• 대한치과기공학회지
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• 제24권1호
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• pp.65-71
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• 2002

This study was performed to observe the microhardness change of the surface and the bonding strength between the porcelain and alloy specimens in order to investigate the effects of appended indium, tin and copper on interfacial properties of Au-Pd-Ag alloys. The hardness of castings was measured with a micro-Vicker's hardness tester. The interfacial shear bonding strength between alloy specimen and fused porcelain was measured with a mechanical testing system(MTS 858.20). The microhardness of Au-Pd-Ag alloy was increased by adding indium and tin, but not increased by adding copper. The shear bonding strength of Au-Pd-Ag-Sn alloy and Au-Pd-Ag-Cu alloy showed 87MPa, 57MPa. The higher concentration of adding elements showed the higher shear bonding strength.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2005년도 춘계학술발표대회 개요집
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• pp.393-395
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• 2005

The bonding for Aluminum and Copper in the air is investigated in this study. This bonding method does not include the special process of removing aluminum oxide films. In case of this bending, each metal Is heated at bonding temperature where is above eutectic temperature of Al-Cu system and below melting point of Aluminum. The liquefaction around the bonding surface occurs after the diffusion at solid state of each metal. This phenomenon is predicted by the temperature range above eutectic temperature of Al-Cu equilibrium phase diagram.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.830-833
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• 2003

This paper describes the fabrication and characteristics of 3C-SiCOI sotctures by SDB and etch-back technology for high-temperature MEMS applications. In this work, insulator layers were formed on a heteroepitaxial 3C-SiC film grown on a Si(001) wafer by thermal wet oxidation and PECVD process, successively. The pre-bonding of two polished PECVD oxide layers made the surface activation in HF and bonded under applied pressure. The wafer bonding characteristics were evaluated by the effect of HF concentration used in the surface treatment on the roughness of the oxide and pre-bonding strength. Hydrophilic character of the oxidized 3C-SiC film surface was investigated by ATR-FTIR. The strength of the bond was measured by tensile strengthmeter. The bonded interface was also analyzed by SEM. The properties of fabricated 3C-SiCOI structures using etch-back technology in TMAH solution were analyzed by XRD and SEM. These results indicate that the 3C-SiCOI structure will offers significant advantages in the high-temperature MEMS applications.

• Restorative Dentistry and Endodontics
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• 제22권1호
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• pp.209-219
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• 1997

The research of the dentin bonding system was mainly on the chemistry and bonding strength. And in vitro assessement of biocompatibility of dentin bonding system was not completely developed. The purpose of this study was to evaluate the cytotoxic effect of several dentin primers. Scotchbond Multi-Purpose (3M Dental Products. USA). Gluma (BayerDental. Germany). All-Bond (Bisco. USA). ProBond (CaulkDensply, USA) and VeridonFil (Dongyang Nylon. Korea) were included. Cytotoxicity was tested using MTT cell viability test. 0.5 ul. 1 ul. 2 ul and 10 ul of each primer were added to the 96 well plate of incubated L929 cell lines. After 30-minute. 1. 4. 24 and 72-hour exposures. absorbance of L929 cells was observed with ELISA reader. All data were analyzed using t-test. All primers showed cytotoxicity on L929 cells under every conditions used in this study. Absorbance of L929 cells was decreased by time. Scotch bond group exhibited the lowest absorbance value in all exposure time and value.

• 대한치과의사협회지
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• 제11권3호
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• pp.171-175
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• 1973

A 9-year-old girl, in good health, presented a horizontal impaction of the upper left central incisor. History revealed that the patient had been involved in a trauma of the maxillary anterior portion during her childhood. This impacted tooth crown, which was exposed surgically, was bonded by plastic attachments of direct bonding system, and was carefully tried to induce on the dental arch. On the process of the orthodontic treatment the tooth was completely induced and in normal alignment on the arch. The treatment result was very satisfactory; color, vitality, and mobility were normal, periodontal support was good and the cosmetic result was excellent.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.808-812
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• 2003

We need a lot of manpower and we can cut down a labor cost by applying industrial robots the footwear bonding automation process. In this study, we suggest how to program off-line robot path along a shoe's outsole shape in the footwear bonding process by 5-axis microscribe system like robot arms. This microscribe system development consists 5-axis microscribe mechanics, signal processing circuit, and PC with software. It is the system for making database of a shoe's outsole through the movement of a microscribe with many joints. To do this, first read 5-encoders' pulse values while a robot arm points a shoe's outsole shape from the initial status. Then, calculate a relative shoe's outsole by Denavit-Hatenberg's (D-H) direct Kinematics of known length of links and coordinate values. Next, calculate the encoders' pulse values of the robot arm's rotation and transmitting the angle pulse values to the PC through a circuit. Finally, it is able to display a shoe's outsole at real-time by computing the Denvavit-Hantenberg's (D-H) direct kinematics in the PC. With the coordinate values calculated above, we can draw a bonding gauge-line on the upper. Also, we can make off-line robot path programming compute a shoe's bonding area on the upper. These results will be effectively applied for programming a robot path on off-line and automatically.

• 한국통신학회논문지
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• 제36권5A호
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• pp.536-542
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• 2011

FCC는 디지털 방송 전환 후 발생되는 TVWS에서의 효율적인 스펙트럼 활용을 위해 비면허 시스템의 주파수 사용을 허용하였다. 다양한 면허 사용자 및 비면허 CR 사용자가 공존하는 환경에서 최적 채널 선택을 위해서는 우선 채널 사용 현황 파악이 요구된다. 데이터베이스를 통해 제공되는 면허 사용자 채널 정보 외에는 센싱 알고리즘을 통한 검출이 필요한데 본 논문에서는 단일 채널 수신만으로 채널 본딩된 비면허 CR 신호까지 검출할 수 있는 알고리즘을 제안하였다. 전산 모의 실험 결과 IEEE 802.11af 신호는 단일 채널의 경우에는 SNR=-18dB, 8 채널 본딩 신호의 경우에는 SNR=-7dB에서 검출 확률이 90% 이상으로 나타났으며, 동일 조건에서 ECMA 392 신호는 단일 채널의 경우에는 SNR=-14dB, 8 채널 본딩 신호의 경우에는 SNR=-6dB로 나타났다. 결과적으로 제안 알고리즘을 통해 단일 채널 수신만으로 채널 본딩 신호의 검출이 가능해짐으로써 전채널 센싱 소요 시간의 감소 및 시스템 오버헤드를 줄일 수 있을 것으로 기대된다.

• 대한치과기공학회지
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• 제33권1호
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• pp.47-54
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• 2011

Purpose: To investigate shear bonding strength between dental zirconia ceramics with different surface treatment and metal bracket. Methods: Zirconia ceramics(LAVA, 3M ESPE, USA) were divided to 4 groups according to their surface treatment; no surface treatment(G1), sand blasting(G2), silane coating(G3), and sand blasting+silane coating(G4). Specimens were bonded to metal bracket using resin bond($Transbond^{TM}XT$, 3M Unitek, USA). Shear bond strength was measured using universal test machine(3366 INSTRON. U.S.A) with cross head speed of 1 mm/min. Microstructural investigation for fracture surface was performed after shear test. Results: Shear bonding strengths of single surface treatment groups (G2 and G3) were higher than no treatment group(G1). Combined Treatment Group (G4) showed the highest shear bond strength of 9.15MPa. Microstructural observation shows that higher shear bonding strength was obtained when debonding was occurred at metal bracket/resin interface rather than zirconia ceramic/resin interface. Conclusion: Surface treatment of zirconia is necessary to obtain higher bonding strength. Combined treatment can be more effective when surface the surfaces are kept clean and homogeneous.

• 구강회복응용과학지
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• 제32권4호
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• pp.293-300
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• 2016

목적: 중합방식과 화학적 조성이 다른 본딩제들이 자가중합형 비스아크릴 임시수복 재료의 결합에 미치는 영향을 알아 보고자 하였다. 연구 재료 및 방법: 원반 형태의 비스아크릴 임시수복 재료 시편 40개를 준비한 후 본딩제의 중합특성에 따라 대조군을 포함 4개의 군으로 나누었다. 본딩제 도포 후 직경 4 mm의 원형 구멍을 가진 4 mm 두께의 테플론 몰드를 이용하여 동일한 비스아크릴 임시수복 재료을 첨상하였다. 전단결합강도시험을 시행하였으며 파절면을 현미경으로 관찰하였다. 일원배치 분산분석과 Tukey 사후분석을 사용하여 유의수준 0.05로 검증하였다. 결과: 화학중합형 본딩제를 사용한 군에서 통계적으로 유의한 가장 높은 전단결합강도를 보였으며($27.36{\pm}4.30 MPa$, P < 0.05) 모든 시편에서 비스아크릴 임시수복 재료 내에서 파절이 일어나는 응집성 파절 양상을 보였다(100%). 실험군중 가장 낮은 값은 광중합형 본딩제를 사용한 군에서 기록되었으며($13.29{\pm}2.56 MPa$) 이는 대조군과 거의 유사한 값을 보였다. 동일한 광중합 방식 이지만 화학중합 레진과의 호환성을 높인 본딩제를 사용한 군에서는 광중합형 본딩제를 사용한 군에 비해 통계적으로 유의하게 높은 값을 보였다(P = 0.043). 결론: 본딩제의 종류가 수리된 비스아크릴 임시수복 재료의 전단결합 강도에 영향을 주며, 비스아크릴 임시수복 재료의 수리 시 적절한 본딩제 선택이 중요하다.

• Restorative Dentistry and Endodontics
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• 제25권2호
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• pp.243-253
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• 2000

The purpose of this in vitro study was to evaluate dentin bonding by two different dentin bonding systems(DBS) using acetone based primer or adhesive [All Bond 2(AB2), One Step(OS)] when they were applied by wet or dry bonding technique. Morphology of resin-dentin interface and hybrid layer thickness(HLT) were investigated using Confocal Laser Scanning Microscope(CLSM) and compared to shear bond strength(SBS). 72 extracted sound human molars were randomly divided into 4 groups of 18 teeth each - Group 1.(AW); AB2 by wet bonding. Group 2(AD); AB2 by dry bonding. Group 3.(OW); OS by wet bonding, Group 4.(OD); OS by dry bonding. In 6 teeth of each group, notch-shaped class V cavities(depth 2mm) were prepared on buccal and lingual surface at the cementoenamel juction(12 cavities per group). To obtain color contrast in CLSM observation, bonding resins of each DBS were mixed with rhodamine B and primer of AB2 was mixed with sodium fluorescein. Prepared teeth of each group were treated with AB2, OS, respectively according to the manufacturer's instructions except for dentin surface moisture treatment after acid etching. In group 1 and 3, after acid etching, excess water was removed with wet tissue(Kimwipes), leaving consistently shiny, visibly hydrated dentin surface. In group 2 and 4, dentin surface was dried for 10 seconds at 1 inch distance. The treated teeth were then packed with composite resin(${\AE}$litefil) and light-cured. 12 microscopic samples($60{\sim}80{\mu}m$ thickness) of each group were obtained after longitudinal section and grinding(Exakt cutting and grinding system). Morphological investigation of resin-dentin interface and HLT measurement using CLSM were done. For measurement of SBS, remaining 12 teeth of each group were flattened occlusally to remove all enamel and grinded to 500 grit SiC(Pedemet Specimen Preparation Equipment). After applying DBS on the exposed dentin surface, composite resin was applied in the shape of cylinder, which has 5mm diameter, 1.5mm thickness, and light cured. SBS was measured using Instron with a crosshead speed of 0.5mm/min. It was concluded as follows, 1. HLT of AW(mean: $2.59{\mu}m$) was thicker than any other group, and followed by AD, OW, OD in descending order(mean; 2.37, 2.28, $1.92{\mu}m$). Only OD had statistically significant differences(p<0.05) to AW and AD. 2. There were intimate contact of resin and dentin at the interface in wet bonding groups, but gaps or irregular interfaces were observed in dry bonding groups. 3. The length, diameter, density of resin tags were various even in the same group without significant differences between groups and lots of adhesive lateral branches were observed. 4. There were no statistically significant difference of SBS between AB2 and OS, but SBS of wet bonding groups were significantly higher(p<0.05) than dry bonding groups. 5. There were no consistent relationships between HLT and SBS.