• Korean Journal of Acupuncture
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• 제17권1호
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• pp.173-177
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• 2000

We have observed the electrical resistance of every point in a $16{\times}64$ matrix that is projected to the medial side of human forearm. The electrical resistance against the 1.25V directing current was rated in discrete scale and illustrated in contour maps. The characteristics of distribution of electrical resistance and it's relations to so called Meridians were also discussed.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1080-1085
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• 2003

The flow of electrical current through a microscopic actual contact spot between two conductors is influenced by the flow through adjacent contact spots. A smoothed version of this interaction effect is developed and used to predict the contact resistance when the statistical size and spatial distribution of contact spots is known. To illustrate the use of the method, an idealized fractal rough surface is defined using the random midpoint displacement algorithm and the size distribution of contact spots is assumed to be given by the intersection of this surface with a constant height plane. With these assumptions, it is shown that including finer scale detail in the fractal surface, equivalent to reducing the sampling length in the measurement of the surface, causes the predicted resistance to approach the perfect contact limit.

• 조명전기설비학회논문지
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• 제24권10호
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• pp.85-89
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• 2010

During a ground fault the maximum fault current and neutral to ground voltage will appear at the pole nearest to the fault. Distribution lines are consisted of three phase conductors, an overhead ground wire and a multi-grounded neutral line. In this paper phase to neutral faults were staged at the specified concrete pole along the distribution line and measured the ground fault current distribution in the ground fault current, three poles nearest to the fault point, overhead ground wire and neutral line. A effect by grounding resistance of poles of ground fault current in the 22.9[kV] multi-ground distribution system. by field tests.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2004년도 학술대회 논문집
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• pp.293-295
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• 2004

Public utilities adopt the grounding rules ; class I, class II, class III and special class III, and install the grounding electrodes in distribution facilities. To keep the safety of the human and the facilities, Public utilities also manage the value of ground resistance in distribution system biennially. At present the Hook-On meter is normally used to measure the ground resistance although it has ${\pm}5[%]$ measuring error and it can not measure the exact value when the current is over 1[A]. In addition it is very difficult to use the fall-of-potential method in distribution system. In this paper we propose the new measurement method using ground current of distribution system as the current source.

• KIEE International Transactions on Electrophysics and Applications
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• 제4C권2호
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• pp.68-72
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• 2004

The performance of copper-tungsten for electrodes used in an ultra high voltage interruption system was evaluated by means of an interruption test, which requires a large-scale apparatus and high cost. In this study, prior to the interruption test, the characteristics of a Cu-W electrode were estimated through the DC arc test, which is a simple, low cost procedure. The DC arc characteristics of a 20wt%Cu-80wt%W electrode were investigated with the change of tungsten powder size distribution and the addition of nickel. In specimens containing a high volume fraction of large sized tungsten particles, the relative density and hardness of sintered Cu-W electrodes increased while the electrical conductivity and the DC arc resistance decreased. Furthermore, the relative density became enhanced with the increase of the amount of nickel while the hardness and electrical conductivity diminished and the DC arc resistance worsened.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 C
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• pp.1188-1191
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• 1998

Detailed estimation of subsurface resistivity distribution and accurate estimation of actual fault current coming into the grounding system are indispensible to optimun grounding system design. Especially, it is essential for efficient grounding design to estimate subsurface resistivity distribution quantitatively and logically. Accurate estimation of subsurface resistivity distribution has an absolute influence on calculating touch voltage, step voltage and ground potential rise (GPR) which are related with grounding design standard for human safety. In this study, thirty-three electrical sounding surveys were made in Yongdam Power Station to obtain detailed subsurface resistivity distribution and the sounding data were interpreted quantitatively using multi-layered model. The results of the quantitative resistivity models were adopted practically to calculate grounding resistance values. Analytical asymptotic equations and CDEGS program were used in grounding resistance calculation and the results were compared and reviewed in the study.

• 전기학회논문지P
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• 제66권4호
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• pp.219-223
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• 2017

In this paper, we calculated the losses in the high voltage lines of power distribution system. The losses caused by high voltage lines are calculated using maximum current, resistance, loss factor, and dispersion loss factor. The accurate extraction of these factors are very important to calculate the losses exactly. Thus, the maximum loads are subdivided to regions and calculated monthly for more accurate maximum current calculation. Also, the composite resistance is calculated according to the ratio of the used wire types. In order to calculate the loss factor, the load factors according to the characteristics of each region were calculated. Finally, the losses of the distribution system is calculated by adding the losses by the transformers and the low voltage lines.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.404-409
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• 2004

The electrical contact resistance is here estimated using the multiscale microcontact distribution of elastic contact between rough surfaces, simulated from the Archard's model, and the electrical contact conduction theory suggested by Greenwood. These analysis confirms that the electrical contact resistance is converged to a values, larger than would be obtained if the contact spots were widely separated and hence independent. In multiscale process, the base potential is close to the value of the potential difference between the contact surface and the extremity of body, suggesting a possibility to obtain the multiscale electrical contact resistance relations.

• Journal of Electrical Engineering and Technology
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• 제8권6호
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• pp.1365-1370
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• 2013

This paper examines the effects of magnetic induction attenuation on current distribution in the exit regions of the Faraday-type, non-equilibrium plasma Magnetohydrodynamic (MHD) generator by numerical calculation using cesium-seeded helium. Calculations show that reasonable magnetic induction attenuation creates a very uniform current distribution near the exit region of generator channel. Furthermore, it was determined that the current distribution in the middle part of generator is negligible, and the output electrodes can be used without large ballast resistors. In addition, the inside resistance of the exit region and the current concentration at the exit electrode edges, both decrease with the attenuation of magnetic flux density. The author illustrates that the exit electrodes of the diagonal Faraday-type, non-equilibrium plasma MHD generator should be arranged in the attenuation region of the magnetic induction, in order to improve the electrical parameters of the generator.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2002년도 학술대회논문집
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• pp.125-131
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• 2002

It is very important to assume potential distribution to be generated in electrode environs and grounding resistance by current beforehand, when incoming at grounding electrode to plan efficient grounding facilities In this paper, we analyzed grounding resistance through a simulation experiment by a water tank scaled model electrode of the rectangular earth plate, a theoretical Calculation result of the rectangular earth plate and measurement of grounding resistance buried rectangular earth plate analysing earth surface potential.