• Proceedings of the KIPE Conference
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• 1998.07a
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• pp.149-153
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• 1998

In this paper A switched mode AC/DC three phase boost converter with high power factor and sinusoidal input current waveform is analyzed and simulated. The proposed converter retain high power factor and sinusoidal input current waveform even under electric arc welder load. It is shown that experimental result and simulation waveform yield a sinusoidal input current waveform at high power factor.

• Proceedings of the KIPE Conference
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• 2007.07a
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• pp.343-346
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• 2007

Recently, many nations have released standard such as EN61000-3-2 to impose a limit on the harmonic current to prevent distortion of AC line and to save energy. Also, the limit on the harmonic current makes use of a trade barrier. Therefore, Power factor correction must have been suitable for a limit on the harmonic current. This paper presents AC servo motor drive to have merits of high power factor for Desk-Top Robot.

• Proceedings of the KIPE Conference
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• 2003.07a
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• pp.15-18
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• 2003

The electric power, regenerated while railway vehicles braking or running downhill, makes U line voltage rise and the feeding system may not be secure. In order to keep away from these kind of insecurity, the regenerative energy should be consumed by loads or transmitted to the AC side via certain devices such as DC/AC converters. This paper introduces the developed regenerative inverter for electric railway.

• Proceedings of the KIEE Conference
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• 1992.07b
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• pp.1035-1037
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• 1992

Generally, fuel cell has characteristics of low voltage, large current and voltage variation under load change. Therefore, DC output voltage of fuel cell is too low to convert into AC with high efficiency and good performance. For this reason, fuel cell generating system is composed of DC-DC converter and inverter in cascade. This paper used 2-phase boost DC-DC converter to obtain low distortion waveform and reduce input-output current ripple, and discussed inverter which can be operated in independent drive mode and utility line interface drive mode. Then, the change of modes can be achived smoothly.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.821-825
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• 2002

ZnO thick films by Sol-Gel processing were investigated electrics, optics and the sensing characteristics of CO gas. Using the znic acetate dihydrate and acetylaceton (AcAc) as a chelating agent, stable ZnO sol was synthesized. ZnO phase was crystallized through the heat-treatment at $70^{\circ}C$ for 4hrs and influenced the sensing characteristics of the electrics and CO gas by uniform particle distributions not related particle size. The samples on the alumina substrate by thick films were investigated the properties of electrics and the effect of sensing. The sensitivity was so excellent in the sample of the heat-treatment at $600^{\circ}C$ for 12hrs and good in the heat-treatment for 1hrs generally. Crystallization and volatilization of organic materials according to the change of heating treatment temperature of thick films were analyzed by TG-DTA, XRD and mirostructure of thick films were observed by SEM.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.381-383
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• 2008

One of important factors responsible for image sticking in AC PDP is a sputtering of MgO layer under ionic bombardment. Sputtered Mg particles can migrate to the neighbor cells, where the migration makes a change of discharge condition. It leads to the local non-uniformity of a luminescence in the panel, resulting in the image sticking.

• Proceedings of the KIPE Conference
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• 2016.07a
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• pp.40-41
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• 2016

The inverter resistance welder requires AC/DC converter of high efficiency because the converter changes a commercial ac power source to low voltage dc power source. Harmonic components that occur in the conversion process of converter decrease system power factor and deal great damage in electric power system. To improve such problems, this paper proposes a high efficiency AC/DC converter for inverter resistance welder. The switching devices in the proposed converter are operated by soft switching technique using a new quasi-resonant circuit. As a result, the proposed AC/DC converter obtains low switching power loss and high efficiency.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.27 no.4
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• pp.262-267
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• 2014

This study describes that light flicker of LED lamp is improved by placing an AC-powered LED block in each phase of three-phase AC power. Rectified current is considered as an instantaneous luminous flux because the current flowing through the LED block is proportional to the amount of light emitted by the LED block. Percent flicker is calculated simply by modeling the rectified current flowing through the LED block to a triangular wave current. Percent flicker is 100% in single-phase AC powered LED lamp. Percent flicker of the same level as that in an incandescent lamp (6%~14%) is however, achieved if light emission starts before $40^{\circ}$ in each voltage phase of three-phase AC power.

• Biomolecules & Therapeutics
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• v.17 no.3
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• pp.299-304
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• 2009

Rosiglitazone maleate (RGM) is widely used for improving insulin resistance. RGM is a moderate inhibitor of cytochrome P450 2C8 (CYP2C8) and is also mainly metabolized by CYP2C8. The aim of this study was to determine whether the effect of RGM on CYP2C8 is altered by co-treatment with other drugs, and whether amlodipine camsylate (AC) changes the pharmacokinetics (PK) of RGM. Of the 11 drugs that are likely to be co-administered with RGM in diabetic patients, seven drugs lowered the $IC_{50}$ value of RGM on CYP2C8 by more than 80%. In vitro CYP2C8 inhibitory assays of RGM in combination with drugs of interest showed that the $IC_{50}$ of RGM was decreased by 98.9% by AC. In a pharmacokinetic study, Sprague-Dawley (SD) rats were orally administered 1 mg/kg of RGM following by single or 10-consecutive daily administrations of 1.5 mg/kg/day of AC. No significant changes in the pharmacokinetic parameters of RGM were observed after a single administration of AC, but the AUC and $C_{max}$ values of RGM were significantly reduced by 36% and 31%, respectively, by multiple administrations of AC. In conclusion, RGM was found to be affected by AC by in vitro CYP2C8 inhibition testing, and multiple dosing of AC appreciably changed the pharmacokinetics of RGM. These findings suggest that a drug interaction exists between AC and RGM.

• Herbal Formula Science
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• v.19 no.2
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• pp.23-38
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• 2011

Objectives : Atractylodes chinensis(AC) and Phellodendron amurense Ruprecht(PAR) have been used as anti-inflammatory medicines. However, the effects of AC, PAR and Yimyosan on AP were not examined. To prove this, We decocted the dried prescription of AC and PAR with boiling distilled water and freeze-dried to be powdered. AC, PAR and Yimyosan was administrated intraperitoneally. Methods : 1h after administration, cerulein was injected hourly six times. 6hrs after last cerulein injection, mice were sacrificed, then the pancreas and blood were harvested. Serum amylase and lipase, neutrophil infiltration, pancreatic cytokines were used as the parameter of severity of AP. Results : As a result of assessment the parameters of AP, AC alone treatment did not inhibit the severity of AP, however PAR treatment inhibited the severity of AP significantly. Yimyosan also showed the protective effects against AP at lower doses, however AC alone plus PAR alone extract did not show the protective effects significantly. Conclusions : In conclusion, PAR extract has a protective effects on AP, and the effects could be increased by co-treatment with AC.