• JOURNAL OF ELECTRICAL WORLD
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• no.9 s.105
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• pp.92-95
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• 1985

OA기기에서의 접지기술은 어디라든지 그랜드라는 용어를 목적에 따라 구분, 사용하거나 포함하고 있는데 기본적인 목적은 네가지의 경우로 대별된다. 즉 (1)안전면에서 본 감전방지 (2)전자회로에서의 전자방해의 억제는 임피던스를 가진 접지이며 본질적인 문제는 여기에 있다. 한편 OA기기를 설치하는 환경은 대지 접지를 할 수 없는 케이스가 증가되고 있으며 EH 다른 문제가 부상되고 있다. 이같은 시점에서 OA기기에서의 접지기술의 현상과 문제점의 일단을 설명한다.

• Progress in Superconductivity and Cryogenics
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• v.10 no.1
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• pp.37-41
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• 2008

Superconducting Electrodynamic suspension(EDS) system is generated by the interaction between the magnetic field made by the induced the eddy current in the ground conductor and the moving magnetic field made by onboard superconducting magnet. The levitation force of EDS system, which is proportional to the strength of the moving magnetic field, becomes saturated according to the increase of the velocity. Especially, the levitation force is influenced by the structure of HTS magnet and ground magnet. This paper deals with the optimal design condition for the HTS levitation magnet. The 3-D numerical analysis with FEM was used to find the distribution of the magnetic field, the optimal coil structure, and the calculation of the levitation force.

• Journal of the Korean Applied Science and Technology
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• v.29 no.4
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• pp.653-658
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• 2012

There is an increasing interest in the use of electrochemical methods for the food waste treatment. The technologies using the electrochemical method provide ideal tools for approaching industrial and food wastes problems. Unlike other chemical treatments, the electrochemical systems do not make the volume of the secondary waste increase. The electrochemical methods can be operated with electrochemical apparatus and inorganic agent allow selective separation and recovery and even quieter than others. This study concerns design factors, electrode construction and wastewater treatment process of the electrochemical apparatus. The experiment of color, COD and BOD removal is much effective in using electrochemical method with ultrasonication and ozonation.

• 한국연소학회:학술대회논문집
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• 2004.11a
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• pp.70-75
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• 2004

The effect of electric fields on the stability of non-premixed laminar lifted flame in coflow jets has been investigated by applying high voltage alternative current (AC) to the nozzle of propane fuel. The stable lifted flame which exist in far field of jets, the liftoff height was not effected by applied voltage. This implies that the cold jet between the nozzle and flame base can be analyzed with the previous cold jet theory. Flame liftoff and reattachment velocities were also measured as function of applied voltage and frequency. The fuel jet velocity at flame liftoff and reattachment increased with increasing voltage, implying that the range of flame srability can be extended with the AC charging. However the liftoff velocity increased with frequency of AC charging on nozzle, whereas the reattachment velocity decreases with frequency. The liftoff and reattachment velocities were correlated linearly with voltage considering the effects of frequency.

• 전기의세계
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• v.38 no.6
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• pp.26-36
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• 1989

고속전철은 우리나라의 철도관련기술을 한단계 끌어올릴 수 있는 획기적인 계기로 삼아야 할 것이다. 따라서 어떠한 방식의 고속전철을 채용하느냐의 문제는 장래에 세계적인 철도의 수요가 어떠한 방식을 선호하게 될 것인지 그러므로써 우리가 보유하게 될 철도기술을 얼마나 활용할 수 있을지 등이 장기적인 안목으로써 충분히 고려되어야 할 것이다.

• 전기의세계
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• v.29 no.4
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• pp.205-211
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• 1980

부하관리는 공급관리와 더불어 전력수급관리의 새로운 전략이라 할 수 있으며, 작금의 에너지 위기에 현명하게 대처하는 중요한 수단으로 부상하고 있음을 알 수 있다. 그리고 부하관리체계의 도입을 위하여는 한계비용 및 시간대별 전력요금제로의 개편, 절전기구의 개발, 대체에너지의 개발, 부하관리 대상 부하의 창출, 통신 또는 전송제어기술의 도입 또는 개발 등이 선행되어야 하기 때문에 우리나라에서도 이방면에 대한 사전준비가 필요할 것으로 믿어진다.

• Proceedings of the KIEE Conference
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• 2001.04a
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• pp.362-365
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• 2001

Maglev Project Team in KIMM has been leading Maglev development in Korea for the past 10 years. In this paper status of development of Maglev in Korea - what has been done so far, problems to be overcome for the actual implementation and future development plan is reported.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.942-944
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• 1993

This paper treats of the recent trends in the development, of the Magnetically levitated vehicle(Maglev) and the propulsion system of the Maglev in the world. Consequently, the material data for the guide post in the research and formulation of development policy are prevented.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1159_1160
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• 2009

This paper presents the numerical simulation results on the supercodnucting electrodynamic suspension (EDS) simulator according to the variation of the ground conductor. The levitation force of the EDS system is formed by the reaction between the moving magnet and the fixed ground conductor. The possible way to simulate the EDS system were simulated in this paper by using finite element method (FEM). The static type simulator which consists of the fixed magnet, the fixed ground conductor and the ac current supply system. To verify the characteristics of high speed EDS system with the moving type simulator heavy, large and fast moving ground conductor is needed. The static type simulator can get the characteristics of the high speed EDS system by applying equivalent ac current to velocity, therefore it does not need large moving part. The static type EDS simulator, which can consist of an HTS magnet, the fixed ground conductor(s), an AC power supply and the measuring devices, also test the effect of the shape of the ground conductor easily. The plate type ground conductor made stronger levitation force than ring type ground conductor. Although the outer diameter 335 mm ring type ground conductor (Ring3) was larger than the outer diameter 235 mm ground conductor (Ring2), the levitation force by Ring2 was stronger than that by Ring3. From the calculation results on this paper, the consideration of the magnetic flux distribution according to the levitation height should be included in the process of the ground conductor design.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.682-684
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• 2002

There is much room for consideration that the magnet design of UTM. When the vehicle runs 60mR curved line on test track, the ratio of cross section area changed to cross the magnet pole and rail. The ratio is reduced about 20% of the total magnet on one bogie. Therefor, magnet current is increased about 3.5A to maintain constant air gap. This paper suggest to margin of the magent design is 1.1 rather than rated levitation force.