• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.365-368
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• 2002

This paper considers transference number in calculating diffusion coefficient of chloride ions of concrete and mercury intrusion porosimetry to investigate the volume and distribution of pore size, respectively, analyzing and discussing the property of resistance to chloride ion of concrete with granulated blast furnace slag. The experimental results show that the diffusion coefficient of chloride ion decreases with the rise of quantity of granulated blast furnace slag and pore structure of concrete with granulated blast furnace slag is different from that of OPC concrete. And from the results of regression analysis, the result showed that the diffusion coefficient of chloride ions is affected by capillary pore above 50nm.

• Journal of Korean Society for Atmospheric Environment
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• v.12 no.5
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• pp.577-585
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• 1996

A screening study was performed in order to resolve the flow, combustion and emission characteristics of the gas furmace with co-axial diffusion flane burner. A control-valume based finite-difference method with the power-law scheme was employed for discretization. Numerical procedure for the differential equation was used by SIMPLEST to enclosute rapid converge. A k-.varepsilon. model was incorporated for the closure of turbulence. The mass fraction and mixture fraction were calculated by cinserved scalar method. An equilibrium analysis was employed to determine the concentration of radicals in the product stream and conserbation equations were them solved for N amd NO by Zelovich reaction scheme. The method was exercised in a simple one-dimensional case first, to determine the effects of air ratio, temperature and residence time on NO formation and applied to a furnace with co-axial diffusion flame burner.

• 한국연소학회:학술대회논문집
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• 2005.10a
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• pp.43-49
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• 2005

Social interest and request about low pollution waste treatment process are growing and gasification melting method, as a new technology concept, is risen. The necessity of engineering analysis to determine design standards and operation condition is required. In this study, the objective and function of components and operation process of various gasification melting furnaces such as shaft type, fluidized bed and Rotary Kiln type gasification melting furnace are reviewed and the design standard and operation range of gasification melting furnace are determined by inspecting the change of output and operation condition with input condition change.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.499-502
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• 2003

Increase energy costs have placed demands for improved combustion efficiency, high equipment availability, low maintenance and safe operation. Simultaneously low NOx modification, installed due to stricter environmental legislation, require very careful combustion management. We aimed at gaining the relationship between burner flame image and emissions such as NOx and unburned carbon in furnace by utilizing the image processing method. For the first step of development, its possibility test was undertaken with bench furnace. The test proceeded to the second step with pilot furnace, the system was observed to be effective for evaluating the combustion conditions. By using this technology, it is possible to perform continuous monitoring of the combustion conditions and instant detection of individual changes for each burner to prevent future loss of ignition.

• Journal of Advanced Marine Engineering and Technology
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• v.28 no.8
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• pp.1251-1257
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• 2004

In order to analyze the heat transfer phenomena in the plasma flames, a mathematical model describing heat and fluid flow in an electric arc has been developed and used to predict heat transfer from the arc to the steel bath in a DC Electric Arc Furnace. The arc model takes the separate contributions to the heat transfer from each involved mechanism onto account, that is radiation, convection and energy transported by electrons. The finite volume method and a SIMPLE algorithm are used for solving the governing MHD equations, that are conservation equations of mass, momentum and energy together with the equations describing a standard k-${\varepsilon}$ model for turbulence. The model predicts heat transfer for different currents and arc lengths. Finally these calculation results can be used as a useful insight into plasma phenomena of the industrial-scale electric arc furnace. From these results, it can be concluded that higher arc current and longer arc length give high heat transfer

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.806-810
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• 2008

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 Korean Institute of Building Construction Conference
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• 2016.10a
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• pp.54-55
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• 2016

Recently in the construction industry, industrial by-product admixtures like blast-furnace slag fine particles (BS henceforth) are being used as binding material, reducing the use of cement, and measures to reduce CO₂ emissions are being examined on various levels. However, the BS being used domestically varies depending on the origin of resources, and by circulating BS that is inappropriate to the KS standard, problems are occurring in terms of changes and declines in the quality of concrete which uses it. Therefore in this study the liquid densimeter principle was used to assess various BS fineness qualities; with 100 g/L fixed, a 1,000cc mass cylinder was most appropriate for assessing the quality of cement fineness.

• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.156-158
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• 2005

The computation of design parameters and the electromagnetic analysis of 0.5 Mw- class Induction furnace with 3-dimensional modeling are Introduced by using FEM techniques, And model of flux distribution and eddy current distribution induced in induction furnace are analyzed and presented. It is more necessary that for melting industry depending on metal material field, the design technique of induction furnace is quite urgent at exchanging introduction of technology between metal material and electrical energy conversion by power electronics field.

• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.852-854
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• 2003

A aluminum recycling industry is one of new application of Linear Induction Motor(LIM). As the example a melting furnace. which is using LIM, to melt conductor which is chipped and scrapped is supposed for the aluminum recycling industry. So, in this paper, the LIM for melting furnace are designed. And a electro-magnetical characteristic of designed model is analyzed by 2D-FEM.

• Analytical Science and Technology
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• v.7 no.4
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• pp.555-561
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• 1994

A method was described for the graphite furnace atomic absorption spectrophotometric determination of trace cadmium, copper, chromium and lead in urine samples. The elements were directly determined without any other treatments. The ash temperature was intensively optimized to improve the large background by the removal of organic materials and alkali and alkali earth metals in urine samples. Two kinds of standard solutions were used to plot calibration curves. From the recovery data, it could be confirmed that the analytical results with the synthetic urine matrix similar to real urine were more accurate than with a deionized water matrix.