• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.569-571
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• 2005

In case of dead-tank circuit breaker with the earthed enclosure, the dielectric performance for phase to ground should be verified under the hot-gas condition produced by the current interruption. This test condition is required in breaking test duties with the rated short-circuit current and rated voltage. And, KERI has completed the reinforcement of the synthetic testing facilities and these facilities have the testing capacity which enables the full-pole testing for 800kV circuit breaker by adopting the series voltage injection method. So, this paper introduced the test circuit and procedures about the full-pole and the multi-part testing method which was devised to estimate the full -insulation of phase-to-ground for the multi-pole and dead-tank circuit breaker.

• Transactions on Electrical and Electronic Materials
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• v.5 no.4
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• pp.153-157
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• 2004

ITO thin films were deposited on PET and soda-lime glass substrates by a dc reactive magnetron sputtering of In-Sn alloy metal target without substrate heater and post-deposition thermal treatment. The dependency of rf-bias voltage and substrate power during deposition processing was investigated to control the electrical and optical properties of ITO films. The range of rf bias voltage is from 0 to -80 V and the substrate power is applied from 10 to 50 W. The minimum resistivity of ITO film is 5.4${\times}$10$^{-4}$ $\Omega$cm at 50 W power and rf-bias voltage of -20 V. The best transmittance of ITO films at 550 nm wavelength is 91 % in the substrate power of 30 W and rf-bias voltage of -80 V.

• Natural Product Sciences
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• v.13 no.1
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• pp.6-10
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• 2007

The ethanolic (50% v/v) extracts of Carissa carandas (fruits) (Apocynaceae) and Microstylis wallichii (tubers) (Orchidaceae) were examined for anti-inflammatory and analgesic activities in experimental animals. Carissa carandas and Microstylis wallichii (50-200 mg/kg) caused a dose dependent inhibition of swelling caused by carrageenin significantly in cotton pellet induced granuloma in rats (P < 0.05 to P < 0.001). There was a significant increase in the analgesy meter induced pain in rats. The extracts of Carissa carandas and Microstylis wallichii resulted in an inhibition of stretching episodes and percentage protection was 16.05-17.58%respectively in acetic acid induced writhing.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.473-473
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• 2000

This paper presents the 2-bit parallel algorithmic ADC using current mode for parallel method algorithm. It is operated by parallel conversion, 2-bit at each moment, and increase bit numbers by serial connection. The circuit operates in current mode. The comparison ratio can be controlled while working under mode operation. The circuit design used 0.8 ${\mu}{\textrm}{m}$ CMOS technology which capable to convert 2-bit in 50 ns, power consumed 0.786 nW, with input current 0-50 mA from 3V single supply. From simulation testing, the conversion rate is much faster than other method.

• Natural Product Sciences
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• v.9 no.3
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• pp.195-199
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• 2003

The ethanolic (50% v/v) extracts of Peristrophe bicalyculata Nees. (Acanthaceae) were examined for anti-inflammatory and analgesic activities in experimental animals. P. bicalyculata in doses of 50, 100 and 200 mg/kg caused a dose dependent inhibition of swelling caused by carrageenin equivalent to 12.25-24.49% protection and 16.62-39.44% in cotton pellet induced granuloma in rats. There was a significant increase in the tail-flick reaction time in mice (18.05-76.43% protection) and analgesy-meter induced pain in rats (14.49-56.85%) protection). The extract of P. bicalyculata resulted in an inhibition of stretching episodes and the protection range of 14.49-56.85% respectively in acetic acid induced writhing.

• Journal of the Korea Safety Management & Science
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• v.4 no.2
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• pp.199-207
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• 2002

The polycrystalline CdS of large scale were grown by chemical pyrolysis deposition for $Cu_2$S/CdS heterojunction solar cells. For high quality CdS polycrystalline thin films, the chemical solution was deposited on indium tin oxide(ITO) glasses at the temperature of 50$0^{\circ}C$ for 15 second and annealed at 35$0^{\circ}C$ for 20 minute or 50$0^{\circ}C$ for 30 second. To fabricate high efficiency solar cells, optical and electrical properties, morphology by SEM and x-ray diffraction on polycrystalline CdS thin films were investigated. From the I-V characteristics of $Cu_2$S/CdS heterojunction, the open circuit voltage, $V_{oc}$ was 0.7 V and the short circuit current, $I_{sc}$ was 4.2 mA. We found that the fill factor(FF) was 0.5 and the efficiency was 2.5%.

• YAKHAK HOEJI
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• v.43 no.6
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• pp.802-808
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• 1999

Vibrio vulnificus cytolysin has been incriminated as one of the important virulence determinants in V. vulnificus infection. In the present study, the effects of Vibrio vulnificus cytolysin on platelets were examined. Vibrio vulnificus cytolysin induced platelet aggregation and increased intracellular calcium concentration ($[Ca^{2+}]_i$) of rat platelets. These effects were abolished in $Ca^{2+}-free$ buffer (2 mM EGTA). Cytolysin also potentiated ADP-and collagen-induced platelet aggregation. Lanthanum (2 mM) inhibited cytolysin-diduced platelet aggregation. However, another $Ca^{2+}$ channel blockers, verapamil ($20{\;}{\mu}M$) or mefenamic acid ($20{\;}{\mu}M$) did not block cytolysin-induced platelet aggregation. Osmotic protectants, sucrose (50 mM) and raffinose (50 nM) suppressed platelet aggregation by 35.9% and 63.4%, respectively. V. vulnificus cytolysin increased membrane conductances of platelet membranes. These results suggest that cytolysin-induced platelet aggregation is mediated via lanthanum sensitive-calcium influx which resulted from the pore formation by V. vulnificus cytolysin.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.53 no.4
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• pp.208-212
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• 2004

In this paper, the characteristics of co-sputtered Ru-Zr metal alloy as gate electrode of MOS capacitors have been investigated. The atomic compositions of alloy were varied by using the combinations of relative sputtering power of Ru and .Zr. C-V and I-Vcharacteristics of MOS capacitors were measured to find the effective oxide thickness and work function. The alloy made of about 50% of Ru and 50% of Zr exhibited an adequate work function for nMOS. C-V and I-V measurements after 600 and $700^{\circ}C$ rapid thermal annealing were performed to prove the thermal and chemical stability of the Ru-Zr alloy film. Negligible changes in the accumulated capacitance and work function before and after annealing were observed. Sheet resistance of Ru-Zr alloy was lower than that of poly-silicon. It can be concluded that the Ru-Zr alloy can be a possible substitute for the poly-silicon used as a gate of nMOS.

• Progress in Medical Physics
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• v.19 no.1
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• pp.73-79
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• 2008

Retinal prosthesis is regarded as the most feasible method for the blind caused by retinal diseases such as retinitis pigmentosa (RP) or age related macular degeneration (AMD). Recently Korean consortium launched for developing retinal prosthesis. One of the prerequisites for the success of retinal prosthesis is the optimization of the electrical stimuli applied through the prosthesis. Since electrical characteristics of degenerate retina are expected to differ from those of normal retina, we performed voltage stimulation experiment both in normal and degenerate retina to provide a guideline for the optimization of electrical stimulation for the upcoming prosthesis. After isolation of retina, retinal patch was attached with the ganglion cell side facing the surface of microelectrode arrays (MEA). $8{\times}8$ grid layout MEA (electrode diameter: $30{\mu}m$, electrode spacing: $200{\mu}m$, and impedance: $50k{\Omega}$ at 1 kHz) was used to record in-vitro retinal ganglion cell activity. Mono-polar electrical stimulation was applied through one of the 60 MEA channel, and the remaining channels were used for recording. The electrical stimulus was a constant voltage, charge-balanced biphasic, anodic-first square wave pulse without interphase delay, and 50 trains of pulse was applied with a period of 2 sec. Different electrical stimuli were applied. First, pulse amplitude was varied (voltage: $0.5{\sim}3.0V$). Second, pulse duration was varied $(100{\sim}1,200{\mu}s)$. Evoked responses were analyzed by PSTH from averaged data with 50 trials. Charge density was calculated with Ohm's and Coulomb's law. In normal retina, by varying the pulse amplitude from 0.5 to 3V with fixed duration of $500{\mu}s$, the threshold level for reliable ganglion cell response was found at 1.5V. The calculated threshold of charge density was $2.123mC/cm^2$. By varying the pulse duration from 100 to $1,200{\mu}s$ with fixed amplitude of 2V, the threshold level was found at $300{\mu}s$. The calculated threhold of charge density was $1.698mC/cm^2$. Even after the block of ON-pathway with L-(1)-2-amino-4-phosphonobutyric acid (APB), electrical stimulus evoked ganglion cell activities. In this APB-induced degenerate retina, by varying the pulse duration from 100 to $1200{\mu}s$ with fixed voltage of 2 V, the threshold level was found at $300{\mu}s$, which is the same with normal retina. More experiment with APB-induced degenerate retina is needed to make a clear comparison of threshold of charge density between normal and degenerate retina.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.7
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• pp.854-859
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• 2018

This paper describes the characteristics of a hybrid supercapacitor module for power quality stabilization. Hybrid supercapacitor is an promising energy storage device that positioned between conventional EDLC and Li-ion battery. A cylindrical 7500F hybrid supercapacitor ($60{\times}138mm$) was assembled by using the $Li_4Ti_5O_{12}$ electrode as an anode and activated carbon as a cathode. Considering the ESR and efficiency has been designed to module with 41.6F 480V design results in 180 series combination. In order to determine the characteristics of the hybrid supercapacitor module for power system, hybrid supercapacitor cells were connected in series with active balancing circuit. As a result of measuring the 50kw UPS, it was discharged at the current of 104A~143A during the discharge in the voltage range of 350V~480V, and the compensation time at discharge was measured to be about 30s. These results can be used to stabilization of power quality by applying hybrid supercapacitor module.