• Progress in Superconductivity
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• v.1 no.2
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• pp.99-104
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• 2000

The e.m.f. induced by a normal spot moving in a superconducting foil has been investigated by using the simulation and the experiment of a simple superconducting Power Supply. The induced e.m.f. has been derived theoretically from the magnetic field distribution within the spot. It is the sum of a DC component induced constantly by the Faraday's law during the spot's movement and a pulse component induced periodically by the flux conservation law at every electrical degrees 2$\pi$ radians. The DC component of the output voltage appears slightly nonlinear to the rotating speed, having values greater than the linear approximation values. The theoretical interpretation has been verified through experiment.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.4
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• pp.641-647
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• 2007

It has been said that Warehouse Management System(WMS) in e-Trade has considerably contributed to improvement of distribution industry. However, in the aspect of management we have many technical problems such as transportation due to tremendous demands of online data. Therefore, for Korea to be a hub of distribution and information, this is the best time to prepare the foundation of Supply Chain Management(SCM) under Enterprise Resource Planning (ERP) the and make a good use of WMS. The purposes of this study are presented as follows: First, it is to examine the general flow process of WMS in each field of our e-Trade Second, it is to present problems and plans of improvements involved in WMS in e-Trade. In short, this study aims at presenting interpretative foundation of WMS in a practical viewpoint, not presenting technical directions of WMS.

• Progress in Superconductivity and Cryogenics
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• v.6 no.2
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• pp.11-14
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• 2004

YBCO thin films have good characteristics for current limiting materials due to compact size and high current carrying capability. But the irregularities and the extreme thin thickness of YBCO films cause some difficulties in simultaneous quench and thermal shock protection. In order to solve these problems, vertical magnetic field generated from solenoid coil was applied to the YBCO element. And also to minimize the inductance caused by the serial connection of magnetic field source with superconducting elements, magnetic field source was separated from the power lines adapting protective current transformer. In this study, electric field-current (E-I) and quench characteristics of YBCO films were analyzed both by electrical measuring method and observations of bubble propagation. From the experiment results, it was revealed that the magnetic fields generated by surrounding coil could induce the uniform quench distribution for all stripes of current limiting units and finally simultaneous quenches were realized in all serial connection of YBCO elements. In addition, the separation of magnetic field source form electrical network could be good solution for simultaneous quench of YBCO films without any unnecessary effect caused by serial connection.

• Progress in Superconductivity
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• v.3 no.2
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• pp.252-256
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• 2002

We studied YBCO films for current limiting of the resistive type which utilizes a transition from superconducting to normal state caused by exceeding critical current. The films were deposited on sapphire substrates and covered by gold top layer. The current limiting element consists of 2 mm wide YBCO stripes connected in series. A serious problem in using YBCO films for current limiting is inhomogeneities caused by imperfect manufacturing. Therefore simultaneous quench is a difficult problem when elements for current limiting are connected in series. So some researchers have recently proposed using magnetic field and heating for simultaneous quench. We have measured extended exec trim field-current density(E-J) characteristics for current limiting elements of YBCO films in applied magnetic field of 0 - 130 mT. And we have investigated quench characteristics in current limiting elements and between elements of YBCO films in applied magnetic field. The result of the experiments show that the presence of applied magnetic fields induces uniform quench distribution fur the stripes in element at $50V_{rms}$, otherwise non-uniform quenches were observed. And simultaneous quenches between elements were investigated at $150V_{rms}$. We suggest that suppressing the critical current by increased fields due to fault current effectively forced the stripes of higher $J_{c}$(0) to quench, resulting in equalizing quench times.s.s.s.

• Proceedings of the KIEE Conference
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• 2005.11b
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• pp.116-118
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• 2005

IEC 60364-4-44 provides rules for the protection against the effects of conducted and radiated disturbances on electrical installations. Especially this standards deals with the protection of low voltage facility against the ground fault in the high voltage side of power distribution system. Many countries defines the regulations on the use and production of electrical facilities based on their own power system and technical references which are considered to be suitable for themselves. The background of circuit of IEC 60364 is based on the ungrounded system as most of European countries adopt. However, since domestic ground system is multi-grounding system different from European system, it is necessary to evaluate or prove the effect of the IEC 60364 for introducing and applying it to the domestic grounding system as a Korean standard. This paper presents the establishment of test field to get background data to introduce the IEC 60364 and to evaluate the standard is applicable or not to domestic rule for the protection against ground fault through the related test.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2001.02a
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• pp.102-103
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• 2001

In this paper we calculate the AC Loss in the superconducting slab carrying ac transport current. Magnetic diffusion equation for computation of the electric field and current distribution are based on Maxwell's equations and non-linear constitutive equation. The E-J characteristics of superconductor are applied to computation. We will present the result of the high-temperature superconductor case comparison with the slab of low temperature superconductor.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2006.11a
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• pp.127-134
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• 2006

Based on a weakly non-Gaussian theory the occurrence probability of freak waves is formulated in terms of the number of waves in a time series and the surface elevation kurtosis. Finite kurtosis gives rise to a significant enhancement of freak wave generation in comparison with the linear narrow banded wave theory. For fixed number of waves, the estimated amplification ratio of freak wave occurrence due to the deviation from the Gaussian theory is 50% - 300%. The results of the theory are compared with laboratory and field data.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.643-646
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• 2005

We present new ramp-reset waveforms that realize fast addressing in AC-PDPs. These waveforms distort the distribution of wall charges on the surface of a phosphor layer: hence, the enhanced electric field helps to ignite a cell faster. They also reduce the black luminance: the divide of erasing ramp down discharges into two parts, i.e. a surface discharge and a vertical discharge, makes lower luminance.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2117-2119
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• 1999

In this paper, the electric fields inside GIS with metal impurity is analysed by the use of 3 dimensional Surface Charge Method. We find the metal impurity makes electric field distribution inside GIS non-uniform and causes breakdown of $SF_6$ gas in GIS.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.10
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• pp.251-264
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• 2022

This study explores e-banking variables that affect client satisfaction in the Saudi Arabian banking industry spanning three dimensions: reliability, security concerns, and efficiency, which were chosen as predictors of customer satisfaction in the e-banking industry. A field survey using a self-administered questionnaire as a data collection instrument was adopted to collect the required data from a convenience sample of 250 participants of Saudi banking customers. The overall fit of the hypothesized model was tested using linear regression to find the rate of the independent factors' impact on the dependent variable. The study's findings revealed that there is a statistically significant relationship between the three dimensions and customer satisfaction in Saudi e-banking, with the largest impact being that of reliability, followed by efficiency, and finally security concerns. Also, the study found there was a significant difference in reliability which was considered more important for Saudis and there was a significant difference in efficiency, which was considered more important by males. The findings of this study suggest that these three dimensions are instrumental in e-banking customer satisfaction and that banks can gain a competitive edge by providing better services in these dimensions to sustain and develop their performance in the increasingly globalized banking industry.