• KIEE International Transactions on Power Engineering
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• 제5A권4호
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• pp.350-356
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• 2005

Earth equipments are essential to protect humans and other types of equipment from abnormal conditions. Earth resistance and potential must be restricted within a low value. An estimation algorithm of earth parameters and equivalent resistivity is introduced to calculate reliable earth resistance in this research. The proposed algorithm is based on the relationship between apparent resistances and earth parameters. The proposed algorithm, which approximates the non-linear characteristics of earth by using the Artificial Neural Network (ANN), estimates the earth parameters and equivalent resistivity. The effectiveness of the proposed method is verified with case studies.

• 조명전기설비학회논문지
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• 제27권2호
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• pp.95-101
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• 2013

This paper presents the comparison of the earth resistivity obtained from the measurements made with the three-electrode and four-electrode fall-of-potential techniques. The ${\rho}-a$ curve obtained from Wenner four-electrode method in undisturbed earth is in good agreement with the ${\rho}-l$ curve obtained from the three-electrode method based on the fall-of- potential method. However, The ${\rho}-a$ curve in disturbed earth with moisture and freezing is significantly different with the ${\rho}-l$ curve. The ${\rho}-a$ curve is considerably sensitive to the freezing and the moisture present in the earth surface compared to the ${\rho}-l$ curve. Thus to determine the actual earth resistivity, it is necessary to take into account the earth surface conditions when measuring the earth resistivity.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.563-565
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• 2005

In this study, a algorithm to estimate Equivalent earth resistivity and Earth parameter using Artificial Neural Network(ANN) was proposed. Structures of the soil are grouped by using SOM algorithm before estimation. Earth parameter and Equivalent earth resistivity are obtained by using BP algorithm. The effectiveness of the proposed algorithm was verified. In the case study. afterwards, the algorithm proposed in this study will be used in more applications and gained more reliability.

• 조명전기설비학회논문지
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• 제25권6호
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• pp.68-74
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• 2011

The touch or step voltages which exist in the vicinity of a grounding electrode are closely related to the earth structure and resistivity and the ground current. The grounding design approach is required to determine the grounding electrode location where the hazardous voltages are minimized. In this paper, in order to propose a method of mitigating the electric shock hazards caused by the ground surface potential rise in the vicinity of a counterpoise, the hazards relevant to touch voltage were evaluated as a function of the soil resistivity ratio $\rho_2/\rho_1$ for several practical values of two-layer earth structures. The touch voltage and current on the ground surface just above the test electrode are calculated with CDEGS program. As a consequence, it was found that burying a grounding electrode in the soil with low resistivity is effective to reduce the electric shock hazards. In the case that the bottom layer soil where a counterpoise is buried has lower resistivity than the upper layer soil, when the upper layer soil resistivity is increased, the surface potential is slightly raised, but the current through the human body is reduced with increasing the upper layer soil resistivity because of the greater contact resistance between the earth surface and the feet. The electric shock hazard in the vicinity of grounding electrodes is closely related to soil structure and resistivity and are reduced with increasing the ration of the upper layer resistivity to the bottom layer resistivity in two-layer soil.

• International journal of advanced smart convergence
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• 제9권3호
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• pp.97-104
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• 2020

In this paper, we propose a method to derive the kernel function directly from the measured apparent earth resistivity. At this time, the kernel function is obtained through the process of solving a nonlinear system. Nonlinear systems with many variables are difficult to solve. This paper also introduces a method for converting nonlinear derived systems to linear systems. The kernel function is a function of the depth and resistance of the Earth's layer. Being able to derive an accurate kernel function means that we can estimate the earth parameters i.e. layer depth and resistivity. We also use various Earth models as simulation examples to validate the proposed method.

• 조명전기설비학회논문지
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• 제19권6호
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• pp.22-28
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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 등가 화하는 절차를 필요로 한다. 본 논문에서는 미얀마 500[kV] 송전철탑 수작업 접지설계를 위하여 수평다층토양을 균일 매질로 등가화 하는 절차를 제시하였다.

• 한국지능시스템학회논문지
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• 제22권4호
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• pp.454-459
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• 2012

Wenner의 4전극법으로 측정한 겉보기 대지저항률을 이용하여 대지저항률의 Kernel 함수를 추정할 수 있다. 이 때 커널함수를 추정하는 것은 비선형시스템을 푸는 과정으로 유도된다. 그러나 변수가 많은 비선형시스템은 해를 구하기가 쉽지 않다. 본 논문은 이 비선형시스템을 선형화하여 커널함수를 추정하는 방법을 제시한다. 마지막으로 제안한 방법을 평가하기 위하여 다양한 구조로 된 대지모델들을 시뮬레이션의 예로 사용한다.

• 대한전기학회논문지:전력기술부문A
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• 제51권2호
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• pp.76-82
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• 2002

This paper presents the method of sail-resistivity estimation using the backpropagation(BP) neural network. Existing estimation programs are expensive, and their estimation methods need complex techniques and take much time. Also, those programs have not become well spreaded in Korea yet. Soil resistivity estimation method using BP algorithm has studied for the reason mentioned above. This paper suggests the method which differs from expensive program or graphic technology requiring many input stages, complicated calculation and professional knowledge. The equivalent earth resistivity can be presented immediately after inputting apparent resistivity through the personal computer with a simplified Program without many Processing stages. This program has the advantages of reasonable accuracy, rapid processing time and confident of anti users.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.223_224
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• 2009

This paper investigates a normal induced voltage according to earth resistivity from distribution lines using calculation method of the normal induced voltage on telecommunication line. The induced voltage according to earth resistivity from distribution lines is verified by vector analysis and EMTP(Electro-Magnetic Transients Program).

• 전기학회논문지P
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• 제62권4호
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• pp.186-191
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• 2013

Earth equipments are essential to protect ITS facilities from abnormal situation. In this research, an estimation algorithm of earth parameters and equivalent resistivity is introduced. Traditional estimation methods can be divided into graphic method and numerical method. The result of graphic method is varied by the ability of expert or repeated calculation and it is hard to estimate the parameters precisely. The numerical method requires special techniques such as optimizing theory, and numerous calculations, whose results can be varied with initial values. The proposed algorithm is based on the relationship between apparent resistances and earth parameters and approximates the nonlinear characteristics of earth using ANN(artificial neural networks). The effectiveness of proposed method is verified in case studies.