• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.209-212
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• 1999

We studied the operating properties of resistive and inductive SFCLS with 100 $\Omega$ of quench impedance for a three-phase-fault in the 154 kV transmission system. The fault simulation at the phase angles 0$^{\circ}$ , 45$^{\circ}$ , and 90$^{\circ}$ showed that the resistive SFCL limited the fault current less than 16 kA without any DC component after one half cycle from the instant of the fault. On the other hand, the inductive SFCL suppressed the current below 11 kA, but with 3-4 kA of DC component which decreased to zero in 5 cycles. We concluded that the inductive SFCL had higher performance in current limiting but the resistive SFCL was better from the view point of DC components.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.4
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• pp.655-665
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• 2009

The purpose of this study is to find out the Korean fashion brand purchasing behavior of Chinese woman college students who would be the one of major customers in Chinese market along with their preferences of Korean wave and fashion leadership. The data was collected from 379 Chinese female college students on Qingdao, China. The results based on the data analysis were as follows. 1. The students's preferences for Korean wave about Korean drama, popular song, films were relatively high. 2. Chinese female college students's evaluation of Korean fashion brand was high, especially, for the fashion trend, design/style, color, cutting and sewing, fitting, and material. However, they valued that its price was expensive. 3. The fashion leadership was classified as fashion innovation or fashion opinion leadership. 9.0% of the respondents were fashion dual leaders who were fashion innovator and fashion opinion leader. 4. The higher family income of the respondents was the better fashion leadership, preferences for Korean wave, perceived quality and attitude toward Korean fashion brand. The results showed that promotion strategy focused on keeping the Korean wave through drama, films, and popular song. And the development of high fashion brand and the word of mouth marketing through fashion dual leader were also needed in order to make inroads into China market.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.24 no.3
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• pp.203-213
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• 1991

Zooplankton samples were collected vertically from different layers with a closing net at 14 stations in the middle East Sea of Korea in February, August and September to study distribution of biological indicators for analysis of water masses. Horizontal and vertical distributions of important species of copepods and chaetognathas known as indicator species were closely related to distributions of different water masses and oceanic fronts. Pleuromamma gracilis, Calanus tenuicornis, Sagitta enflata and Sagitta minima were found to be reliable indicator species to determine warm water mass with warm core, and Calanus cristatus, Calanus tonsus and Sagitta elegans could be used as cold water species for evaluating the movement of cold current from North Korea, and Gaetanus armiger was deep sea water species. Therefore, it was found that North Korean Cold Current down to the south along the coast appeared to be significant in the surface around Chumunjin area, and from here towards the south the cold water containing S. elegans submerged under warm water with S. enflata which were about $2{\~}4^{\circ}C$ higher than that of the vicinity and reappeared near Chukpeon area in surface layer. In the layer between loom and 300m depths, distribution of Pleuromamma gracilis and Sagitta bedoti indicated that warm water mass and front zone influenced by the different water systems were formed in northwestern area off Ulreung-do. In $300{\~}500m$ layer, the proper cold water could be estimated to be present in the northwestern area off Ulreung-do throughout the survey period by the high abundance of Gaetanus armiger. In August, distributions of S. bedoti, S. enflata and S. minima were valuable index to find oceanic fronts and warm core.

• 한국초전도학회:학술대회논문집
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• v.9
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• pp.214-217
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• 1999

We investigated the quench characteristics of meander line type resistive superconducting fault current limiters based on YBCO thin films grown on 2" diameter LaAlO$_3$ substrates. A gold layer was deposited onto the 0.4 ${\mu}$ m thick YBCO film to disperse the heat generated at hot spots, prior to patterning into 1 mm wide meander lines by photolithography. The limiters were tested with simulated fault currents of various amplitudes. The quench started at 10 A and was completed within 1 msec at the fault current of 65 A$_{peak}$. The dynamic quench characteristics were explained based on the heat conduction within the film and the heat transfer between the film and the surrounding liquid nitrogen. The heat transfer coefficient per unit area was estimated to be 3.0 W/cm$^2$K.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2002.02a
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• pp.368-370
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• 2002

We present current limiting properties of 1.2kV/70A superconducting fault current limiter based on YBCO thin films. This is consisted of 6 wafers (3 parallel $\times$ 2 serial connection) with 4 inch-diameter YBCO thin film. The quench current Iq of the switching elements vary between 33.9 and 35.6 A. Within the difference of 0.5 A in the sum of quench current Iq in two stacks, the serial connection of the stacks showed the simultaneous quench behavior in applied power of 1.2 kV/70A.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.05b
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• pp.141-144
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• 2002

We present current limiting properties of 1.2kV/70A superconducting fault current limiter based on YBCO thin films. This is consisted of 6 wafers (3 parallel ${\times}$ 2 serial connection) with 4 inch-diameter YBCO thin film. The quench current Iq of the switching elements vary between 33.9 and 35.6 A. Within the difference of 0.5 A in the sum of quench current Iq in two stacks, the serial connection of the stacks showed the simultaneous quench behavior in applied power of 1.2 kV /70 A.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.6
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• pp.505-510
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• 2001

We simulated the current limiting characteristics of a resistive superconducting fault current limiter (SFCL) for a single line-to-ground fault in the 22.9 kV system. The transient current during the fault increased to 6.33 kA, 5.80 kA and 3.71 kA without SFCL at the fault angles 0$^{\circ}$, 45$^{\circ}$ and 90$^{\circ}$, respectively, a resistive SFCL limited effectively the fault current to 2.27 kA in a half cycle without any DC components. The maximum quench resistance of an SFCL, 16Ω was suggested to be appropriate to limit the fault current in the 22.9 kV distribution system, considering the operating cooperation of a protective relay and the current limiting performance of an SFCL.

• Progress in Superconductivity and Cryogenics
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• v.7 no.1
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• pp.51-56
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• 2005

The recovery time of developing SFCL(Superconducting Fault Current Limiter) has an uncertainty. In general, the recovery time is estimated at 1 sec and more, even though the Process of SFCL technology is considered. However, auto reclosing time of circuit breaker is 0.3 sec in Korean power system. It is impossible to apply only one SFCL to power system because the recovery time is over the reclosing time of protection system. This study proposes two new SFCL systems for power system application. The proposed systems consider auto reclosing action for the protection in practical power system and consist of tow parallel SFCLS.

• 한국초전도학회:학술대회논문집
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• v.10
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• pp.268-271
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• 2000

We simulated the current limiting characteristics of a resistive SFCL with 16 ${\Omega}$ of resistance for a single line-to-ground fault in the 22.9 kV system. The transient current during the fault increased up to 6.33 kA, 5.80 kA and 3.71 kA without SFCL at the fault angles of 0${\circ}$,45${\circ}$ and 90${\circ}$, respectively. An resistive SFCL limited the fault current to 2.27 kA in a half cycle. The quench resistance of 16 ${\Omega}$ was suggested to be appropriate to limit the fault current in the 22.9 kV distribution system.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2000.02a
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• pp.91-94
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• 2000

We fabricated resistive super- conducting fault current limiters (SFCL) based on YBCO thin films grown on 2" diameter $Al_{2}O_{3}$ substrates. Two SFCLs with nearly identical properties. two SFCLs with nearly identical properties were connected in series to investigate simultaneous quenching. There was a difference of several half cycles in their quench starting time, although the difference was not more than 0.1 msec when they were operated separately. This imbalance was removed by connecting a shunt resistor to an SFCL in parallel. Increased power input at high voltages also reduced the initial imbalance in power dissipation. Further efforts on the simultaneous quench in SFCLs connected in series are on the way through methods such as the artificial control of quench speed.peed.