• Journal of the Speleological Society of Korea
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• no.82
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• pp.8-12
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• 2007

In this paper, we have investigated the characteristics of the magnetic abrasive using sludge on polishing of internal finishing of seamless stainless steel tube applying magnetic abrasive polishing. Either green carborundum(GC) grain was used to resin sludge at a low temperature, and the sludge of magnetic abrasive powder was synthesized and crushed into 200 meshes. Surface roughness was measured before and after polishing, and more than 38% of improvement of surface roughness was achieved when grain was used under a specific condition. Even though some degree of surface roughness due to deeper scratches still exist, but the result showed a prospective magnetic abrasive polishing using sludge with green carborundum grains.

• Transactions on Electrical and Electronic Materials
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• v.6 no.3
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• pp.128-132
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• 2005

In this paper, we have investigated the characteristics of the magnetic abrasive using sludge on polishing of internal finishing of seamless stainless steel (STS304) tube applying magnetic abrasive polishing. Either white alumina (WA) or green carborundum (GC) grain was used to resin sludge at a low temperature, and the sludge of magnetic abrasive powder was synthesized and crushed into 200 meshes. Surface roughness was measured before and after polishing, and more than $40\%$ of improvement of surface roughness was achieved when WA grain was used under a specific condition. Even though some degree of surface roughness due to deeper scratches still exist, but the result showed a prospective magnetic abrasive polishing using sludge with WA or GC grains.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.23 no.1
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• pp.69-74
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• 2014

An OrthoMTA compacter is made by machining a Ni-Ti alloy wire using tapered helix creep-feed grinding machines. This aim of this study is to find the optimal dressing conditions to sharpen the corner of a cubic boron nitride (CBN) wheel. On the basis of the results of various experiments, it is verified that the most important factors in dressing are the dressing depth and feeding method, whereas the feed rate has less importance for producing a smaller corner R value. The study also finds the optimum dressing depth to reduce the dressing time, a feeding speed and method to stabilize the machining, and the mesh grade for the CBN wheel to make the groove of the compacter deeper.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.77-80
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• 2004

In this paper, we have investigated the characteristics of the magnetic abrasive using sludge on polishing of internal finishing of seamless stainless steel (STS304) tube applying magnetic abrasive polishing. Either white alumina (WA) or green carborundum (GC) grain was used to resin sludge at a low temperature, and the sludge of magnetic abrasive powder was synthesized and crushed into 200 meshes. Surface roughness was measured before and after polishing, and more than 40% of improvement of surface roughness was achieved when WA grain was used under a specific condition. Even though some degree of surface roughness due to deeper scratches still exist, but the result showed a prospective magnetic abrasive polishing using sludge with WA or GC grains.

• Journal of the Speleological Society of Korea
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• no.70
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• pp.45-50
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• 2006

The magnetic polishing is the useful method to finish using magnetic power of magnet. This method is one of precision polishing techniques and has an aim of the clean technology using for the pure of gas and inside of the clean pipe for transportation. The magnetic abrasive polishing method is not so common for machine that it is not spreaded widely. There are rarely researcher in this field because of non-effectiveness of magnetic abrasive. Therefore, in this paper deals with development of the magnetic abrasive using worthless mineral. In this development, abrasive grain WA and GC used to resin bond fabricated low temperature. And magnetic material was fabricated from the worthless mineral which were closed into 200 mesh grit type. The XRD analysis result show that only WA and GC abrasive and worthless mineral crystal peaks detected which explains resin bond was not any more chemical reaction. From SEM analysis it is found that WA and GC abrasive and worthless mineral were strong bonding with each other by bond.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.6
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• pp.151-157
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• 2004

In this paper deals with behavior of the magnetic abrasive using sludge on polishing characteristics in a new internal finishing of seamless stainless steel tube applying magnetic abrasive polishing. The magnetic abrasive using sludge-abrasive grain WA and GC used to resin bond fabricated low temperature. And sludge of magnetic abrasive powder fabricated that sludge was crused into 200 mesh. The previous research have made an experiment in the static state the movement of magnetic abrasive grain is nevertheless in the dynamic state. In this paper, We could have investigated into the changes of the movement of magnetic abrasive grain. In reference to this result, we could have made the experiment which is set under the condition of the magnetic flux density, polishing velocity according to the form of magnetic brush.

• Journal of the Korean Society of Safety
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• v.19 no.2
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• pp.6-10
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• 2004

The magnetic polishing is the useful method to finish using magnetic power of magnet. This method is one of precision polishing techniques and has an aim of the clean technology using for the pure of gas and inside of the clean pipe for transportation. The magnetic abrasive polishing method is not so common for machine that it tis not spreaded widely. There are rarely researcher in this field because of non-effectiveness of magnetic abrasive. Therefore, in ths paper deals with development of the magnetic abrasive using sludge. In this development, abrasive grain WA and GC used to resin bond fabricated low temperature. And magnetic material was fabricated from the sludge which were crused into 200 mesh and average diameter ${\o}$1.2mm ball type. The XRD analysis result show that only WA and GC abrasive and sludge crystal peaks detected which explains resin bond was not any more chemical reaction. From SEM analysis it tis found that WA and GC abrasive and sludge were stron bonding with each other by bond.

• Journal of the Korean Society of Safety
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• v.23 no.5
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• pp.43-48
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• 2008

The magnetic polishing is the useful method to finish some machinery fabrications by using magnetic power. This method is one of the precision polishing techniques and has an aim for clean technology in the transportation of the pure gas in the clean pipes. The magnetic abrasive polishing method is not so common in the field of machine that it is not known to widely. There are only few researchers in this field because of non-effectiveness of magnetic abrasive. Therefore, in this paper deals with development of the magnetic abrasive using Ba-Ferrite. In this development, abrasive grain GC and CBN has been made by using the resin bond fabricated at low temperature. And magnetic abrasive powder was fabricated from the Ba-Ferrite which was crushed into 200 mesh. The XRD analysis result shows that only GC, CBN and Ba-Ferrite crystal peaks were detected, explaining that resin bond was not any more to contribute chemical reaction. From SEM analysis, we found that GC, CBN abrasive and Ba-Ferrite were strongly bonding with each other.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.73.1-73
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• 2003

In order to cultivate watermelon on farm, grafting of the watermelon seedling to the watermelon stock is necessary because the watermelon root is less viable than the root of watermelon stock. Recently, commercially important watermelon varieties further require a resistant stock against especially CGMMV to control the heavy loss of the total yield of watermelon by CGMMV infection. Therefore, we have set out a project to develop a CGNEMV-resistant watermelon stock. We have successfully transformed dozens of watermelon stocks (gongdae) during last two years especially using a cDNA encoding the coat protein of CGMMV (cucumber green mottle mosaic virus). Recently we have tested levels of resistance of those watermelon stocks against CGMMV infection. For CGMMV inoculation, the leaves of one month old gongdae (T1) were rubbed by carborundum mixed with the CGMMV. A total of 140 plants (T1) were exposed to the CGMMV and we found that ten plants were completely resistant to virus infection. This is the first report that by genetic engineering a cucubitaceae crop resistant to CGMMV infection is ever developed. Further information will be provided in the poster.

• Journal of the Korean Society of Safety
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• v.26 no.2
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• pp.13-19
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• 2011

The magnetic polishing is the useful method to finish using magnetic power of magnet. That method is one of precision polishing techniques and has an aim of the clean technology using for the pure of gas and inside of the clean pipe. The magnetic abrasive polishing method is not so common for machine that it is not spreaded widely. There are rarely researcher in this field because of non-effectiveness of magnetic abrasive. Therefore, in this paper deals with development of the magnetic abrasive using Sr-Ferrite. In this development, abrasive grain GC used to resin bond fabricated low temperature. And Sr-Ferrite of magnetic abrasive powder fabricated that Sr-Ferrite was crused into 200 mesh. The XRD analysis result show that only GC abrasive and Sr-Ferrite crystal peaks detected which explains resin bond was not any more chemical reaction. From SEM analysis it is found that GC abrasive and Sr-Ferrite were strong bonding with each other by bond. The magnetic polishing is performed by polishing the surface of pipe by attracting magnetic abrasives with magnetic fields. This can be widely applied for finishing machinery fabrications such as various pipes and for other safety processes. In this paper, we could have investigated in to the changes of the movement of magnetic abrasive grain. In reference to this result, we could have made the experiment which is set under the condition of the magnetic flux density, polishing velocity according to the form of magnetic brush.