• Transactions of the Korean Society of Machine Tool Engineers
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• v.15 no.1
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• pp.49-55
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• 2006

The effect of coating temperature with regard to surface properties of TiN-coated layer on hard metal(WC-Co) are experimentally investigated. Hardness, surface roughness, TiN coating thickness and adsorption force were measured in order to evaluate the effect of coating temperature. The two-way ANOVA method is used in order to evaluate the experimental data. In AIP processing, It is concluded that the furnace temperature in the range of $400^{\circ}C\~500^{\circ}C$ affected to a little increasing the number of production with the coating temperature.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.1
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• pp.61-68
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• 2003

This study deals with the use of the conjugate gradient method for the simultaneous estimation of two unknown boundary heat fluxes on the slab in reheating furnace. Temperature measurements by the experiment are used in the inverse analysis. The heat flux estimations for three different cases of measurement locations in the slab are performed: non-skid, skid, and shift-skid zones. The estimated heat fluxes for three cases indicated the three regions having local peak values of heat fluxes. The estimated temperatures at measurement locations were in good agreements with the measured temperatures within 5% relative error.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.2
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• pp.60-66
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• 2004

Increased 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 legislations, require very careful combustion management. The flame diagnostics system has been developed specially to meet these requirements. 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.

• Journal of the Korean Ceramic Society
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• v.33 no.4
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• pp.418-424
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• 1996

(Ti.W)C complex carbide was synthesized by self-propagating high temperature synthesis (SHS) chemical furnace. Attempt to find the optimal condition for synthesis of (Ti.W)C the effects of molar ratio of Ti:W:C on the synthesized powders and mechanical properties were investigated, Optimum molar ratio of these synthe-sized powder was Ti:W:C=0.7:0.2:1.0 The bulk density M,O.R Hardness Fracture toughness of (Ti.W)C complex carbide sintered at 200$0^{\circ}C$ for 60 min by hot-pressing under the pressure of 20 MPa were 7.6g/cm3, 475 MPa, 17,.7 GPa respectively.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10c
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• pp.60-65
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• 1998

This experimental Study presents the strength properties of mortar Using the Blast-furnace Slag Sand. It gives following result. The 3-days and 7-days compression strength is increase as substitution rate is higher. As W/C ratio increase, the strength is decrease. The flexural strength is increase as substitution rate is higher specially. As flexural strength ratio for compression strength is each 16.7%, 21.1%, 25.4% on 3-days, 7-days, 28-days, long age flexural strength is higher than short age.

• Proceedings of the Korea Concrete Institute Conference
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• 1995.04a
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• pp.72-77
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• 1995

Blast-furnace slag cement has been used widely as a structural material due to the latent hydraulicity of granulated ground blast furnace slag(GGBS)for a long time as The wall as ordinary portland cement. In this study, based on the fundamental investigation on the high strength and high durable concrete using the high fineness GGBS the following remarks can be made. 1) The average desired strenth of concrete is Or=600~800kg/$\textrm{cm}^2$. 2) The above high strength concrete using the high fineness GGBS is more workable than those using only OPC. 3) The adiabatic temperature and drying shringkage decrease, so the density and resistance to sea water attack increase as results. 4)The unit cement content and unit air entrained admixture at the same desired strength of concrete decrease, so the economical high strength concrete can be manufactured from using the high fineness GGBS.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.629-632
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• 1995

The formability of an automobile body panel is very important. So, we performed an annealing condition change for the development of annealing condition with temperature, atmospheric gas and the annealing cycle. Formability was changed under the influenced of the mechanical properties of steel sheet for the automobile body panel. Therefore, ot os important in the BAF(Batch annealing furnace) annealing process. Because mechanical properties were decided on the heat treatment method of the coil. So, we tested the development of mechanical properties according to the heat treatment method at the annealing furnace using the Ax atmospheric gas and the HNx atmospheric gas. As a result of several investigations, we confirmed the following characteristics ; mechanical properties change under the influence of the annealing cycle and atmospheric gas.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.717-720
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• 2007

The 3 ton/day-scale pilot plant consists of compressor, feed channel, fixed bed type gasification & melting furnace, quench scrubber, demister, flare stack and gas engine. Syngas composition of gasification using the 35.50(waste I), 4.34%(wasteII) moisture-containing solid waste showed waste I CO 25-35%, 20-40% hydrogen, waste II 25-35%, 20-30% hydrogen. Gasification melting furnace was operated $1,500{\sim}1,600^{\cdot}C$. Gas engine was generated $35{\sim}40$ kW as waste gasification syngas.

• 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.

• Journal of the Korean Professional Engineers Association
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• v.33 no.4
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• pp.77-83
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• 2000

In this study, engineering characteristics of permeable mortar using water-quenched blast furnace slag as fine aggregates were analyzed by laboratory experiments to examine its suitability for permeable concrete pavement techniques. Engineering characteristics of mortar were investigated by performing both the compressive, flexural strength tests together with the constant head permeability tests for twenty-six types of mixing samples having different percetage of slag, cement and water. After 28days of curing, every performance was tested to find optimum mixture. When the go coefficient of permeability was 10$\^$-2/cm / sec and flexural strength was 30kg/㎠, we conclusion that the best mix design in permeable mortar was made in the condition,60% of cement and 20% of water percentage of unit slag contents. From the present investigations, it is concluded that suitability for permeable concrete pavement techniques using water-quenched blast furnace slag as fine aggregates may possibly be used to achieve effects on strength together with drainage effects.