• Proceedings of the KIEE Conference
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• 2000.11b
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• pp.355-357
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• 2000

Measurement used electricsal sounding(MacOHM 2115, Japan) for grounding resistance of Jung-Bu highway Ha-Nam IC about 500m. To applied measurement method is fall of potential method and analysis earth resistivity used ESII(Electrical Sounding Interactive Interpretation) program. This result propose for construction plan of electric corrosion.

• Economic and Environmental Geology
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• v.46 no.2
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• pp.105-121
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• 2013

This study introduces integrated approach on detection of a leakage in a sea wall based on remote sensing, electric resistivity survey, electromagnetic survey, and borehole survey for the Seosan A-Region sea wall. The satellite temperature distribution from Landsat ETM+ data identifies water leakage distribution and period by analyzing temperature mixing patterns between sea water and fresh water. Electric resistivity survey provides both horizontal and vertical anomaly distributions over the sea wall showing below average electric resistivity. Electromagnetic survey(electrical conductivity survey) reveals the potential possible leakage areas with minimal background impact by comparing electrical conductivity values between high and low tides. Borehole image processing system confirmed the locations of anomalies identified from the other survey methods and distributions of vertical fracture zones. The integrated approach identified 41.7% of the sea wall being the most probable area vulnerable to water leakage and effectively approximated both horizontal and vertical distribution of water leakage. The integrated analysis of remote sensing, electric resistivity survey, electromagnetic survey and borehole survey is considered to be an optimal method in identifying water leakage distribution, period, and extent of fractures knowledged from the boreholes.

• Journal of Advanced Navigation Technology
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• v.10 no.2
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• pp.152-158
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• 2006

In this paper, electromagnetic scattering problems by a resistive strip grating with zero resistivity at the strip-edges on a grounded 2 dielectric layers according as strip width and spacing, relative permittivity, thickness of dielectric layers, and incident angles of a electric wave are analyzed by applying the FGMM(Fourier-Galerkin Moment Method) known as a numerical procedure. The scattered electromagnetic fields are expanded in a series of floguet mode functions. The boundary conditions are applied to obtain the unknown field coefficients and the resistive boundary condition is used for the relationship between the tangential electric field and the electric current density on the strip. The tapered resistivity of resistive strips varies zero resistivity at strip edges. Then the induced surface current density on the resistive strip is expanded in a series of Chebyshev polynomials of the second kind. The normalized reflected power with zero resistivity in this paper show in good agreement with those of existing paper.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.703-705
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• 2005

접지설계에 있어서 토양의 전기적 특성은 접지극의 형상과 더불어 가장 중요한 설계요소 중 하나이며 이러한 토양의 전기적 특성은 접지극이 매설될 지역의 고유한 저항률, 즉 고유저항률(specific earth resistivity)로 대표되어 왔다. 이처럼 고유저항률에 근거한 수작업 접지설계는 복잡한 구조와 특성을 갖는 실제 토양을 균일한 매질로 등가화하는 절차를 필요로 한다. 본 논문에서는 미얀마 500 kV 송전철탑 수작업 접지설계를 위하여 수평다층토양을 균일매질로 등가화하는 절차를 제시하였다.

• Journal of Sensor Science and Technology
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• v.24 no.5
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• pp.348-352
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• 2015

Thin nickel oxide films formed on uncooled and cooled $SiO_2/Si$ substrates using a radio frequency (RF) magnetron sputter powered by 200 W in a mixed atmosphere of argon and oxygen. Grazing-incidence X-ray diffraction and field emission scanning electron microscopy are used for the structural analysis of nickel oxide films. The electrical conductivity required for better bolometric performance is estimated by means of a four-point probe system. Columnar and (200) preferred orientations are discovered in both films regardless of substrate cooling. Electric resistivity, however, is greatly influenced by the substrate cooling. Oxygen partial pressure increase during the nickel oxide deposition leads to a rapid decrease in resistivity, and the resistivity is higher in the cooled nickel oxide samples. Even when small microstructure variations are applied, lower resistivity in favor of low noise performance is acquired in the uncooled samples.

• Journal of Advanced Navigation Technology
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• v.15 no.3
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• pp.349-354
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• 2011

In this paper, H-polarized scattering problems by a resistive strip grating with zero resistivity at strip-edges over a grounded dielectric plane according to the strip width and grating period, the relative permittivity and thickness of a dielectric layer, and incident angles of a transverse electric (TE) plane wave are analyzed by applying the Fourier-Galerkin Moment Method (FGMM). The tapered resistivity of resistive strips has zero resistivity at strip edges, then the induced surface current density on the resistive strip is expanded in a series of Chebyshev polynomials of the second kind as a orthogonal ploynomials. The sharp variations of the reflected power are due to resonance effects were previously called wood's anomallies, the numerical results for the reflected power are compared with those of uniform resistivity in the existing papers.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2004.11a
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• pp.241-245
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• 2004

The electric safety tends to be more important according to electric facilities's increase and its use in these days. This paper analyzes soil resistivity of two areas in the country using CDEGS(Current Distribution, Electromagnetic Interference, Grounding and Soil Structure, Canada). We designed rod and mesh grounding system and made a comparative study of ground resistance, GPR(Main Electrode Potential Rin), step voltage and touch voltage. Then we could analyz only the safety but also economical efficiency in elocution of grounding. As a result of simulation, ground resistance, GPR(Main Electrode Potential Rise), step voltage and touch voltage became higher in proportion to soil resistivity. Therefore we expect to estimate the propriety of grounding system design through accumulation and analysis of data in consideration of characteristics of soil.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.2
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• pp.255-261
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• 2003

It is advantageous to use NDE methods to assess the mechanical properties of materials since the conventional method is time-consuming and sometimes requires cutting of sample from the component. The NDE parameters such as ultrasonic velocity and attenuation, electric resistivity, and magnetic coercive force and remanance have been utilized to evaluate changes of material properties due to heat treatment condition. It has been found that changes of materials properties under quenched and tempered/PWHT treatments could not be detected using EMAT and Electrical resistivity methods. However, victors hardness and magnetic hysteresis loop decreased with heat treatment procedures. These results were obtained using 3Cr-lMo-0.25V steel. The magnetic parameters were found to be most sensitive to changes of material properties.

• 한국지구물리탐사학회:학술대회논문집
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• 2007.06a
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• pp.291-296
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• 2007

We measured potential waveform of load, displacement, micro electric signal generated by rock and mortar fracture using PXI A/D Converter. The rock type used for measurement was used granite, limestone and sandstone, and mortar specimen. we made measuring equipment of physical properties to confirm basic information of physical properties, measured physical properties of rock engineering, electric resistivity and seismic velocity. Potential waveform system was built using PXI A/D Converter and measured potential waveform of load, displacement, micro-electric signal generated using this during uniaxial compressive test by the specimen finished such test of physical properties. Using the saturated rock and mortar specimen, micro electric signal increased, and It didn't increase a signal in dried rock and mortar specimen according as load and strain rate increases. But signal also increased in saturated or dried specimen in case of sandstone. It was possible to check the close correlation relationship the signal and fracture behavior by a compressive load as the signal of fracture position was increased bigger than the other position. It was also possible to check the correlation relationship between physical properties and micro geo-electric signal.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.6
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• pp.108-114
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• 2011

In order to mitigate the possible hazards from electric shock due to the touch and step voltages, the high resistivity material such as gravel is often spread on the earth's surface in substations. When the grounding electrode is installed in two-layer soil structures, the surface layer soil resistivity is different with the resistivity of the soil contacted with the grounding electrodes. The design of large-sized grounding systems is fundamentally based on assuring safety from dangerous voltages within a grounding grid area. The performance of the grounding system is evaluated by tolerable touch and step voltages. Since the floor surface conditions near equipment to be grounded are changed after a grounding system has been constructed, it may be difficult to determine the tolerable touch and step voltage criteria. In this paper, to propose an accurate and convenient method for evaluating the protective performance of grounding systems, the propriety of the method for evaluating the current flowing through the human body around on a counterpoise buried in two-layer soils is presented. As a result, it is reasonable that the grounding system performance would be evaluated by measuring and analyzing the current flowing through the human body based on dangerous voltages such as the touch or step voltages and the contact resistance between the ground surface and feet.