• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 1999.07a
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• pp.156-164
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• 1999

This paper shows that the configuration of power transmission lines currently in place is suitable on the basis of calculated magnetic field strengths. The magnetic fields were computed for typical current distributions on power transmission lines for electric railways, which are characterized by severe load fluctuations and phase distortions. The result of the numerical analysis are compared with th ELF guidelines of magnetic fields from several case studies. The final conclusion reached in that effects of the magnetic fields near power transmission lines for electric railways are not significant enough to cause a biological safety concern.

• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1393-1395
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• 1997

In order to investigate the interfacial effects on the aging of power cables, we analyzed recently failed cables using characterization techniques. In this study, some cables showed a convolution which can cause the concentration of electric field and carbonized impurities at the surface of insulation. Also there is a relation between the degree of cross- linking and volume resistivity. From the hot oil test, the sites of water tree and void coincided with each other.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.538-541
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• 2007

In this paper, with a bistable curve of the bistable chiral splay nematic liquid crystal (BCSN LC) device, we clarify how the twist-to-splay transition is achieved under a horizontal field. By a sufficiently high horizontal electric field, the bistable property becomes monostable. The transition can be achieved.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.266-267
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• 2006

We present a systematic study of the heating and pre-sintering behavior of porous copper powder metal compacts. We employ a TE102 single mode microwave system to position the samples in the separated electric field (E) or magnetic field (H) anti-node of the cavity. We observe significant differences in the heating, pre-sintering, and microstructure evolution of the samples due to the individual fields. We note that sample history (whether heated first in the E-field or H-field) greatly effects a difference in heating trends and subsequent heating behavior and does not appear to be solely a thermal process.

• Food Science of Animal Resources
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• v.35 no.6
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• pp.800-806
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• 2015

We investigated the effects of a pulsed electric field (PEF) treatment on microbial inactivation and the physical properties of low-fat milk. Milk inoculated with Escherichia coli, Saccharomyces cerevisiae, or Lactobacillus brevis was supplied to a pilot-scale PEF treatment system at a flow rate of 30 L/h. Pulses with an electric field strength of 10 kV/cm and a pulse width of 30 µs were applied to the milk with total pulse energies of 50-250 kJ/L achieved by varying the pulse frequency. The inactivation curves of the test microorganisms were biphasic with an initial lag phase (or shoulder) followed by a phase of rapid inactivation. PEF treatments with a total pulse energy of 200 kJ/L resulted in a 4.5-log reduction in E. coli, a 4.4-log reduction in L. brevis, and a 6.0-log reduction in S. cerevisiae. Total pulse energies of 200 and 250 kJ/L resulted in greater than 5-log reductions in microbial counts in stored PEF-treated milk, and the growth of surviving microorganisms was slow during storage for 15 d at 4℃. PEF treatment did not change milk physical properties such as pH, color, or particle-size distribution (p<0.05). These results indicate that a relatively low electric-field strength of 10 kV/cm can be used to pasteurize low-fat milk.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.12
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• pp.2225-2229
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• 2010

In this study, we have investigated the effects of space charge on the conduction current with the variation of applied time of electric field in polymer insulators. We had also improved the PEA method, and then we could measure a simultaneously the space charge and the conduction current in insulators under the DC electric field. From this experiment, we have known the variation of conduction current due to the existence of space charge in XLPE1 and XLPE2.

• Proceedings of the KSME Conference
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• 2002.08a
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• pp.503-506
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• 2002

Electrorheological fluids(ERFs) show a rapid and reversible increase in viscosity by applied electric field. It is called the electrorheological effect (ER effect). The reason for ER effect is the induction of an electric dipole in each particle, leading to the formation of clusters in the direction of the field, which resist fluid flow. Generally, the behavior of ER fluids has been modeled on those of Bingham fluids. But there are some differences between Bingham fluids and ER fluids. The visualization of ER fliuds are presented and ER effects by the forming, growing and breaking of clusters are discussed. In the low shear rate area, the pressure drop is measured by a pressure sensor and the formation of ER particles is visualized by video camera. The reason for the nonlinear behavior of ER fluids at low shear rate is explained through results of visualization.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.4
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• pp.826-834
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• 1994

The purpose of this study is to identify torque characteristics in capacitor type electric motors and to illustrate the effects of several design parameters on the fluctuating components of the motor torque. To do this, two revolving field theory and stationary reference frame theory were applied to derive governing equations for the torque generated by motor. For simulation studies, parameters of the motor components were measured under the conditions of no loading and locking. Based on these, effects of several design variables on the torque characteristics were analyzed and compared with the actual measurements, which were estimated indirectly by measuring the stator voltage and current. Then, some illustrative improvements in design are suggested by taking Taguchi method.

• Journal of Electrical Engineering and Technology
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• v.9 no.4
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• pp.1355-1359
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• 2014

In the proposed work a 2D analytical modeling of single halo Triple material Surrounding Gate (SH-TMSG) MOSFET is developed. The Surface potential and Electric Field has been derived using parabolic approximation method and the simulation results are analyzed. The essential substantive is provided which elicits the deterioration of short channel effects and the results of the analytical model are delineated and compared with MEDICI simulation results and it is well corroborated.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1512-1513
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• 2007

In this paper the influence of CMOS- and TTL-technology on the breakdown and destruction effects by artificial electromagnetic waves is determined. Different electronic devices(3 CMOS & 5 TTL) were exposed to high amplitude electromagnetic waves. CMOS ICs were occurred only destruction below the max electric field and TTL ICs were occurred breakdown and destruction below the max electric field. The SEM analysis of the destruction devices showed onchipwire and bondwire destruction like melting due to thermal effect. The test results are applied to the data which understand electromagnetic wave effects of electronic equipments.