• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.502-506
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• 2000

In this study, an experimental method measuring the scroll under the temperature distribution similar to the operating condition is proposed and the results are presented. Direct measurement of the actual thermal stress is very difficult because of the rapid and complex motion of the orbiting scroll. Therefore, the experimental condition is provided on the stationary scroll heated in the electric furnace and, then, the mechanical stress and the effects of refrigerant are excluded from the resulting measurement. The experimental results are compared with these of FEM, both showing good agreement.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.370-374
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• 2001

The degree of iron recovery from dust agglomerates was investigated experimentally to determine the optimum mixing ratio of coke in cold bonded pellet(CBP) which is fed into electric arc furnace(EAE) in the minimill plant. From the XRD analysis for EAF dust, magnetite(Fe$_3$O$_4$) and franklinite(ZnFe$_2$O$_4$) was identified as major components. Maximum iron recovery was obtained for the solid carbon content of approximately 18 weight percent. From plant trials of CBP composed of this optimal mixing condition, it was observed that electric power consumption and sulfur content increased with increasing the quantity of CBP.

• Proceedings of the KSME Conference
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• 2000.04b
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• pp.931-936
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• 2000

An experimental study has been carried out of the combustion behavior of single fuel droplets of water-in-light oil emulsions in an electric furnace to elucidate the dominant factor for the occurrence of micro-explosions. The tests were carried out by changing the following four parameters; the size of water droplets in the emulsified fuels having the same water content, the ratio of water to light oil, ambient temperature in electric furnace, and the kind of fuel having different viscosity(Kerosene, Olive Oil). The result shows that the each parameter plays the different role in the effect on behavior of vaporization, explosion, ignition and combustion for single droplets of water-in-oil Emulsified fuels.

• Journal of the Korean Society of Combustion
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• v.5 no.1
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• pp.81-89
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• 2000

An experimental study has been carried on single fuel droplets of water-in-light oil emulsions in an electric furnace to elucidate the dominant factor for the occurrence of micro-explosions. The tests were carried out by changing the following four parameters; the surfactant, the ratio of water to light oil, ambient temperature in electric furnace, and four kinds of fuels having different viscosity(light-oil, kerosene, iso-octane, bunker fuel). The result shows that micro-explosion phenomena is dominated without surfactant and below 30% of water content. Explosion-time is affected by ambient temperature and viscosity of used fuel.

• Elastomers and Composites
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• v.53 no.2
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• pp.75-79
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• 2018

ZnS:Mn-glycine (ZnS:Mn-Gly) nanocomposites were synthesized by capping ZnS:Mn nanocomposites with glycine. Zinc sulfate heptahydrate ($ZnSO_4{\cdot}7H_2O$), glycine ($C_2H_5NO_2$), manganese sulfate monohydrate ($MnSO_4{\cdot}H_2O$), and sodium sulfide ($Na_2S$) were used as the source reagents. $ZnS:Mn-Gly-C_{60}$ nanocomposites were obtained by heating the ZnS:Mn-Gly nanocomposites and fullerene ($C_{60}$) at a 2:1 mass ratio in an electric furnace at $700^{\circ}C$ for 2 h. X-ray diffraction (XRD) was used to characterize the crystal structure of the synthesized nanocomposites. The photocatalytic activity of the $ZnS:Mn-Gly-C_{60}$ nanocomposites was evaluated, via the degradation of brilliant green (BG) dye under 254 nm irradiation, with a UV-vis spectrophotometer.

• Journal of the Korea Concrete Institute
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• v.11 no.3
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• pp.101-111
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• 1999

Compared with the BF slag, the EAF slag has expansion due to the reaction with water and free CaO. Therefore it is specified in Concrete Specification that the FAP slag aggregated must not be used in concrete. Because of this reason it is unusual to use the EAF slag aggregate in concrete. The EAF slag aggregate treated with accelerated and water aging was comparatively satisfied with fundamental properties, which are specific gravity, unit weight, abrasion and immersion expansion ratio, as concrete aggregate. Therefore when we measured the compressive strength till 28 days, we found that the mortar and concrete replacing the natural aggregate with the EAF slag aggregate by 4 steps had better results than the concrete using the natural aggregate in a view of the compressive strength. But at 91 days, concrete using the EAF slag aggregate had no difference with it using the natural aggregate.

• Journal of Power Electronics
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• v.6 no.3
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• pp.195-204
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• 2006

This paper presents a new compensating system, consisting of series and shunt active filters, for mitigating voltage and current disturbances. The shunt filter is used to compensate for unbalanced and distorted load currents. The series filter comprises two inverters, used to suppress voltage disturbances and handle source currents independently. This configuration is devised to reduce the overall cost of active compensators by using low-frequency high-current switches for the latter inverter. The filters are controlled separately using a novel control strategy. Since voltages at the point of common coupling contain interharmonics, conventional methods cannot be used for extracting voltage references. Therefore, voltage references are obtained from generated sinusoidal waveforms by a phase-locked loop. Current references are detected based on rotating frame vector mapping. Simulation results are presented to verify the system.

• Proceedings of the KIEE Conference
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• summer
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• pp.82-84
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• 2004

This paper has calculated DSM's latent capacity through a survey investigating electric arc furnaces in over 2,000 toe companies and related organizations. The latent capacity of DSM calculated with the same time load factor is considered in this paper. The time load factor depends on the probability of each electric arc furnace of the value to work and the consideration of experts and technician's experience. Also, this paper verifies the reliability and application of unposed capacity which compared the old latent capacity of Load Management with KEMCO and KEPCO's Direct Load Control gathering capacity.

• Journal of Ceramic Processing Research
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• v.20 no.4
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• pp.363-371
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• 2019

In this study, physical properties of normal concrete, magnetite concrete, EAF concrete, and EAF concrete with added iron powder were evaluated and a feasibility of radiation shielding is also evaluated through irradiation tests against X-rays and gamma-rays. While the unit weight of EAF concrete (3.21 t/㎥) appeared lower than that of magnetite concrete (3.50 t/㎥), the results in compressive strength of EAF concrete were greater than those in magnetite and normal concrete. While the radiation transmission rate of normal concrete reaches 26.0% in the X-ray irradiation test, only 6.0% and 9.0% of transmission rate were observed in magnetite concrete and linear relationship with unit volume weight and radiation shielding. In the gamma-ray irradiation test, the performance of EAF and magnetite concretes appeared to be similar. Through the results on the excellent physical properties and radiation shielding performance a potential applicability of EAF concrete to radiation shielding was verified.

• Magazine of RCR
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• v.10 no.1
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• pp.33-38
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• 2015