• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.2
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• pp.127-129
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• 1988

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.54 no.1
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• pp.31-37
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• 2005

With biological effects by ELF(Extremely Low Frequency) magnetic field generated from power system, the transient magnetic field from electric appliances is a major issue presently. In this paper, we measured magnetic field distributions around electric appliances in view of harmonics and analyzed them by the use of an equivalent magnetic dipole moment method. This method was applied to 19 types of appliances, and their equivalent magnetic dipole moments and harmonic components were determined. The results show that this method is applicable to many appliances and the higher frequency magnetic field may induce higher current inside living bodies.

• Journal of the Korean Magnetics Society
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• v.18 no.6
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• pp.221-224
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• 2008

This paper describes the equivalent dipole modeling method utilizing a singular value decomposition technique from analysis data by the FNREMUS Detailled Modeller software based on BEM which can predict the underwater electric field signal due to a galvanic corrosion phenomenon on a naval vessel. The proposed dipole modeling method was successfully verified in good agreement with predicted BEM data at 30 m depths through the comparison of average differences. The proposed dipole modelling method can be effectively used in the prediction and analysis of static electric field signature distributions generated from a naval vessel at any different depths.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.7 no.2
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• pp.105-116
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• 1996

The design and analysis of the transversely fed EMC(electromagnetically coupled) microstrip dipole have been accomplished by using the integral equation and MOM(method of moment)in frequency domain in order to find the current distribution of the dipole. In this study, we proposed the possibilities for design and analysis of EMC micro-strip dipole array antenna by means of calculating the current distribution of each dipole directly using the FDTD(finite difference time domain) method. In this case, we applied the formulation which is the finite difference expression of the Maxwell's integral equation. From the current distribution of each dipole, we calculated the far field electric component and showed that the calculation process and running time was reduced with respect to the method which calculates the radiation field with surface electric and magnetic current density.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.15 no.9
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• pp.841-847
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• 2004

EMI emission characteristics of 42" AC-PDP panel are investigated in this paper. First, EMI emission source was modeled the scan electrode and the sustain electrode to a simple electric and magnetic dipole type radiator. Second, EMI emission source was modeled as reconfigured the scan electrode and the sustain electrode. The primary source of EMI emission was investigated using FEM calculation of the wave impedance and 3 dB beam width. The third. the EMI emission level was estimated using the measured sustain electrode current. Also, EMI emission level of 42" AC-PDP was measured. The results show that the calculated EMI emission level from the simple electric dipole model was shown to agree with that from the corresponding FEM simulation.

• Proceedings of the KSMRM Conference
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• 2002.11a
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• pp.76-76
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• 2002

Purpose： The purpose of this study is to optimize the configuration of body RF coil composed of 4 planar subcoils for low field open MRI. Method： Our low field RE coil is composed of 4 subcoils assumed to be located at both the bottom and top sides of permanent magnet. Each subcoils has 3 main strips. The coil system has mirror inversion symmetry. First, the currents on the strips are obtained by inductance calculation and circuit analysis, Second, all the strips are divided into line strip elements across the strips, the self Inductances of line strip elements and the mutual inductances among the line strip elements are calculated, and current distributions of strip are obtained by circuit analysis, where each strip is considered as parallel combination of line strip elements. Finally all the line strip elements are segmented, magnetic field has been calculated by pseudo electric dipole radiation method, where the current elements are regarded as pseudo electric dipole radiation sources. We have performed above procedures for various configurations of RE coil. The field homogeneity is calculated in the 25 cm DSV.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.961-965
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• 2009

Using much electric resistivity survey to design or preservation administration of facilities. However, By survey method that electric resistivity survey grasps special quality in base by potential difference creating artificial current in underground, Is influenced in electric resistance propensitys of various underground utilities in base. This Study selects dam 1 place that could grasp well underground situation and studied electricity interference effect by effect of underground utilities. Grasp underground utilities of dam interior, and control and observed accuracy with survey wave because various pole space. Through this Study, wish to present survey method of electric resistivity survey at design or survey of preservation administration dimension after with drawn result.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.28 no.5
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• pp.391-399
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• 2017

At present the general trend of modern electronics is toward smaller packages and high performance. As an antenna requires high powers, the EMC(Electromagnetic Compatibility) problems of the transmission line stage is becoming crucial day by day. In this paper, a transmission line excited by the electromagnetic fields from an infinitesimal electric dipole antenna is analyzed using the modified telegrapher's equations. The analytical equations are derived for arbitrarily positioned electric dipole with reference to a transmission line. To verify our approach, the induced voltage and current at the terminal were computed by the proposed approach and compared with those obtained by the electromagnetic simulation solver. Furthermore, the induced currents at the terminal of a transmission line excited by the electric dipoles at various positions were investigated using our approach.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.12
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• pp.1690-1698
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• 2018

Recent advances in ICT technology have transformed many of our daily lives and attracted a lot of attention to personal health. Heart beat measurement that reflects cardiac activities has been used in various fields such as exercise evaluation and psychological state evaluation for a long time, but its utilization method is limited due to its differentiation from clinical electrocardiogram. Therefore, in this study, we could observe the change of the measured signal according to the change of the distance and the position of the measuring electrodes which are non-standard electrode configuration. Based on the electric dipole model of the heart, correlation with clinical electrocardiogram could be confirmed by synthesizing multiple surface potentials measured with a shorter electrode distance than standard one. From the electromagnetic point of view, the distance between the measuring electrodes corresponds to the distance that the electric potential by the cardiac electric dipole moves, and the electric potential measured at the body surface is proportional to the moving distance of the electric potential. Therefore, it is preferable to make the distance between electrodes as long as possible, and to position the measuring electrode close to the ventricle rather than the atrium. In addition, it was found that standard electrocardiographic waveforms could be synthesized by using arithmetic sum of multiple measuring electrodes due to the relationship of electrical dipole vectors, which is obtained by dividing and positioning a plurality of measuring electrodes on a reference electrode line, such as Lead-I, Lead-II direction. Also, we obtained a significant Pearson correlation coefficient ($r=0.9113{\pm}0.0169$) as a result of synthetic experiments on four subjects.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.28 no.3
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• pp.246-249
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• 2017

In this paper, we designed the 3-axis isotropic electric-field measurement probe using resistor-loaded short dipole with lumped chip resistors. The designed probe shows good isotropic characteristics as well as wideband and low sensitivity. The isotropic characteristics of ${\pm}0.39dB$ from 100 kHz to the 3 GHz band were derived and the reception sensitivity was 0.1 V/m. The frequency response is within 3 dB of the whole section, especially ${\pm}1.3dB$ from 150 kHz to 3 GHz, which is superior to the conventional electric field probe with short dipoles.