• Proceedings of the Korea Concrete Institute Conference
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• 1996.10a
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• pp.148-153
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• 1996

Concrete with ground granulated blast-furnace slag can be affected by frost attack because the reaction of hydration is slow at the early age. In this study, therefore, the freezing and thawing test has been carried out to investigate the freezing and thawing resistance on concrete with ground granulated blast-furnace slag. The freezing and thawing test has been performed on concrete a blended cement, which was substituted by ground granulated blast-furnace slag with 4 kinds of ratio (non-admixture, 20%, 40% and 60%). And also tested on concrete added the AE agents to the concrete of same mix proportion to search the improvement effects about the resistance. As a result, the freezing and thawing resistance showed a tendency of reduction in proportion to the increase of the substitution ratio. For non-AE concrete, resistances of the freezing and thawing were very poor as the durability index indicated less than 5.8%. For AE concrte, resistance of the freezing and thawing were excellent as the durability index indicated more than 80.9%.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.3 no.1
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• pp.85-92
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• 1993

Large single crystals of olivine were grown by using image furnace(floating zone furnace)under controlled partial pressure of oxygen. The transparent crystals have maximum sizes 65mm in length by 7mm in diameter. When partial pressure of oxygen was decreased, the portion of secondary phases in crystals were increased so that it made crystals dark brown. The secondary phases were proved to be solid solution of Mg, Si, and Fe by electron microprobe analysis. Mg was major portion and the rest was minor.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.103-104
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• 2019

The aim of the research is assessing the possibility of recovering the compressive strength of the mortar mixture replaced excessively high volume of blast furnace slag accidently. As a result of the experiment, in the case of compressive strength, painting sodium oxide showed higher compressive strength recovery effect than painting calcium oxide. As a curing temperature, 20℃ showed advanced result rather than 65℃. From the wet curing, the reaction was confirmed, deeper penetration depth was checked at 20℃ than 60℃ temperature. Therefore for the concrete mixture with excessively high volume of blast furnace slag, it is considered that painting sodium hydroxide and curing 20℃ can recover the compressive strength effectively.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.205-206
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• 2019

This study investigated the fluidity and compressive strength properties of blast furnace slag based non-cement paste containing ferronickel slag powder to evaluate the possibility of use in for cement replacement materials. As a result, the fluidity of non-cement paste showed a higher flow as the mixing ratio of ferronickel slag powder increased. The compressive strengths similar to those of the non-cement paste using only blast furnace slag powder were obtained when 5 and 10% of ferronickel slag powder were used.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.38-39
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• 2019

Mechanical properties of concrete containing furnace slag according to the CBS Dust Replacement Ratio were analyzed. The experimental study found that the compressive strength was excellent in the early age when the CBS Dust was replaced, and the drying shrinkage was excellent, and the replacement of CBS Dust 5% on the concrete containing the furnace slag would have a positive effect.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.18 no.6
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• pp.690-696
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• 2009

This paper introduces the automatic fine Bituminous Coal injection lance position control method using flame image process. The fine Coal injection lance is used to supply additional heat into the furnace in Mill plant. It injects fine coal into high pressured air flow and produces very heated and high pressured flame. For the such high temperature and pressure, the fine coal injection lance effects not only efficiency of burner but also furnace abrasion. To keep efficient combustion status and to avoid the abrasion, in this paper, the flame is monitored by computer image process. This paper proposes the flame image process method and lance position control according to calculated result for flame image process.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.565-568
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• 2004

Properties examination of concrete using blast-furnace slag instead of cement is necessary, so it is planed that: basic data for utilization and performance management of blast-furnace slag by means of cement replacement is presented with experimental comparison and investigation of engineering properties of concrete according to the replacement ratio and fineness of blast-furnace slag.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.40 no.12
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• pp.1262-1268
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• 1991

The electric furnace which has time delay and time varying characteristics cannot be controlled easily. In this paper, a fuzzy controller for a electric furnace is implemented using one chip processor 8751 and IBM PC. The fuzzy controller is implemented in the PC. The One chip processor 8751 can sense the furnace internal temperature and pass it to IBM PC and generate the driving signal for SSR. The membership function of the fuzzy controller is determined by Least Square method. from the experiments, we can show that the fuzzy controller can improve robustness to the load variation. And the settling time is reduce 4500 (sec) to 2500 (sec).

• The Transactions of the Korean Institute of Electrical Engineers
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• v.45 no.4
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• pp.568-573
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• 1996

The amorphous silicon films deposited by low pressure chemical vapor deposition are crystallized by the various annealing techniques including low-temperature furnace annealing and two-step annealing. Two-step annealing is the combination of furnace annealing at 600 [.deg. C] for 24 h and the sequential furnace annealing at 950 [.deg. C] 1h or the excimer laser annealing. It s found that two-step annealings reduce the in-grain defects significantly without changing the grain boundary structure. The performance of the poly-Si thin film transistors (TFTs) produced by employing the tow-step annealing has been improved significantly compared with those of one-step annealing. (author). 13 refs., 6 figs., 1 tab.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2011.05a
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• pp.75-76
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• 2011

Hot-rolled steel plates of SPHC and SS400 were oxidized at 600, 750 and $900^{\circ}C$ for 2hr in air. With an increase in oxidation temperature, their oxidation rates increased, being accompanied with formation of pores and cracks in the thickened oxide scales that were non-adherent. The SPHC steels that were manufactured by either the arc furnace or the blast furnace displayed similar oxidation rates, indicating that their oxidation rates were insensitive to the manufacturing processes. The medium-carbon SS400 steel displayed a little faster oxidation rates than the low-carbon SS400 steel, indicating that the carbon content did not significantly influence the oxidation rates.