• 대한기계학회논문집
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• 제15권6호
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• pp.1872-1885
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• 1991

본 연구에서는 자기장의 상호작용을 고려해야 하며 본 연구에서는 유한요소법 을 이용하여 전자기장 해석을 함으로써 이 문제를 해결하였다. 또한 여기서 계산된 자기압력을 이용하여 피가공재의 동적변형 거동을 유한요소법으로 해석하였다.

• 한국전자파학회논문지
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• 제11권5호
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• pp.839-848
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• 2000

본 논문은 전자파 장해 및 복사내성 측정에 사용되는 전자파 무반사실의 대용 방법으로 활용될 수 있는 전자파 잔향실의 전자기장 특성에 관하여 연구하였다. 체적이 동일한 직사각형 및 삼각형 구조의 잔향실 내부 필드균일성을 확보하기 위하여 Shroeder diffuser 방식을 적용하였으며, FDTD(Finite-Difference Time-Domain) 방법을 사용하여 잔향실 내부의 필드 특성을 조사하였다. 앞에서 언급한 두 가지 형태의 잔향실 내부에서 필드 특성을 조사하기 위해 시험공간 내의 75% 샘플을 가지고 분석하였다. 직사각형 잔향실의 경우 최대 $\pm$3dB, 삼각형 잔향실의 경우 최대 $\pm$4.4dB 내의 tolerance를 나타내었으며, 또한 직사각형 잔향실의 경우 편파에 대해서도 독립적이라는 결과를 얻을 수 있었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 C
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• pp.1670-1672
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• 2001

In compared with air insulated switchgear GIS has a high efficiency and confidence. Insulation method using $SF_6$ gas has a very excellent insulation characteristics for high voltage equipment but has a characteristics that insulation heredity is changed for internal unequal electric field. So analysis of electromagnetic field in GIS is very important basic data for structure design and trouble diagnosis process. In compared with established method, SNM in this paper observes variation of the electromagnetic field with real time and get result very similar to measurement. In order to know the variation of electromagnetic field distribution for transient response for time and position, variations are observed when metal particles are moving fast.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제51권2호
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• pp.68-73
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• 2002

In compared with air insulated switchgear, GIS has a high efficiency and confidence. Insulation method using $SF_6$ gas has a very excellent insulation characteristic for high voltage equipment but has a characteristic that insulation heredity is changed for internal unequal electric field. So analysis of time varying electromagnetic field in GIS is very important for structure design and trouble diagnosis process. In compared with established method, the SNM(Spatial Network Method) in this Paper can observe variation of electromagnetic field with real time and get result very similar to measurement. In order to Know variation of electromagnetic field distribution in fast moving particle, we make used of SNM.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집 특별세미나,특별/일반세션
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• pp.403-406
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• 2009

Recently, electricity is essential for human lives. Modem people take cultural benefits due to the development of the electric power system and the spread of the high tech-electric appliances, the cell phones, and etc. However, the electromagnetic field problems become prominent figures owing to the fault of the communication devices around the power line and the biological effect, and etc. In this paper, we introduce the simple electromagnetic field calculation based on the transmission line matrix method, prior to the analysis about the influence of electromagnetic field. Simulation object is the inner part of the trailer car in the high speed train. Unlike the existing paper we submitted, we analyze not only the magnetic field but the electric field in the inner part of the trailer car which makes up the high speed train.

• Journal of Magnetics
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• 제15권3호
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• pp.138-142
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• 2010

This paper reports the development of an analysis method in a synchronous reluctance motor (SynRM) using the finite element method (FEM) coupled with the electromagnetic field of the Preisach model, which represents an additional thermal source due to hysteresis loss and a thermal field. This study focused on thermal analysis relative to hysteresis and copper losses in a SynRM.

• 한국전자파학회지:전자파기술
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• 제3권2호
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• pp.3-9
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• 1992

The reponse of the angled two-strip transmission lines illuminated by an external electromagnetic field is estimated by using the circuit concept approach. Calculated terminal voltages reveal convergence to a fixed value as the number of discretization increases. The amplitude patterns of two terminal voltages to all the direction and polarization of the incident field are also calculated.

• 한국안전학회지
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• 제20권2호
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• pp.50-55
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• 2005

This Paper Presents assessment of fuzzy measure Possibility far the electromagnetic field according to voltage fluctuation of the Jechon Area. To cope with substantial electromagnetic analysis, the safety assessment were analyzed the double 154kV T/L, 345kV T/L, Jechon-Ichon Jechon-Youngju, respectively. As the results of case study, in case of 345kV T/L, the electric field value was 11.4927kV/m, magnetic field value was 0.4622G at the Point about 7m away from the line in severest case. Tn assessment of fuzzy measure Possibility for the electromagnetic field, this paper use probability of fuzzy and measure of fuzziness technique.

• 대한물리의학회지
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• 제7권3호
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• pp.349-356
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• 2012

Purpose : This study was designed to investigate the effects of pulsed electromagnetic field on functional recovery and expression of GAP-43 after incomplete spinal cord injury (SCI) in rats. Methods : To confirm the damage of SCI and effects of pulsed electromagnetic field, 20 Sprague-Dawley male rats were used and divided randomly 2groups (SCI, PEMF). Incomplete SCI was induced by using modified NYU drop model. After operation, functional recovery test, immunohistochemistry and western blot analysis were measured at 1, 2, 3 weeks. Pulsed electromagnetic field were apply three weeks (one times a day, five days a week and twenty minutes a session). Results : In the this study, applications of pulsed electromagnetic field after incomplete SCI induced the significant improvement in functional recovery and expression of neurotrophic factor. The results were as follows; Foot print test, PEMF were significantly decreased than the SCI (p<.05). Expression of GAP-43, PEMF were significantly increased than the SCI at 2 and 3 weeks (p<.05). Conclusion : In conclusion, pulsed electromagnetic field were positive effect in functional recovery and expression of GAP-43 after incomplete SCI in rats.

• 소성∙가공
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• 제17권1호
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• pp.35-45
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• 2008

Electromagnetic Forming (EMF) technology such as magnetic pulse forming, which is one of the high velocity forming methods, has been used for the joining and forming process in various industry fields. This method could be derived a series of deformation of sheet metal by using a strong magnetic field. In this study, numerical approach by finite element simulation of the electromagnetic forming process was presented. A transient electromagnetic finite element code was used to obtain the numerical model of the time-varying currents that are discharged through the coil in order to obtain the transient magnetic forces. Also, the body forces generated in electromagnetic field were used as the loading condition to analyze deformation of thin sheet metal workpiece using explicit dynamic finite element code. In this study, after finite element analysis for thin sheet metal forming process with free surface configuration was performed, analytical approach for a dimpled shape by using EMF was carried out. Furthermore, the simulated results of the dimpled shape by EMF were compared with that by a conventional solid tool in view of the deformed shape. From the results of finite element analysis, it is confirmed that the EMF process could be applied to thin sheet metal forming.