• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.257-257
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• 2013

4세대 방사광가속기를 2014년 말 건설 완공 목표로 언듈레이터 시제품 제작하여 테스트 진행과정에 있다. 좁은 틈의 언듈레이터를 지나가는 펄스전자의 진행이 잘되려면 낮은 임피던스가 요구되는데, 전자의 진행을 방해하는 주요 요인으로 진공 표면 거칠기와 산화층 두께에 영향을 많이 받는다. 이러한 영향을 줄이기 위하여 연질의 알루미늄 6063-T6를 재료로 압출공정에 혼합가스를 주입하여 표면 산화를 최소화하였다. 본 실험은 6 m 압출형 진공용기에 압출공정만 거친 것과 유체연마 메디아 종류별, 크기별, 처리시간에 따른 표면개선 효과와 산화층 변화를 알아보았다. 그리고 최종 유체연마 메디아제거 과정에 경면 연마된 표면에 2차 스크레치가 발생하는 원인을 진단하고 이를 방지하기 위한 알코올 주입형 정압시스템을 개발한 것을소개한다.

• Proceedings of the KAIS Fall Conference
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• 2011.05b
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• pp.974-976
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• 2011

수석을 가공하기 위해서 회전 통 안에 피연마물을 투입하고 이를 회전 시키면 피연마물 자체의 마찰과 동체와의 마찰로 연마가 된다. 본 연구는 복수의 석재가 회전드럼에 투입되고 회전드럼이 회전을 하면 회전드럼 내측 벽에 개별적으로 고정되어있는 폐비닐로 이루어져있는 패드가 복수의 석재를 회전드럼이 회전하는 방향으로 견인하여 회전드럼에 투입된 복수의 석재가 서로 충돌하여 석재의 거친 면이나 날카로운 모서리가 부드럽게 연마될 수 있도록 하고, 폐비닐로 이루어져있는 패드는 석재에 발생되는 충격을 흡수하고 기존의 패드보다 강도를 크게 향상시키고 훼손된 패드만 교체할 수 있도록 고안하였다.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.7
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• pp.73-84
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• 1999

An advanced expert system for supporting automatic polishing operation of mold and die has been developed. The goal of this system is to minimize the polishing time, the number of polishing and tools used. Also, this paper proposes the advanced concept of the polishing method to perform polishing operation of mold and die, and it has adapted to the orthogonal array method. as a statistical technique, to choose an optimal polishing condition. An expert system consists of the polishing machining database that includes the information of workpiece and polishing tools, and the input/output module.

• Restorative Dentistry and Endodontics
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• v.36 no.2
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• pp.119-124
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• 2011

Objectives: The purpose of this experiment was to evaluate four different polishing systems of their polishability and polishing time. Materials and Methods: 4 mm diameter and 2 mm thickness Teflon mold was made. Z-250 (3M ESPE) hybrid composite resin was slightly overfilled and pressed with slide glass and cured with Optilux 501 for 40 sec each side. Then the surface roughness (glass pressed: control group) was measured with profilometer. One surface of the specimen was roughened by #320 grit sand paper and polished with one of the following polishing systems; Sof-Lex (3M ESPE), Jiffy (Ultradent), Enhance (Dentsply/Caulk), or Pogo (Dentsply/Caulk). The surface roughness and the total polishing time were measured. The results were analyzed with one-way ANOVA and Duncan's multiple range test. Results: The surface roughness was lowest in Pogo, and highest in Sof-Lex. Polishing times were shortest with Pogo, and followed by the Sof-Lex, Enhance and Jiffy. Conclusions: One-step polishing system (Pogo) is very effective to get the smooth surface in a short time, therefore it can be recommended for final polishing system of the restoration.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.1
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• pp.98-107
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• 2004

Proper finishing/polishing of dental restorations are critical clinical procedures that enhance both esthetics and longevity of restored teeth. This study was to compare the effects of immediate and delayed finishing/polishing procedures on the surface roughness and surface hardness of tooth-colored restoratives including two microfilled composite resins, such as Filtek A110 and Silux Plus, two hybrid composite resins, such as Revolution formular2 and Palfique Estelite. A total of 48 specimens were made for each material. The first 16 specimens served as the control group and the remaining 32 specimens were randomly divided into two equal groups. The control group was stored in distilled water at $37^{\circ}C$ for 1 week after light polymerization against the Mylar sheet. The first experimental group was finished/polished immediately after light polymerization and stored for 1 week in distilled water at $37^{\circ}C$, whereas the while the second group was finished/polished 1 week after light polymerization and stored in distilled water at $37^{\circ}C$. The results were as follows: 1. The smoothest surface was produced by Mylar sheet and finishing/polishing procedure increased the surface roughness. However, the surface roughness of composite resins were not influenced by the finishing/polishing timing. 2. There were significant differences about surface roughness between Revolution formular 2 and Silux Plus, regarding immediate finishing/polishing, and between Palfique Estelite and Silux Plus regarding delayed finishing/polishing(p<0.05). 3. The sequence of the surface hardness was ascending order by Revolution formular 2, Silux Plus, Filtek A110 and Palfique Estelite. However there were no significant differences about hardness among the control group and two finishing/polishing timing groups. 4. The effects of finishing/polishing time on surface roughness and hardness appeared to be material-dependent.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.3
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• pp.1620-1625
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• 2015

In this study, a variety of industrial gears, shafts, chains, rollers, mold, etc. are widely used inautomotive steel carbon steel for machine structural SM45C typical material used for the experiments. In order to cure the surface of the test piece after the rough grinding and fine grinding was performed in order polishing. Perform the surface hardening of SM45C lacal area by using a diode laser. The output of the laser diode and the feed rate to the process variable. Micro-hardness testing, microstructure testing, scanning electron microscope testing(SEM), the heat input to the analysis. After analyzing the experiment to compare the mechanical properties of the material. When using a diode laser to assess the soundness of the surface hardening. Accordingly, the process for deriving the optimum demonstrate the feasibility.

• Restorative Dentistry and Endodontics
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• v.33 no.1
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• pp.1-8
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• 2008

The purpose of this study was to evaluate the effect of a new resin monomer, filler size and polishing technique on the surface roughness of composite resin restorations using confocal laser scanning microscopy. By adding new methoxylated Bis-GMA (Bis-M-GMA, 2,2-bis[4-(2-methoxy-3-methacryloyloxy propoxy) phenyl] propane) having low viscosity, the content of TEGDMA might be decreased. Three experimental composite resins were made: EX1 (Bis-M-GMA/TEGDMA = 95/5 wt%, 40 nm nanofillers); EX2 (Bis-M-GMA/TEGDMA = 95/5 wt%, 20 nm nanofillers); EX3 (Bis-GMA/TEGDMA = 70/30 wt%, 40 nm nanofillers). Filtek Z250 was used as a reference. Nine specimens (6 mm in diameter and 2 mm in thickness) for each experimental composite resin and Filtek Z250 were fabricated in a teflon mold and assigned to three groups. In Mylar strip group, specimens were left undisturbed. In Sof-lex group, specimens were ground with #1000 SiC paper and polished with Sof-lex discs. In DiaPolisher group, specimens were ground with #1000 SiC paper and polished with DiaPolisher polishing points. The Ra (Average roughness), Rq (Root mean square roughness), Rv (Valley roughness), Rp (Peak roughness), Rc (2D roughness) and Sc (3D roughness) values were determined using confocal laser scanning microscopy. The data were statistically analyzed by Two-way ANOVA and Tukey multiple comparisons test (p = 0.05). The type of composite resin and polishing technique significantly affected the surface roughness of the composite resin restorations (p < 0.001). EX3 showed the smoothest surface compared to the other composite resins (p < 0.05). Mylar strip resulted in smoother surface than other polishing techniques (p < 0.05). Bis-M-GMA. a new resin monomer having low viscosity, might reduce the amount of diluent, but showed adverse effect on the surface roughness of composite resin restorations.

• Restorative Dentistry and Endodontics
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• v.31 no.4
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• pp.312-322
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• 2006

The objectives of this study were to evaluate the effect of surface roughness on the surface color and translucency of the composite resins. Two composite resins (Esthet-X, Dentsply, Milford, USA and Charisma, Kulzer, Domagen, Germany) were used to investigate the surface color. Charisma was used to investigate the translucency. 40 disc samples (diameter: 8 mm, thickness: 5 mm) were made by each product to measure the surface color. Polymerized each sample's one side was treated by Sof-Lex finishing and polishing system (Group C, M, F, SF). 40 disc samples (diameter: 6 mm, thickness: 1 mm) were prepared to measure the opacity. 1 mm samples were ground one side with #600, #1000, #1500 and #2000 sandpapers. CIE $L^{*}a^{*}b^{*}$ values of each 5 mm thickness samples, and XYZ values of 1 mm thickness samples on the white and black background were measured with spectrophotometer (Spectrolino, GretagMacbeth, Regensdorf, Switzerland). Mean surface roughness (Ra) of all samples before and after surface treatment was measured using the Surface Roughness Tester SJ-301 (Mytutoyo, Tokyo, Japan). Regardless of type and shade of the composite resin, $L^{*}$ values measured in group C were higher than others (p < 0.05), and $L^{*}$ value decreased as the Ra value decreased except B3 shade of Esthet-X. But there were no significant difference in $a^{*}$ values among groups. In control group and SF, highest $b^{*}$ values were measured (p < 0.05), except B1 shade of Esthet-X. Contrast ratio decreased as the Ra value decreased (p < 0.05). With the above results, difference of surface roughness has influence on surface color and translucency of dental composite resins.

• Journal of Dental Rehabilitation and Applied Science
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• v.39 no.4
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• pp.195-203
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• 2023

Purpose: This study aimed to evaluate the influence of surface sealants on the surface roughness of composite resins. Materials and Methods: The study used microfilled composite resin (Metafil CX, Sun Medical Co.) and hybrid composite resin (Aelite^TM LS posterior, Bisco). Sixty specimens (8 mm in diameter and 4 mm in height) of each composite resin type were prepared and divided into 3 groups. Each specimen was ground with 600, 1000, and 2000-grit sandpaper. The Surface roughness (Ra) values were measured using a surface roughness tester (SJ-301, Mytutoyo) before and after surface sealant application. Surface sealants, BisCover^TM LV (Bisco), Optiguard^® (Kerr), and Seal-n-Shine^TM (Pulpdent), were applied to the specimens, as instructed and observed by scanning electron microscope (JSM-7500, JEOL) and atomic force microscope (MultiMode IV, Veeco Instruments). Results: Specimens ground with 600-grit sandpaper coated with surface sealants exhibited significantly lower Ra values than the untreated group (P < 0.05). Specimens ground with 1000 and 2000-grit sandpaper showed statistically no difference. There was no significant difference in surface roughness among BisCover^TM LV, Optiguard^®, and Seal-n-Shine^TM. SEM and AFM revealed remarkably decreased microdefects on the surfaces of composite resins after surface sealant application. Conclusion: Surface sealants can influence surface roughness when applied on the rough surface of composite resins but not on highly polished composite resins.

• 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.