• Title/Summary/Keyword: Shaping

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Experimental Cutting Performance Evaluation of LGP using Vibration Assisted High Speed Shaping (도광판의 고속 진동절삭 특성에 관한 연구)

  • Kang, DongBae;Ahn, JungHwan;Son, SeongMin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.4
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    • pp.1871-1878
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    • 2014
  • PMMA (Polymethyle-methacrylate) optical components have recently been increasingly used as one of the important part of the high precision equipments. This research presents comparatively the surface preparation of light incident plane, LIP (Light Incident Plane) of LGP (Light Guide Panel) by end milling, high speed shaping, and vibration assisted high speed shaping. From several experiments, the results show that the surface quality was improved in high speed shaping and the vibration assisted HSS show not only decreasing waviness and breakage also raising the straightness property. For applying high speed shaping and vibration assisted HSS, an additional tool post was developed and experimentally used.

Comparison of shaping ability using LightSpeed, ProTaper and Hybrid technique in simulated root canals (모조 레진블락 근관에서 LightSpeed, ProTaper 및 Hybrid technique의 성형 효율 비교)

  • Kang, Soon-Il;Kwak, Sang-Won;Park, Jeong-Kil;Hur, Bock;Kim, Hyeon-Cheol
    • The Journal of the Korean dental association
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    • v.47 no.7
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    • pp.444-454
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    • 2009
  • The purpose of this study was to compare the shaping abilities of LightSpeed, ProTaper-Universal, and hybrid technique using S-series of ProTaper-Universal and LigthSpeed. The 72 simulated root canals of J-shape were used and classified as flowing 3 groups according to the instrumentation methods; Group P of 24 canal blocks were prepared with ProTaper-Universal, Group L was prepared with LightSpeed, and Group H was prepared with hybrid technique (initial shaping with ProTaper-Universal SI and S2 and apical shaping with LightSpeed from #25 to #50). A second-year resident of Endodontic department prepared the resin block canals to apical size #50 (F5 in Group P). The time lapses for instrumentation and the reduction of root canal curvature after shaping were measured. The pre- and post-instrumented root canals were scanned and superimposed to evaluate and calculate the increased canal width and apical centering ratio. The results were as followings: Group Land H showed significant less instrumentation time than Group P (p < 0.05). The ProTaper system showed greater reduction of root canal curvature and working length diminishment than other methods (p < 0.05). LightSpeed system showed best canal curvature preserving characteristics. The Group P had greater instrumented widths at all levels examined (p < 0.05). Group L and Group H showed lower centering ratio (ability to preserve the canal center; the lower ratio means the better canal center preservation) than Group P (p < 0.05). Group H had the lowest centering ratio at the 1 mm level.

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Shaping Formation and Behaviour Characteristic for SCST Structure by Cable-tensioning (Cable-tensioning에 의한 SCST 구조의 형상 형성과 거동 특성)

  • Kim, Jin-Woo;Kwon, Min-Ho
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.28 no.6A
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    • pp.819-825
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    • 2008
  • This paper describes the shaping formation and the erection of SCST structure by cable-tensioning. It could be a fast and economical method for constructing the space structure consisted with uniform pyramids by cable-tensioning of the cable in bottom chords. In the initial layout, the top chords and web members are left at their true length, the bottom chords are given gaps in proportion to the desired final shape. The feasibility of the proposed shaping method and the reliability of the established geometric model were confirmed with nonlinear finite element analysis and an experimental investigation on small scale and full size test models. As a result, the behaviour characteristic of MERO joint is very significant in shaping analysis of space structure. This study suggests the most reasonable modeling technique for the prediction of shaping in practices. And it is shown the characteristic of the behavior in shaping test for practical design purposes.

COMPARISON OF CANAL SHAPING METHODS WITH GTTM ROTARY FILE AND CONDENSATION METHODS (GT rotary file을 이용한 근관성형법과 충전방법의 비교)

  • Kang, Yu-Mi;Jin, Jeong-Hee;Yu, Mi-Kyung;Lee, Se-Joon;Lee, Kwang-Won
    • Restorative Dentistry and Endodontics
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    • v.27 no.5
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    • pp.521-529
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    • 2002
  • The purpose of this study was to compare the shaping time of two shaping methods and the leakage of three different obturation techniques. Ninty three canaled human molar teeth were used, which were randomly divided into two groups of forty teeth each and ten control teeth. After working length determination, the one group was prepared crown-down technique using rotary root canal instruments of GT rotary files .12/20, .10/20, .08/20 and .06/20 taper(Maillefer Instrument SA. Switzerland). The other group was instrumented with Gates Glidden burs(#1, #2, and #3) to coronal preparation and GT rotary files .08/20 and .06/30 taper to apical preparation. Shaping time was measured. After root canals were instrumented, they were divided to three subgroups and obturated as follows : Subgroup 1, obturated with single cone method Subgroup 2, obturated with lateral condensation : Subgroup 3, obturated with continuous wave technique. Three subgroups were obturated using non-standardized gutta-percha cone(Diadent, Korea, .06 or .08 taper) and AH-26(Dentsply DeTrey, Germany) as a root canal cement. Ten unobturated teeth served as positive and negative controls. After immersion in 2% methylene blue solution for 1 month, the teeth were washed during 24h. The teeth were demineralized in 10% nitric acid and dehydrated by immersion in 80, 90 and 100% ethyl alcohol. The teeth were finally cleared and stored in 100% methylsalicylate, and apical dye penetration was evaluated under stereomicroscope(Leica M420, LC, U.S.A)at $\times$8.75 magnification. Liner measurement of dye penetration was assessed with the use of digitalized image analysing system (analySIS, GmbH, Germany) The data were analysed statistically using independent T-test and Two-way ANOVA and Tukey test. The result were as follows 1. In canal prepared with GT$^{TM}$ rotary file, shaphing time taked more than the group of using Gates Glidden drill to coronal preparation without statistical significance (p>0.05) 2. The group of single cone obturation using canal preparation of GT$^{TM}$ rotary files showed significantly more apical leakage than those of lateral condensation and continuous wave technique regardless of shaping method (p<0.05). 3 The group of single cone obturation using canal preparation of GT$^{TM}$ rotary files and Gates Glidden drill showed significantly more apical leakage than those of continuous wave technique regardless of shaping method (p<0.05). 4. Regardless of shaping method, The group of continuous wave obturation showed less apical leakage than those of lateral condensation without statistical significance (p>0.05). 5. The group of single cone obturation using canal preparation of GT$^{TM}$ rotary files and Gates Glidden drill showed more apical leakage than the group of lateral condensation using same shaping method with-out statistical significance (p>0.05).

The Effects of Paralanguage Utilization Training for Audiobook Text Shaping - Professor's Friendly Behavior as a Parameters - (유사언어 활용 훈련이 오디오북 텍스트 형상화에 미치는 영향 연구 - 교수자의 우호적 행동을 매개변수로 -)

  • Cho, Ye-Shin
    • Journal of Korea Entertainment Industry Association
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    • v.14 no.2
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    • pp.141-153
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    • 2020
  • The purpose of study is to examine the role of the Professor's friendly behavior as a parameters in the course of Paralanguage Utilization Training using pronunciation, stress, voice tone, speed, pause and expression of feelings affecting of Audiobook text shaping. the results of this study will be a reference to training on the use of Paralanguage for dynamic shaping of Audiobook text and recognizing the need and influence of professors' friendly behavior as a parameters. The results of the study are as follows. First, training in the use of Paralanguage was shown to have a positive effect on the Shaping of Audiobook text and served as a key factor in conveying the original meaning of text. Therefore, if we look at the significance and content of training using Paralanguage and continue training using Paralanguage, it will actually help to shape Audiobook text. Second, the professor's friendly behavior partially acted as a parameters role between training in the use of Paralanguage and shaping Audiobook text. The professor's friendly behavior has helped form Audiobook text by providing a sense of trust and will increase the level of completion for training in the use of Paralanguage. Thus, training in the use of Paralanguage Utilization Training could result in more effective Audiobook text shaping when conducted in conjunction with the professors' friendly actions. Therefore, it was shown that the ability to use Paralanguage and the professor's caring and friendly behavior to help them perform better were more effective when they simultaneously affected Audiobook text shaping.