• Journal of Welding and Joining
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• v.18 no.6
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• pp.68-73
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• 2000

In case of overalyered wrapping roll, beadmark shape appear at wrapping roll surface due to irregular wear between weld bead. Irregular wear of this is caused by difference of hardness between weld bead. This study aims at investigating which matrix is good for removing of beadmark at wrapping roll surface. So, we make specimen with martensitic matrix and austenitic matrix. The overlayered alloys were deposited 4 times on a SS41 steel plate using self-shielding flux cored arc welding method. Difference of hardness between weld bead of specimen with matrix of martensite was higher than specimen with matrix of austenite both as-welded and after heat treatment. Therefore, austenitic matrix is between than martensitic matrix for removing of beadmark of wrapping roll surface.

• Journal of Welding and Joining
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• v.31 no.4
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• pp.62-66
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• 2013

Overlay welding is carried out to improve the corrosion resistance, wear resistance and heat resistance on the surface of the chemical plant and steelmaking plant structures. In overlay welding, control of the bead size and the temperature distribution of weldment are particularly important because that is directly connected to the improvement of quality and productivity. The aim of this study is to model the welding heat source that is very useful to analyze the bead size and temperature distribution of weldment. To find the welding heat source model, numerical analyses are performed by using FE software MSC-marc.

• Journal of Welding and Joining
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• v.31 no.4
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• pp.67-72
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• 2013

Overlay welding is carried out to improve the corrosion resistance, wear resistance and heat resistance on the surface of the chemical plant and steelmaking plant structures. In overlay welding, control of the bead size and the temperature distribution of weldment are particularly important because that is directly connected to the improvement of quality and productivity. The aim of this study is to model the welding heat source that is very useful to analyze the bead size and temperature distribution of weldment. To find the welding heat source model, numerical analyses are performed by using FE software MSC-marc.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.7
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• pp.700-705
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• 2009

In order to enhance the dynamic stiffness of automotive panel, effect of bead and curved surface was investigated. Modal test was performed for principle specimens which have various kinds of beads, holes and curved surfaces. Test was also performed for conventional dash panel assembly and rear floor panel assembly and curved shaped ones. Results showed that curved shape increased the natural frequency of automotive panel more effectively than the bead. Finite element analysis was also performed and yielded good match with the test results.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1999.05a
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• pp.111-116
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• 1999

Over the last few years, there has been a growing interest in quantitative representation of heat transfer and fluid flow phenomena in weld pools in order to relate the processing conditions to the quality of the weldment produced and to use this information for the optimization and robotization of the welding process. Normally, a theoretical model offers a powerful alternative to estimate the important input parameters and to calculate the effects of varying any of parameters. To solve this problem, a transient 2D(two-dimensional) heat conduction and a transient 2D axisymmetric heat and fluid model were developed for determining weld bead geometry and temperature distribution for the GMA(Gas Metal Arc) welding process. The equation was solved using a general thermofluid-mechanics computer program, PHOENICS code, which is based on the SIMPLE algorithm. The simulation results showed that the calculated bead geometry from two developed models reasonably agree with the experiment result.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.10a
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• pp.170-173
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• 2002

The object of this study is to investigate the effect of compounded welding through the AE (Acoustic Emission) characteristics on static tensile test. This study was carried out a SM 490A, high tension steel using the low hydrogen type E4316 of electronic shield metal arc welding and compound wire of $CO_2$gas arc welding. $CO_2$welding, weak in the intensity of HAZ (Heat Affected Zone), can be improved by being combined with coated arc welding, Coated arc welding, weak in the intensity of the bead, can be improved by being combined with $CO_2$welding. Especially, electronic coated arc welding and $CO_2$welding complement the mechanical intensity of HAZ and the bead with each other. So, compounded welding increases the intensity in the special parts and enhances the quality of goods.

• KSBB Journal
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• v.8 no.3
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• pp.266-271
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• 1993

The effective diffusion coefficients of glucose, sucrose and fructo-oligosaccharides in Ca-alginate gel beads at high concentration of sucrose solutions were investigated at $50^{\circ}C$. A mathematical model for the kinetics of fructo-oligosaccharide production using immobilized cells was proposed and compared with experimental results varying the bead size, the substrate concentration and the bead ratio. Very low values of diffusion coefficients ranging $1.2-7.6\times10^{-7}\textrm{cm}^2$/sec were obtained, and the predicted results were in good agreement with experimental ones in all cases tested.

• Biomolecules & Therapeutics
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• v.7 no.1
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• pp.97-104
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• 1999

A new antibiotic bead, CJ-40003 is a combination of three antibiotics, tobramycin, vancomycin and cefazolin embedded in bone cement, for the treatment of osteomyelitis. To evaluate the general pharmacological properties of CJ-40003, the effects of its active ingredients were investigated in mice, rats, dogs and isolated guinea pig ileum. The combination of three antibiotics (CA) did not affect general behavior, central nervous system, smooth muscles, gastrointestinal system, cardiovascular and respiratory system and water and electrolytes excretion when administered intravenously at the doses of 0.3, 1 and 3 mg/kg, respectively, into experimental animals. The CA had no effect on the contractile response of the isolated guinea pig ileum to various spasmogen at concentrations of 1, 3 and 10 $\mu\textrm{g}$/ml, respectively. In conclusion, the active ingredients of CJ-40003 showed no pharmacological effect in these studies.

• Journal of the Korean Society for Precision Engineering
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• v.11 no.4
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• pp.165-173
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• 1994

Retroreflector is different from other reflecting surfaces as it mades reflection in which radiation is returned in directions close to its incoming direction. Because of this characteristics, retroreflectors find many applications in traffic safety related areas. Retroreflectors are usually made using comer cubes, or partially coated glass beads. These glass beads can be made very small, so that they can be coated on sheets or mixed with paints. The design of glass type retroreflector depends on glass bead's shape and material, and its optical characteristics are related to the refractive index of glass. In this paper, a method of anlyzing glass bead type retroreflector's sptical characteristics with respect to shape and optica property of the glass, is presented. First, the coefficient of retroreflection, which is a measure of retroreflector's optical characteristics, is derived analytically using geometrical optics method. And the result is plotted using numerical methods. The results show good match with those obtained experimentally, which were supplied from a commercial retroreflector manufacturer.

• Bulletin of the Korean Chemical Society
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• v.22 no.8
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• pp.867-871
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• 2001

We have studied the characteristic wave propagation in 1,4-CHD-Bromate-Ferroin reaction system and we have examined the bead size effect on the wave propagation of the system by adopting a half-divided Petri dish which is separated into two parts by the size of cation-exchange resin. It has been done to understand the reaction process inducing the characteristic wave behavior in the system. The characteristic wave behavior of the system is in the spontaneous induction of a revival wave with a long time lag. We have obtained a result that the revival wave is not affected by the size of catalyst-doped beads while the initially induced wave is influenced by the size of beads. It means that the two waves are induced by different reaction processes each other and the revival wave is induced by an uncatalyzed reaction process.