• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.433-434
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• 2009

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.06a
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• pp.239-240
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• 2007

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.163-164
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• 2010

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.787-788
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• 2011

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.3 no.1
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• pp.38-44
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• 2004

An internal finishing process by the application of magnetic abrasive machining has been developed as a new technology to obtain a fine inner surface of non-ferromagnetic pipe. In this paper, an abrasive slurry circulation system was designed and manufactured. As a result, it was found that a fine inner surface of pipe was available by the use of these machining methods. The basic machining characteristics of pin-type magnetic tools were analyzed experimentally. In addition, the experimental results show that pin-type magnetic tools have more machining efficiency than Iron particles as magnetic tools.

• Laser Solutions
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• v.18 no.3
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• pp.6-8
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• 2015

Finishing process includes deburring, polishing and edge radiusing. It improves the surface profile of specimen and eliminates the alien substance on surface. Deburring is the elimination process for debris of edges. Polishing lubricates surfaces by rubbing or chemical treatment. There are two types for electron finishing. The one is using pulse beam. The other is using the convergent and scanning electron beam. Pulse type device appropriates the large area process. But it does not control the beam dosage. Scanning type device has advantages for dosage control and edge deburring. We design the convergence and scan type. It has magnetic lenses for convergence and scan device for scanning beam. Magnetic lenses consist of convergent and objective lens. The lenses are designed by the specification(beam size and working distance). In this paper, we evaluate the convergence performance by pattern process. Also, we analysis the results and important factors for process. The important factors for process are beam size, pressure, stage speed and vacuum. These results will be utilized into systematizing pattern shape and the factors.

• Restorative Dentistry and Endodontics
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• v.18 no.1
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• pp.114-121
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• 1993

The purpose of this study was to evaluate the effect on treatment methods to shear bond strength between composite resin and amalgam when the alloy surface was finished with a diamond wheel or an sandblaster. Forty round acrylic cylinders were fabricated with a diameter of 33mm and a height of 20mm to fit into the device used during shear bond strength testing. A round undercut cavity (diameter, 8mm: depth, 2.5mm) was prepared in the center of the acrylic surface and the cavity was restored using a amalgam. A total of 40 acrylic cylinders with amalgam were divided into 4 groups according to treatment method. The group treatment were as follows : Group 1 : acid etching after finishing the amalgam with diamond wheel Group 2 : no acid etching after finishing the amalgam with diamond wheel Group 3 : acid etching after sandblasting the amalgam Group 4 : no acid etching after sandblasting the amalgam The shear bond strength of composite resin bonded to amalgam of each specimen was tested with a universal testing machine at a crosshead speed of 0.5mm/min and 500kg in full scale. The results were as follow: 1. After diamond finishing, the non-acid etching group had highest shear bond strength with 7.29kg/$cm^2$ and after sandblasting, the acidetching group had lowest shear bond strength with 4.49kg/$cm^2$. 2. In both diamond finishing and sandblasting group, acid etching of the roughened amalgam surface decreased the shear bond strength. 3. The group treated with a diamond wheel had higher shear bond strength those treated with an sandblaster but there was not significanat.

• Restorative Dentistry and Endodontics
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• v.32 no.2
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• pp.138-150
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• 2007

The purpose of this study was to evaluate the difference of surface roughness of composite resin according to composite resin type, polishing methods, and use of resin sealant. Two hundred rectangular specimens, sized $8{\times}3{\times}2mm$, were made of Micro-new (Bisco, Inc., Schaumburg, IL, U.S.A) and Filtek Supreme (3M ESPE Dental Products, St. Paul, MN, U.S.A.), and divided into two groups; Micronew-M group, Filtek Supreme-S group. Specimens for each composite group were subdivided into five groups by finishing and polishing instruments used; M1 & S1(polyester strip), M2 & S2 (Sof-Lex disc), M3 & S3 (Enhance disc and polishing paste), M4 & S4(Astropol) and M5 & S5 (finishing bur), Polished groups were added letter B after the application of resin surface sealant (Biscover), eg, M1B and S1B. After specimens were stored with distilled water for 24hr, average surface roughness (Ra) was taken using a surface roughness tester. Representative specimens of each group were examined by FE-SEM (S-4700: Hitachi High Technologies Co., Tokyo, Japan). The data were analysed using paired t-test, ANOVA and Duncan's tests at the 0.05 probability level. The results of this study were as follows ; 1. The lowest Ra was achieved in all groups using polyester strip and the highest Ra was achieved in M5, S5 and M5B groups using finishing bur. On FE-SEM, M1 and S1 groups provided the smoothest surfaces, M5 and S5 groups were presented the roughest surfaces and voids by debonding of filler on the polished specimens. 2. There was no significant difference in Ra between Micronew and Filtek Supreme before the application of resin sealant, but Micronew was smoother than Filek Supreme after the application of resin sealant. 3. There was significant corelation between Ra of type of composite resin and polishing methods before the application of resin sealant (p=0.000), but no significant interaction between them after the application of resin sealant. On FE-SEM, most of composite resin surfaces were smooth after the application of resin sealant on the polished specimens. 4. Compared with before and after the application of resin sealant in group treated in the same composite and polishing methods, Ra of M4B and M5B was statistically lower than that of M4 and M5, and S5B was lower than that of S5, respectively (p<0.05). In conclusion, surface roughness by polishing instruments was different according to type of composite resin. Overall, polyester strip produced the smoothest surface, but finishing bur produced the roughest surface. Application of resin sealant provided the smooth surfaces in specimens polished with Enhance, Astropol and finishing bur, but not provided them in specimens polished with Sof-Lex disc.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.4
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• pp.39-46
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• 2017

The experimental research was conducted to evaluate the adhesive performance of surface finishing material with primer based on silane(primer). For this purpose, concrete specimens with compressive strength of 18, 30, 50 MPa were made and cured in water condition ($20{\pm}2^{\circ}C$) for 28 days. A primer was applied on the age of 28 days and evaluated according to based on the curing age of the surface finishing material. Moreover, the mortar specimen also made and tested as per KS F 4937 for compared with concrete-based test results. Test results indicated that the adhesive strength of specimens with primer exhibit similar than that of specimens without primer. Also, the adhesive performance improved with increasing in curing age and compressive strength. The correlation between compressive and adhesive strength of mortar and concrete specimens showed similar trend. It was noted that there is no significant effects of primer on adhesive performance of surface finishing material, thus use of primer has superior potential for solving durability problem of concrete slab surface.

• Journal of the Korea Furniture Society
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• v.20 no.3
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• pp.232-238
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• 2009

In designing furniture and interior accessories, a computer graphic program is normally used over the whole process of manufacturing furniture from idea stage to actual manufacturing stage. It especially play an important role in the modeling process which comes before actual manufacturing stage. in such modeling process, the most important part is expression of quality of material used and surface treatment method. Expression of material quality of wood and surface finishing just like an actual picture enable the designers to analogize the feeling of furniture and interior accessories more exactly over the whole process of actual manufacturing and such a result has positive effect on development field of furniture and accessories.