• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1997.03a
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• pp.207-212
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• 1997

In estimating the formability of sheet metal, the stereo vision system contributes the accuracy of strain of sheet metal, the convenience in measuring the strain of sheet metal, and the handiness in preparing the forming limit diagram by calculating the 3D values and strain of sheet metal. The algorithm has been developed so that the 3D-coordinate values of sheet metal could be calculated by image processing which is composed of camera calibration, and the stereo matching of images in two viewpoints. By comparing with experiments, the possibility and the convenience of algorithm has been verified, which could calculate the 3D-coordinate values of sheet metal automatically by using the preprocessing of the original image of sheet metal, which had the noise before adjusting the camera calibration and the stereo matching algorithm.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.379-381
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• 2003

Metal sorption onto the ICS (Iron oxide coated sand) was studied in batch experiments. Heavy metal cations such as Cd, Pb, and Cu, and a metal anion, As, which sporadically exist in mine sites, were tested for the sorptive removal by ICS. In low pH conditions As showed the highest removal efficiency compared to the other metal cations. And the sorption removal of As was apparently pH-independent reaction. However, removal of metal cations increased with pH and above pH 7 most metal cations showed very low soluble concentrations after treatment. Such a high removal ratio of metal cations above the neutral pH appeared predominantly due to precipitation.

• Carbon letters
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• v.14 no.3
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• pp.171-174
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• 2013

The high quality contact between graphene and the metal electrode is a crucial factor in achieving the high performance of graphene transistors. However, there is not sufficient research about contact resistance reduction methods to improve the junction of metal-graphene. In this paper, we propose a new method to decrease the contact resistance between graphene and metal using directly grown graphene over a metal surface. The study found that the grown graphene over copper, as an intermediate layer between the copper and the transferred graphene, reduces contact resistance, and that the adhesion strength between graphene and metal becomes stronger. The results confirmed the contact resistance of the metal-graphene of the proposed structure is nearly half that of the conventional contact structure.

• Journal of Environmental Science International
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• v.4 no.5
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• pp.141-141
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• 1995

The waste biomass of Sacchromyces uvarum, used in fermentation industries to produce ethanol, were studied for their ability to absorb various heavy metal ions. Heavy metal ions studied in this research were Cd, Co, Cr, Cu, Ni and Pb. The order of the sorption capacity was Pb>Cu>Co=Cr=Cd>Ni. The living Sacchromyces uvarum exhibited higher metal-uptake capacity than the dead Sacchromyces uvarum. After we compare the uptake capacity of the Sacchromyces uvarum for individual metal ions with for a mixture of them, the following was observed: in the mixed heavy metal solution the uptake capacity was decreased than the one heavy metal solution. The selective uptake was observed when all . the heavy metal ions were dissolved in a mixed solution. The adsorption isotherm modelling was decribed with the Langmuir and Freundlich model. The results were in good agreement with the Langmuir model.

• Journal of Environmental Science International
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• v.4 no.5
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• pp.527-534
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• 1995

The waste biomass of Sacchromyces uvarum, used in fermentation industries to produce ethanol, were studied for their ability to absorb various heavy metal ions. Heavy metal ions studied in this research were Cd, Co, Cr, Cu, Ni and Pb. The order of the sorption capacity was Pb>Cu>Co=Cr=Cd>Ni. The living Sacchromyces uvarum exhibited higher metal-uptake capacity than the dead Sacchromyces uvarum. After we compare the uptake capacity of the Sacchromyces uvarum for individual metal ions with for a mixture of them, the following was observed: in the mixed heavy metal solution the uptake capacity was decreased than the one heavy metal solution. The selective uptake was observed when all . the heavy metal ions were dissolved in a mixed solution. The adsorption isotherm modelling was decribed with the Langmuir and Freundlich model. The results were in good agreement with the Langmuir model.

• The Microorganisms and Industry
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• v.19 no.4
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• pp.2-13
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• 1993

Some microorganisms, including actinomycetes, cyanobacteria, and other bacteria, algae, fungi, and yeast, can accumulate and retain relatively high quantities of heavy metals and radionuclides from their external environments (1-4). Both living and dead cells can be used for biosorptive metal/radionuclide removal from solution. Thus microorganisms and products excreted by or derived from microbial cells (2) may provide an alternative or adjunct to conventional techniuqes of metal removal and recovery. Recent approaches have separated the microbial growth and metal removal process to manipulate production of metal-adsorptive capacity of bacteria and metal removal process. If pre-grown cells are immobilized and used for metal removal, mathematical modeling can be applied to predict immobilized cell reactor behavior under specific process conditions. Waste and microbial adsorbent could be separated from the treated flow in one step. Once treated, the metal waste is concentrated in a small volume of sorbed form for easy metal disposal or recovery.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.105-106
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• 2017

The metal spray method, one of the surface anti-corrosion methods to prevent the corrosion of the steel material, does little effects on the material, while it can be used on a wider surface. However, metal spraying is used only in a limited environment, and research on the case of using with concrete is lacking. The purpose of this study was to observe the corrosion behavior of steels with metal spray coatings in concrete using electrochemical methods And to evaluate the performance of the method according to the type of metal used in the metal spray. As a result, the Al metal spray coating showed the best performance, because Aluminum is oxidized in the cement mortar and forms alumina oxide film.

• Laser Solutions
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• v.7 no.1
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• pp.37-47
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• 2004

Laser-assisted selective infiltration is a new method of building metal layers to make metal parts layer by layer, in which superheated microscopic metal droplets are infiltrated into a laser-preheated layer of microscopic metal powders. In this work, the selective infiltration of a low melting-point metal, Sn-37Pb wt%, was conducted to investigate the effects of such dominant parameters as superheating temperature, Nd:YAG laser power for preheating, substrate temperature, etc. The optimal conditions for successful selective infiltration of a single layer of microscopic metal powder were experimentally obtained

• Korean Journal of Computational Design and Engineering
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• v.8 no.3
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• pp.150-156
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• 2003

Direct Metal Deposition (DMD) is a new additive process producing three-dimensional metal components or tools directly from CAD data, which aims to take mold making and metalworking in an entirely new direction. It is the blending of five common technologies: lasers, CAD, CAM, sensors and materials. In the resulting process, alternatively called laser cladding, an industrial laser is used to locally heat a spot on a tool-steel work piece or platform, forming a molten pool of metal. A small stream of powdered tool-steel metal is then injected into the metal pool to increase the size of the molten pool. By moving the laser beam back and forth, under CNC control, and tracing out a pattern determined by a computerized CAD design, the solid metal part is eventually built line-by-line, one layer at a time. DMD produces improved material properties in less time and at a lower cost than is possible with traditional fabrication technologies.

• Journal of Welding and Joining
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• v.18 no.6
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• pp.62-67
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• 2000

Metallurgical characteristics of bonded region and high temperature mechanical properties of heat resistant alloy, Fe-35Ni-26Cr during liquid phase diffusion bonding were investigated employing AM17 insert metal. The insert metal for bonding, AM17 was newly developed Ni-base metal using interpolation method. Bonding of specimens were carried out at 1,403~1,463K for 600s in vacuum. The microconstituents in the bonded interlayer disappeared in the bonding temperature over 1,423K. The microstructures, alloying elements and hardness distribution in the base metal. The tensile strength and elongation of the joints at elevated temperatures were the same level as one of the base metal in the bonding temperature over 1,423K. The creep rupture strength and rupture lives of joints were almost identical to those of base metal.