• Title/Summary/Keyword: scratch

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A STUDY ON SURFACE OF VARIOUS ABUTMENT SCREWS

  • Park Chan-Ik;Chung Chae-Heon;Choi Han-Cheol
    • The Journal of Korean Academy of Prosthodontics
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    • v.41 no.3
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    • pp.351-359
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    • 2003
  • Statement of problem: Regardless of any restoration, most of case, we used in screw connection between abutment and implant. For this reason, implant screw loosening has been remained problem in restorative practices. Purpose: The purpose of this study was to compare surface of coated/plated screw with titanium and gold alloy screw and to evaluate physical property of coated/plated material after scratch test in FESEM investigation Material and methods: GoldTite, titanium screw provided by 3i (Implant Innovation, USA) and TorqTite, titanium screw by Steri-Oss (Nobel Biocare, USA) and gold screw, titanium screw by AVANA (Osstem Implant, korea) - were selected for this study. Each abutment screw surface was observed at 100 times, and then screw crest, root, and slope were done more detailed numerical value, at 1000 times with FESEM. A micro-diamond needle was also prepared for the scratch test. Each abutment screw was fixed, micro-diamond scratch the surface of head region was made at constant load and then was observed central region and periphery of fine trace through 1000 times with FESEM. Results: The surface of GoldTite was smoother than that of other kinds of screw and had abundant ductility and malleability compared with titanium and gold screw. The scratch test also showed that teflon particles were exfoliated easily in screw coated with teflon. Titanium screw had a rough surface and low ductility. Conclusion: It was recommended that the clinical use of gold-plated screw would prevent a screw from loosening. CLINICAL IMPLICATIONS Clinical use of gold-plated screw would prevent a screw from loosening because it had abundant ductility and malleability compared with titanium and gold screw.

Utilizing Advanced Pad Conditioning and Pad Motion in WCMP

  • Kim, Sang-Yong;Chung, Hun-Sang;Park, Min-Woo;Kim, Chang-Il;Chang, Eui-Goo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11a
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    • pp.171-175
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    • 2001
  • Chemical mechanical polishing(CMP) process has been widely used to planarize dielectrics and metal, which can apply to employed in integrated circuits for sub-micron technology. Despite the increased use of CMP process, it is difficult to accomplish the global planarization of free-defects in inter level dielectrics and metal. Especially, defects like (micro-scratch) lead to severe circuit failure, and affects yield. Current conditioning method - bladder type, orbital pad motion - usually provides unsuitable pad profile during ex-situ conditioning near the end of pad life. Since much of the pad wear occurs by the mechanism of bladder tripe conditioning and its orbital motion without rotation, we need to implement new ex-situ conditioner which can prevent abnormal regional force on pad caused by bladder-type and also need to rotate the pad during conditioning. Another important study of ADPC is related to the orbital scratch of which source is assumed as diamond grit dropped from the strip during ex-situ conditioning. Scratch from diamond grit damaged wafer severely so usual1y scraped. Figure 1 shows the typical shape of scratch damaged from diamond. We suspected that intensive forces to the edge area of bladder type stripper accelerated the drop of Diamond grit during conditioning, so new designed Flat stripper was introduced.

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Effect of the WC particle size and Co content on the adhesion property between AIP-TiN coating and WC-Co substrate (AIP-TiN/WC-Co계에서 WC입자크기와 Co함량이 밀착력에 미치는 영향)

  • 한대석;류정민;권식철;김광호
    • Journal of the Korean institute of surface engineering
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    • v.35 no.3
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    • pp.165-171
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    • 2002
  • TiN coating were deposited onto different WC-Co substrates using arc ion plating (AIP) technique. The structure and morphology for the deposited coating were characterized by x-ray diffraction (XRD) and scanning electron microscopy (SEM). The adhesion behavior of the deposited TiN coating was investigated with a conventional scratch test. Effects of WC particle size and Co content on the adhesion strength between the deposited TiN coating and substrate were studied. During the scratch test, the value of critical load was dependent of WC particle size and Co content on substrate. As the WC particle size and Co content on substrate decreased, the critical load increased. The highest critical load, approximately 110N, was obtained at WC particle size of 1$\mu\textrm{m}$ and Co content of 10wt.%.

The Characteristics of Painted Coating on Aluminum Sheet by Sending Conditions (알루미늄 판재의 센딩조건에 따른 도장특성 평가)

  • Yoon, Han-Ki;Choi, Seok-In;Lee, Jong-Ho
    • Journal of Ocean Engineering and Technology
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    • v.25 no.1
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    • pp.44-48
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    • 2011
  • Researchers suggested painted coating characteristics of aluminum sheet by various sending condition. Painted coating is used to protect the surface of the blocks from the interior and exterior. It is also used to enhance the value of automobiles and ship materials. This process makes the materials surface for protection and elegance. Although analysis of the roughness and critical scratch load of painted coating is important, the effects of this material have not progressed much. In this study, the characteristics of painted coating in the other conditions of the polished aluminum sheet were investigated. The results of both various conditions and initial roughness values were almost similar to final values after painted coating.

Formability of Non-Vinyl Pre-coated Metal Sheet (Non-Vinyl Pre-coated Metal재의 성형성에 관한 연구)

  • Kim, Dong-Hwan;Kim, Byung-Min
    • Journal of the Korean Society for Precision Engineering
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    • v.18 no.4
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    • pp.121-128
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    • 2001
  • This study has been performed to investigate formability of non-vinyl PCM(pre-coated metal)sheet. First, physical test of PCM sheets were tested to evaluate finish coating characteristic of PCM. And then, test equipment was made for friction test and three non-vinyl PCM sheets were tested by straight pulling method. This paper provides the results of the friction tests showing the influence of sheet surface texture and process conditions. It was found that the influence of contact pressure and speed had an effect upon the level of friction. Also using tests, the scratch resistance of a series of polyester coating has been investigated. This investigation aims to clarify the process conditions that prevent the scratch of PCM to form the good electrical appliances such as microwave oven, air conditioner and refrigerator etc.

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Effects of plasma Immersion ion Implanted and deposited layer on Adhesion Strength of DLC film

  • Yi Jin-Woo;Kim Jong-KuK;Kim Seock-Sam
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2004.11a
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    • pp.301-305
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    • 2004
  • Effects of ion implantation on the adhesion strength of DLC film as a function of ion doses and implanted energies were investigated. Ti ions were implanted on the Si-wafer substrates followed by DLC coating using ion beam deposition method. Adhesion strength of DLC films were determined by scratch adhesion tester. Morphologies and compositional variations at the different ion energies and doses were observer by Laser Microscope and Auger Electron Spectroscopy, respectively. From results of scratch test, the adhesion strength of films was improved as increasing ion implanted energy, however there was no significant evidence with ion dose.

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Deveopement of Scratch Detection Algorithm for ITO coated Glass using Image Processing Technique (화상처리를 이용한 ITO 코팅 유리의 결함검출기법 개발)

  • 김면희;배준영;이태영;안경철;이상룡
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2003.06a
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    • pp.1275-1278
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    • 2003
  • This research describes a image-processing technique for the scratch detecting algorithm for ITO coated glass. The light emitter efficiency of Organic EL has a failing-off in quality due to many causes. One of the many causes was the defects of the surface in ITO coated glass. We use the logical level thresholding method for binarization of gray-scaled glass image. This method is useful to the algorithm for detecting scratch of ITO coated glass automatically without need of any prior information of manual fine tuning of parameters.

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Development and Application of Education Program Art Area Subject-based STEAM for Improvement of Elementary Students' Creativity: With a Scratch Programming Language (초등학생의 창의성 신장을 위한 예술 영역 교과 중심의 STEAM 교육 프로그램 개발 및 적용: 스크래치 프로그래밍 언어를 활용하여)

  • SEO, Youngho;JUNG, Seungbum;KIM, Jonghoon
    • Journal of Fisheries and Marine Sciences Education
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    • v.28 no.1
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    • pp.69-82
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    • 2016
  • In this study, Art area -based STEAM education programs that take advantage of the Scratch was to analyze the effect of the development of elementary school students' creativity. The winter break of ${\bigcirc}{\bigcirc}$ university education donation application students 3, 4, 5th grader was verified two research hypothesis to the target. First, Art area -based STEAM education programs will be effective on the development of elementary school students' creativity. Second, Art area -based STEAM education programs will be more effective on the development of the elementary school girls' creativity than the elementary school boys' creativity. Art area -based STEAM education programs is to show a significant difference on the development of elementary school students' creativity, mean change of elementary school girls were remarkable than boys.

Evaluation of Head/Disk interface using TAA Signal (TAA신호를 이용한 하드디스크의 헤드/디스크 인터페이스 분석)

  • Park, Yong-Sik;Lee, Jae-Mo;Kim, Dae-Eun
    • Journal of the Korean Society for Precision Engineering
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    • v.18 no.3
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    • pp.107-114
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    • 2001
  • The durability of head/disk interface is an important issue for hard disk drives. Currently, there are several means of assessing the performance and integrity of the head/disk interface. In this work Track Average Amplitude(TAA) signal was used to analyzed the head/disk interface with respect to variations in disk velocity, slider pre-load and preformed scratch on the disk. Particularly, TAA variation due to disk defect in the form of a scratch was investigated.

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Encryption Program using Scratch (스크래치 기반의 암호화 프로그램)

  • Hur, Tai-Sung;Lee, Min-Jae;Kim, Ga-Gyeom
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2018.07a
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    • pp.331-332
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    • 2018
  • 일반적으로 정보를 전달함에 있어 정보의 유출은 큰 문제이다. 정보를 전달하는 방법이 발달하고 보편화됨에 따라 오늘날에 와서는 개인정보 유출과 관련된 문제가 지속적으로 대두되었다. 개인정보의 보호가 더욱 중요하게 생각되는 현 상황을 고려하여 스크래치(Scratch)의 기본 연산기능을 이용한 한글과 특수문자, 영어 암호화(Encryption) 및 복호화(Decryption)를 가능하게 하고, 정수 형태의 2개의 개인키와 간단한 알고리즘을 통해 암호문을 생성하는 어플리케이션을 통해 암호화와 복호화에 대한 개념을 학습하고, 더욱 나아가 개인정보 보호에 대한 중요성을 상기할 수 있도록 하였다.

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