• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.11a
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• pp.213-216
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• 2007

The computer simulation for the fault current limiting characteristics of the superconducting fault current limiter (SFCL) using the magnetic coupling of two coils was performed. The magnetic fluxes generated from two coils were canceled out during a normal time. However, the resistance generation of high-$T_c$ superconducting (HTSC) element after a fault occurrence keeps up the magnetic fluxes of two coils and contributes to the fault current limiting operation. Through the computer simulation for the fault current limiting characteristics based on its electrical equivalent circuit, its operational current and the limiting impedance could be improved by adjusting the inductance ratio between two coils.

• The Transactions of the Korean Institute of Power Electronics
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• v.6 no.6
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• pp.474-480
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• 2001

In this paper a low signal reduction communication system that does not use the communication line but power line is presented It will be very useful for an information-oriented society with tele-metering and home automation. The conventional system has a difficulty in transmitting information due to decreasing communication voltage. The proposed system employs a special type switching amplifier system which has a low inner resistance and uses high efficient ferrite core in coupling circuit. This new system is proposed to reduce the loss of conductor load and coupling circuit in a PLC system.

• Proceedings of the KIEE Conference
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• 2007.04c
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• pp.68-70
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• 2007

The operational characteristics of superconducting fault current limiter (SFCL) using magnetic coupling of coils were investigated. This SFCL consists of a high-Tc superconducting (HTSC) element and two coils with series or parallel connection on the same iron. This SFCL has the merit that the operational current of SFCL can be increased higher than the critical current of the superconducting element by adjusting the inductance ratio between two coils. To confirm its operation, the circuit for the fault simulation was constructed. From the measured voltage and current of the SFCL, it was confirmed that the resistance of HTSC element comprising this SFCL increased more than that of HTSC element's independent operation.

• Textile Coloration and Finishing
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• v.16 no.2
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• pp.15-24
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• 2004

The antibiotic reactive dye was synthesized by coupling of reactive chromagen with diazotised silver sulfadiazine for an antibiotic property. The highly reactive MCT(monochlorotriazine) and DCT (dichlorotriazine) type functional groups which have heterocyclic ring and moderately reactive VS-type dye that has good dyeability were used for reactivity. The synthesized antibiotic reactive dye is expected to impart the antibiotic function with high durability on cotton fabric only by one-step dyeing process without further finishing treatment. The synthesis of antibiotic dye was easily proceeded thorough diazotisation of silver sulfadiazine and coupling with suitable chromogen. The dyeability of synthesized dye for cotton fabrics was excellent and the dyed fabrics showed good level of lightfastness, resistance to washing and rubbing. The antibiotic tests revealed that the dyed cotton fabrics with the synthesized dye had very good antibiotic properties.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.04a
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• pp.7-10
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• 2002

We designed the flyback planar transformer, which had 8W capacity, with 70V input voltage and 8.2V output voltage for the establishment of design method and the confirmation of application possibility. The numerical value of inductance measured under the switching frequency of 120 kHz was 1650 ${\mu}H$, which was the inductance efficiency of 85~87% against theoretical value. The A.C. resistance of primary and secondary coil was 4.2 ${\Omega}$ and 0.25 ${\Omega}$ respectively. On the other hand, the quality factor for each wound numbers showed quite a high value of 158 and 75 respectively. And the Coupling Factor was 0.96~0.97 under 120 kHz switching frequency. And the shape of the output wave of the planar transformer at 70V input voltage was a stable square wave.

• Elastomers and Composites
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• v.30 no.2
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• pp.112-121
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• 1995

The physical properties of rubber compounds containing silica and siliane coupling agent in order to replace the carbon black and prepare for environmental regulation showed improved dynamic properties(rebound, heat build-up, $60^{\circ}C\;tan\;{\delta}$), but the abrasion resistance did not improve compared with the compounds containing carbon black. Also, curing retardation because of coherent structure of silica improved by the addition of DEG, but the mixing step change of activators did not so much improve the static and dynamic properties of the compounds containing high synthetic rubber, the status of mixing and dispersion showed that the compounds containing carbon black was much better than the compounds containing silica by TEM investigation.

• Transactions on Electrical and Electronic Materials
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• v.12 no.4
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• pp.140-143
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• 2011

The growth and characterization of $In_{0.5}Ga_{0.5}As/In_{0.5}Al_{0.5}As$ narrow-gap inverted high electron mobility transistor structures, developed as a candidate material for spin-injection devices, are presented in this study. We have grown samples possessing surface $In_{0.5}Ga_{0.5}As$ channels of different thicknesses (30 nm and 60 nm) both with and without a thin 3 nm $In_{0.5}Ga_{0.5}As$ cap layer by using molecular beam epitaxy. We then investigated the in-plane transport properties as well as the Rashba spin-orbit coupling constant of the two-dimensional electron gas confined at the heterojunction interface.

• Proceedings of the KIPE Conference
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• 2001.07a
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• pp.471-474
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• 2001

In this paper, a communication system that is not using the communication line but power line is presented. It will be very useful for an information-oriented society with tole-metering and home automation. Conventional system has a difficulty in transmitting information due to decreasing communication voltage. Proposed idea is a special type switching amplifier system which has a low inner resistance and using high efficient ferrite core in a coupling circuit. This new system is proposed to overcome the loss of conductor load and coupling circuit in a PLC system.

• Proceedings of the KIEE Conference
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• 2006.07e
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• pp.87-88
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• 2006

There are a number of reported instances of actual pipeline rupture during power line faults caused by melting of the pipe wall. This type of hazard was considered to be among the most serious of AC effects on pipelines in an international survey, comparable to the personnel safety hazard. Moreover, resistance coupling is not only a risk when the pipeline parallels a power line but also when they cross. One method of minimizing the effects of resistive coupling is by maintaining an appropriate separation distance between the pipeline and tower. This paper investigate the experiment for separation distance between the powerline earth and pipelines.

• Bulletin of the Korean Chemical Society
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• v.6 no.4
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• pp.210-214
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• 1985

Urokinase, a plasminogen activator, was conjugated with dextran by the cyanogen bromide activation-coupling method. The resulting water-soluble conjugate was purified by gel permeation chromatography on Sephadex G-200. The maximal activity was obtained when the ratio of urokinase/dextran was 1/20 for the coupling. The final preparation showed 5 CTA units/mg conjugate, 300 CTA units/mg protein, 8.4 % activity retention, and 47 % protein retention. The urokinase-dextran conjugate had good thermal, pH and storage stabilities. In addition, it showed greater resistance to the inhibitory effect of human plasma than native urokinase. Also in vitro biological half-life of urokinase increased 40 times by this conjugation. In view of activity, excellent stability and increased half-life, the conjugate can be a potential fibrinolytic agent in an injectable form.