• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.148-150
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• 2003

A meaning of power quality has changed, which affects on an environmental change of existing electricity supply markets. Today, it should take both consumers and suppliers into consideration to develop information and communication technology and to increase the use of power and electronic equipments. As a result, it is necessary to develop a system to monitor power quality and to display data. In this paper, a system, as a power quality monitoring equipment, which can use protective replays with progress of microprocessor technology and provide information in the intranet/internet circumstances using web-based architecture is described.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.151-153
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• 2003

This paper was studied on using data of the protective relay by Power Quality Monitor. The protective relay will have problem to save data for PQM(Power Qualify Monitoring) analysis because the protective relay memory is limited. So this paper was proposed new data compression of the data was get from the protective relay. The scheme is compared each cycle after DFT(Discrete Fourier Transform). And scheme is verified through simulation of protective relay data was from real distribution system.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.2
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• pp.261-267
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• 1995

Low-salted and fermented squid product, squid jeotkal was prepared with the addition of 10% salt and fermented for 50 day at 1$0^{\circ}C$. During fementation of squid, sensory evaluation and changes of volatile components were examined. Volatile flavor components in raw squid and low-salted squid jeotkal were extracted using a rotary evaporating system. The volatile concentrates were identified by GC and GC-MS. Major volatile components of raw squid were methional and 2-methyl-2-propanol. However, alcohols such as propanol, isoamyl alcohol, methionol and phenylethyl alcohol increased during the period of fermentation. The model reaction using microorganism was carried out, in order to confirm formation mechanism ofvolatile flavor compounds of the squid during fermentation. The main volatile components of Pseudomonas sp. D2 model system were isoamyl alcohol and acetoin. Those of Staphylococcus xylosus model system were isoamyl alcohol and phenylacetaldehyde.

• Microbiology and Biotechnology Letters
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• v.27 no.6
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• pp.446-451
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• 1999

The protease produced by Mucor racemosus f. racemosus PDA 103 from meju was purified by precipitating with 80% saturated ammonium sulfate, CM Sephadex C-50 ion-exchange chromatography, and secondary Sephadex G-100 gel filtration chromatography. The specific activity of the purified enzyme was 60.1unit/mg protein and the purification fold of the enzyme was 83.5. The molecular weight of the enzyme was estimated 33,746Da and the enzyme was elucidated as monomer by LC-MS and SDS-PAGE. The number of amino acids was evaluated about 330 residues.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.8
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• pp.1107-1114
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• 2012

In this paper, we propose protective coordination and automatic setting method using agents for distribution system with loop. The proposed protection scheme adopts an agent technology assuming communication among protection agents and auto-switch agents. Having exchanged fault-related information with each other, protection agents and auto-switch agents perform the primary and backup protection and fault section isolation, respectively. this proposed scheme using agents for distribution system with loop is implemented by matlab. Because of the various configuration of distribution system, It's difficult to find cooperative agents for each agent. This paper develops a program to automatically set the cooperative route for the agents.

• Proceedings of the KIEE Conference
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• 2003.11a
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• pp.202-204
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• 2003

This paper suggests an optimal parameter setting method by use of parametric protectability index, as the objective function. In this paper, a gradient based optimization method is used under the assumption that the initial values of a parameter is in a convex set including the optimal value, which is verified by a plenty of simulation studies. The proposed method is applied to a sample distribution network to shows its effectiveness.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.10
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• pp.1321-1327
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• 2014

Faulted section identification is one of the most important function in distribution automation systems. Conventional over current detection based fault indicators frequently mal-operate due to the reverse fault current from the renewable energy resources. This paper present a new faulted section identification method based on the fuzzy decision making technique. In order to establish feasibility of the proposed method, case studies using Matlab Simulink has been performed.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.2
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• pp.33-39
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• 2015

Power supplying capacity of the distribution feeder should be maintained within thermal capacity of the wire. This paper presents the minimum spanning tree based load balancing technique to release multiple overloading of distribution feeders. In order to minimize number of involved backup feeders, Dijkstra and Prim algorithm are adopted to construct minimum spanning tree. Simulation testing result based on part of KEPCO's commercial distribution systems shows effectiveness of proposed scheme.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.9
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• pp.75-81
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• 2008

The effect of the fault could be propagated to healthy region when the fault on the power system is not cleared in time. In order to enhance reliability of the protective relay, a dual and/or backup system is adopted for the power system protection. The IEC61850 has become an international standard of the substation automation system for interoperability between heterogeneous IEDs from different vendors. This paper introduces a reliability enhancement technique for the substation automation system using characteristics of the IEC61850.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.3
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• pp.87-94
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• 2013

The main purpose of the distribution automation system (DAS) is to achieve efficient operation of primary distribution systems by monitoring and control of the feeder remote terminal unit(FRTU) deployed on the distribution feeders. DAS simulators are introduced to verify the functions of the application software installed in the central control unit(CCU) of the DAS. Because each DAS is developed on the basis of its own specific data model, the power system data cannot be easily transferred from the DAS to the simulator or vice versa. This paper presents a common information model(CIM)-based DAS simulator to achieve interoperability between the simulator and the DASs developed by different vendors. The CIM-based data model conversion between Smart DMS (SDMS) and Total DAS (TDAS) has been performed to establish feasibility of the proposed scheme.