• The Transactions of the Korean Institute of Power Electronics
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• v.9 no.1
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• pp.81-87
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• 2004

This paper describes a design method of electromagnetic interference (EMI) filter for pulse-width modulation (PWM) inverter-fed AC drives used for home appliances such as washing machine and air conditioner. The generating and coupling mechanisms of the conducted EMI for AC drives are first investigated. The design procedure of the EMI filter based on the EMI separation principle is then presented. Experiments we carried out for the PWM inverter-fed induction motor drive system and it is shown that the results satisfy the EN55014 EMI regulation.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.391-394
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• 1999

Until now, there is no report for the relationship between the condition of addressing and the characteristics of surface discharge in ac-PDP. We have known that such these experiment was important to drive ac PDP Therefore, this paper deals with the probability of transfer and the character of luminance according to addressing voltage(Va) and blocking voltage(Vg) in addressing period and sustain voltage in sustaining period and we use waveform according to ADS(Address and Display period Separation) method

• 대한정형외과스포츠의학회:학술대회논문집
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• 2004.09a
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• pp.36-36
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• 2004

• Applied Chemistry for Engineering
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• v.33 no.5
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• pp.488-495
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• 2022

Activated carbon (AC) and carbon molecular sieve (CMS) have attracted attention as porous materials for recovery and separation of greenhouse gases. The carbon molecular sieve having uniform pores is used for collecting and separating gases because it may selectively adsorb a specific gas. The size and uniformity of pores determine the performance of the CMS, and chemical vapor deposition (CVD) is widely used to coat the surface with a predetermined thickness in order to control the CMS's micropores. This CVD method can be used to control the size of pores in CMS manufacturing, but it must be optimized because of its various experimental variables. Therefore, in order to produce AC and CMS for gas adsorption and separation, this review focuses on various activation processes and pore control technologies by CVD and surface treatment.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2016-2018
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• 1999

Until now, there is no report for the relationship between the condition of addressing and the characteristics of surface discharge in ac- PDP. We have known that such experiments were important to drive a-PDP. Therefore, This paper deals with the probability of transfer and the characteristics of luminance according to addressing voltage (Va), blocking voltage (Vg)in addressing period and sustain voltage(Vs)in sustaining period and we use waveform according to ADS (Address and Display period Separation) method.

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.2156-2159
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• 2005

ADS(Address Display Period Separation) driving method has been considered to be the most appropriate driving technique for AC PDP. ADS driving method is composed of reset, address, sustain and erase period. Therefore, a long time should be allocated to an address period, which results in a reduction of brightness. To realize a high luminance and high picture quality, it is necessary to high speed addressing. However, address discharge time lag increases as the temperature decreases, which can cause the misfiring and low picture quality In this paper, the electric field effect and priming particle effect are investigated in order to reduce the address discharge time lag at low temperature. Address discharge time lag was reduced effectively when the priming particles are provided.

• 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.

• Korean Chemical Engineering Research
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• v.50 no.3
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• pp.527-534
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• 2012

The adsorption dynamics of activated carbon (AC) and carbon molecular sieve (CMS) beds were studied to recover ethylene from FCC fuel gas. In this study, the FCC fuel gas used consisted of six-component mixture ($CH_4/C_2H_4/C_2H_6/C_3H_6/N_2/H_2$,32:15:14:2:12:25 vol.%). And the breakthrough experiments of adsorption and desorption were carried out. The breakthrough sequence in the AC bed was $H_2$ < $N_2$ < $CH_4$ < $C_2H_4$ < $C_2H_6$ while the sequence in the CMS bed was $H_2$ < $CH_4$ < $N_2$ < $C_2H_6$ < $C_2H_4$. The separation performance of the CMS bed during the adsorption step was lower than that of the AC bed. However, due to the characteristics of kinetic separation, the CMS bed could remove $CH_4/N_2$ as well asthe molecules that are larger than $C_2H_6$, which was not easy to be done by the AC bed. Since it was hard to regenerate the adsorption bed by simple depressurization, vacuum regeneration should be adopted. As a result, the pressure vacuum swing adsorption (PVSA) process, consisting of CMS pretreatment process and AC main process, was suggested to recover ethylene efficiently.

• Journal of the Korean Chemical Society
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• v.15 no.2
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• pp.45-48
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• 1971

The various eluents have been used for the separations of alkaline earth metals by elutions through cation exchange resin column by many investigators. We find, the mixed solution of 1M HAc and 1M NaAc (pH 4.75) is the best eluent for this purpose, becouse the one step elution through 7cm Dowex 50w${\times}$8(100~200mesh) resin column with this eluent, gives the quantitative separation. When 2M NaAc is used as a eluent Sr(II) and Ba(II) is separated easily without any contamination of Mg(II) andCa(II). The Ca-Pb alloy which is composed of Cu, Ca, Sr, Ba and abundance of Pb metal is separated quantitatively into its components by the two step elution with 0.3M HAc + 0.3M NaAc(PH 4.75) and 0.5M HAc + 0.5M NaAc(PH 4.75) as eluents through 10cm resin column.

• Journal of the Korean Chemical Society
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• v.15 no.2
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• pp.49-54
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• 1971

It is shown that the impurities of Cu(II), Pb(II), Zn(II) and Ag(I) in Bismuth metal and the components of Pb(II), Zn(II) and Sn(IV) in Bismuth alloy are separated into their components from each other by elutions through $3.14cm^2{\times}10cm$ cation exchange resin, $Dowex\;50w\;{\times}\;8$ (100~200 mesh), column with the mixed solutions of HAc and NaAc as the eluents. The elution curve of Fe(III) has a long tailing and is not separated quantitatively from Bi(III). The eluents used for this separation are as follows; 1M HAc + 0.1M NaAc (pH 3.36) for Fe(III) and Bi (III). 0.3M HAc + 0.3M NaAc (pH 4.70) for Cu(II), Pb(II) and Zn(II). 0.5M HAc + 0.5M NaAc (pH4.70) for Ag(I) and Sn(IV). The analysis of cations eluted are carried out by spectrophotometry and EDTA titrimetry. Their recoveries are more than 99%.