• Title/Summary/Keyword: Fabrication Technique

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Fabrication of Polymeric Optical Waveguide by LIGA (LIGA공정을 이용한 정밀 고분자 광도파로 제작)

  • Kim, Jin-Tae;Kim, Byeong-Cheol;Choi, Choon-Gi;Yoon, Keun-Byoung;Jeong, Myung-Yung
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.27 no.6
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    • pp.997-1006
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    • 2003
  • LICA technique evolved as a basic fabrication process fur micro-structure. The present report deals with the basic technological features in the sequence of the LIGA technique such as deep x-ray lithography(DXRL), electroplating, and moulding processes at Pohang Light Source (PLS). We designed 3-D structured master for fabrication of polymeric optical wavegude and manufactured polymeric optical wavegude with the same using hot embossing process. Polymeric optical waveguide could be produced with ${\pm}$ 1 $\mu\textrm{m}$ accuracy and good surface roughness.

Fabrication of three dimensional microstructures using laser direct writing technique (레이저묘화 기술을 이용한 3차원 미세구조물 제조)

  • 정성호;한성일
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2003.06a
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    • pp.670-673
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    • 2003
  • Fabrication of three dimensional microstructures by laser-assisted chemical vapor deposition of material is investigated. To fabricate microstructures, a thin layer of deposit in desired patterns is first written using laser direct writing technique and on top of this layer a second layer is deposited to provide the third dimension normal to the surface. By depositing many layers. a three dimensional microstructure is fabricated. Optimum deposition conditions for direct writing of initial and subsequent layers with good surface quality and profile uniformity are determined. Using an arson ion laser and ethylene as the light source and reaction gas, respectively, fabrication of three-dimensional carbon microstructures is demonstrated.

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Fabrication of a metal-ceramic crown to fit an existing partial removable dental prosthesis using ceramic pressed to metal technique: a clinical report

  • Seo, Jae-Min;Ahn, Seung-Geun
    • The Journal of Advanced Prosthodontics
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    • v.6 no.3
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    • pp.241-244
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    • 2014
  • Fabricating a crown to retrofit an existing abutment tooth for a partial removable dental prosthesis (PRDP) is one of the most time-consuming and labor-intensive clinical procedures. In particular, when the patient is concerned with esthetic aspects of restoration, the task of fabricating becomes more daunting. Many techniques for the fabrication of all-metallic or metal-ceramic crowns have been discussed in the literature. This article was aimed to describe a simple fabrication method in which a retrofitting crown was fabricated for a precise fit using a ceramic-pressed-to-metal system.

Use of temporary filling material for index fabrication in Class IV resin composite restoration

  • Kim, Kun-Young;Kim, Sun-Young;Kim, Duck-Su;Choi, Kyoung-Kyu
    • Restorative Dentistry and Endodontics
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    • v.38 no.2
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    • pp.85-89
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    • 2013
  • When a patient with a fractured anterior tooth visits the clinic, clinician has to restore the tooth esthetically and quickly. For esthetic resin restoration, clinician can use 'Natural Layering technique' and an index for palatal wall may be needed. In this case report, we introduce pre-restoration index technique on a Class IV defect, in which a temporary filling material is used for easy restoration. Chair-side index fabrication for Class IV restoration is convenient and makes a single-visit treatment possible.

Fabrication of nanometer scale patterning by a scanning probe lithography (SPL에 의한 나노구조 제조 공정 연구)

  • Ryu J.H.;Kim C.S.;Jeong M.Y.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.10a
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    • pp.330-333
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    • 2005
  • The fabrication of mold fur nano imprint lithography (NIL) is experimentally reported using the scanning probe lithography (SPL) technique, instead of the conventional I-beam lithography technique. The nanometer scale patterning structure is fabricated by the localized generation of oxide patterning on the silicon (100) wafer surface with a thin oxide layer, The fabrication method is based on the contact mode of scanning probe microscope (SPM) in air, The precision cleaning process is also performed to reach the low roughness value of $R_{rms}=0.084 nm$, which is important to increase the reproducibility of patterning. The height and width of the oxide dot are generated to be 15.667 nm and 209.5 nm, respectively, by applying 17 V during 350 ms.

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ANALYSIS OF THE PROCESS OF FABRICATION OF STEEL STRUCTURES USING AN AUTOMATIC CONSTRUCTION SYSTEM

  • Hak-Ju Lee;Yoonseok Shin;Wi Sung Yoo;Hunhee Cho;Kyung-In Kang
    • International conference on construction engineering and project management
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    • 2009.05a
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    • pp.1081-1087
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    • 2009
  • An automatic construction system in Korea is now at the stage of the full automation like in Japan, and an actual pilot project is going to be built in 2009. However, in developing a new construction system that has never been implemented before, there is a need to assess the performance and to consider the uncertainty of the system. The program evaluation and review technique (PERT) allows dealing with this uncertainty. Thus, this paper implements an analysis of the process of steel fabrication and makes suggestions for time-related problems arising from the analysis. The time required for steel erection by the automatic system was compared with that in the traditional method. In the result, finding out another construction process and improving robot performance were proposed to resolve the problems. The results will contribute to promoting the development of an efficient system for the new automatic construction system.

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Development of Biomimetic Scaffold for Tissue Engineering (조직공학을 위한 생체모사용 스캐폴드 개발)

  • Park, Su-A;Lee, Jun-Hee;Kim, Wan-Doo
    • Elastomers and Composites
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    • v.44 no.2
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    • pp.106-111
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    • 2009
  • Tissue engineering is a research field for artificial substitutes to improve or replace biological functions. Scaffolds play a important role in tissue engineering. Scaffold porosity and pore size provide adequate space, nutrient transportation and cell penetration throughout the scaffold structure. Scaffold structure is directly related to fabrication methods. This review will introduce the current technique of 3D scaffold fabrication for tissue engineering. The conventional technique for scaffold fabrication includes salt leaching, gas foaming, fiber bonding, phase seperation, melt moulding, and freeze drying. These conventional scaffold fabrication has the limitations of cell penetration and interconnectivity. In this paper, we will present the solid freeform fabrication (SFF) such as stereolithography (SLA), selective laser sintering (SLS), and fused deposition modeling (FDM), and 3D printing (3DP).

Role of span length in the adaptation of implant-supported cobalt chromium frameworks fabricated by three techniques

  • Zhou, Ying;Li, Yong;Ma, Xiao;Huang, Yiqing;Wang, Jiawei
    • The Journal of Advanced Prosthodontics
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    • v.9 no.2
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    • pp.124-129
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    • 2017
  • PURPOSE. This study evaluated the effect of span length on the adaptation of implant-supported cobalt chromium frameworks fabricated by three techniques. MATERIALS AND METHODS. Models with two solid abutment analogs at different inter-abutment distances were digitized using a laboratory scanner. Frameworks of two-, three-, and four-unit fixed prostheses were designed by a computer. Six dots with a diameter of 0.2 mm were preset on the surface of each framework. A total of 54 implant-supported cobalt chromium frameworks were fabricated by milling, selective laser melting (SLM), and cast techniques. The frameworks were scanned and exported as Stereolithography files. Distances between two dots in X, Y, and Z coordinates were measured in both the designed and fabricated frameworks. Marginal gaps between the framework and the abutments were also evaluated by impression replica method. RESULTS. In terms of distance measurement, significant differences were found between three- and four-unit frameworks, as well as between two- and four-unit frameworks prepared by milling technique (P<.05). Significant differences were also noted between two- and three-unit frameworks, as well as between two- and four-unit frameworks prepared by cast technique (P<.05). The milling technique presented smaller differences than the SLM technique, and the SLM technique showed smaller differences than the cast technique at any unit prostheses (P<.05). Evaluation with the impression replica method indicated significant differences among the span lengths for any fabrication method (P<.05), as well as among the fabrication methods at any unit prostheses (P<.05). CONCLUSION. The adaptation of implant-supported cobalt chromium frameworks was affected by the span length and fabrication method.