firstly, to measure the generated potential energy of all nodes in n-level neighborhood local structure for one edge, the n-level neighborhood local structure topological potential is designed. And the minimum connected chain attenuation is designed to measure the attenuation degree caused by substituted edges. On the basis of that, the minimum connected chain attenuation topological potential based measurement is designed. By using the designed measurement, a bridge-edges mining algorithm is proposed to mine edges with "bridge characteristic". The experiments are conducted on the physical topology of the power optical cable network in Jilin Province. Compared with that of other three typical methods, the network efficiency and connectivity of the proposed method are decreased by 3.58% and 28.79% on average respectively. And the proposed method can not only mine optical cable connection with typical "bridge characteristic" but also can mine optical cables without obvious characteristics of city or voltage, but it have "bridge characteristic" in the topology structure.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.4
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• pp.205-209
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• 2015

The economic losses resulted from the accident in the power cables at the power station is not only huge but also requires a great amount of time and expenses to restore to the former condition. In order to prevent these, it is necessary to invent and apply a technique to expect and prevent the accidents. In order to measure insulation resistances of power cables in operation, we derived the relations between load current and temperature. By analyzing data obtained from our measuring equipments, we showed the expected time to change deteriorated cables before accident occurs. We present a result of our study on the effects of the load current on lifetime of 6.6 kV cable systems in operation. With the current flowing through the load of the cable a heat is generated reducing the lifetime of the cable. In order to find out the effect of load current on the lifetime of cable systems, we applied the lifetime theory to the development of two equipments to measure insulation resistance and current of cable systems in operation.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.4
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• pp.205-211
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• 2014

With a development of modern industry, demand for electric power is rapidly increasing and the capacity of power transfer is required to become bigger and bigger. At power station, the high-voltage power cable is used as the only method in order to transfer electric power. In this paper, we have analyzed the deterioration characteristics of 6.6kV power cable systems in operation. For the time duration of 2000 days, we have measured the cable in operation in order to extract the data for the deterioration characteristics. By analyzing the data by means of several steps of filtering processes, we could obtain the linear relations of insulation resistances as a function of time. Furthermore, we can verify that the progress characteristics in deterioration process of 6.6kV power cable systems follows the process of heat deterioration.