• 제목/요약/키워드: Root contact

검색결과 172건 처리시간 0.021초

반도체 장비 히터로드 유착 개선에 관한 연구 (A Study on Improvement of Heater Rod Adhesion in Semiconductor Equipment)

  • 왕현철;서화일
    • 반도체디스플레이기술학회지
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    • 제19권1호
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    • pp.67-72
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    • 2020
  • This study analyzes the method of adhesion and improvement between heat.er and RF filter in PE-CVD equipment through TRIZ method and proposes a solution. TRIZ Solution such as function analysis, 9-window matrix, ASIT, and Root cause analysis were used. The contact temperature between the heater and the RF filter was 20% and the surface temperature was lowered to 5.7℃, suggesting an improvement method for the thermal expansion of the PE-CVD equipment hot zone.

Unified Approach for Force/Position Control in the Vehicle Body Sanding Process

  • Nguyen, Chi Thanh;Lee, Jae Woo;Yang, Soon Yong
    • 드라이브 ㆍ 컨트롤
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    • 제14권3호
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    • pp.25-31
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    • 2017
  • This study presents a methodology for simulating a unified approach that controls interaction force between tool and objective by using a synthesis method of robot interacting control law for stabilizing the transient process of motion. Root locus is used to analyze stabilization of motion deviation characteristics. Based on responses of motion deviation, contact force is derived to satisfy exponential stability and we generate control input with respect to motion trajectories and interaction force. Moreover, simulation is applied to experimental application of a Cartesian robot driven by two stepper motors, and the noise of feedback signals is considered as presence of system inaccuracies, and the unified approach of interaction force control is examined precisely.

라미네이트 치아형성 디자인에 관한 문헌고찰 (Tooth preparation design of dental laminate veneer: a review article)

  • 조은혜;고경호;박찬진;조리라;허윤혁
    • 구강회복응용과학지
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    • 제32권3호
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    • pp.149-157
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    • 2016
  • 성공적인 라미네이트 치료를 위해서는 치아형성 방법이 매우 중요하다. 법랑질에 국한된 보존적인 치아형성, 치태조절이 용이한 치은연선상(equigingival) 변연, 가능한 존재하는 접촉점의 유지 등의 조건이 일반적으로 알려져 있으나 구체적인 치아형성 디자인에 관하여는 논쟁의 여지가 존재한다. 생역학적으로 고려해볼 때, 다음과 같은 사항들이 추천된다. 절단면 피개는 심미적 요구와 전방유도의 재설정 필요 여부 측면에서 결정해야 하며, 법랑질 두께가 충분한 경우에는 구개측 연장을 하는 것이 좋으나 응력 집중이 큰 구개오목(palatal concavity)에 변연이 위치하는 것은 부적절하다. 인접면 연장은 증례에 따라 선택적으로 시행하며, 인접면에 레진수복물이 존재하는 경우에는 표면처리 후 레진 수복물을 절반 이상 피개하는 형태의 라미네이트로 수복한다. 변색이 심하지 않은 근관치료가 시행된 치아의 경우 라미네이트 수복을 고려해 볼 수 있으며, 이 때 섬유강화레진 포스트를 사용하는 것을 추천한다.

양호한 Finishing을 위한 이론적 근거 및 기준 (Rationale and criteria for excellent finishing)

  • 유영규;김영준
    • 대한치과교정학회지
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    • 제29권6호
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    • pp.637-648
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    • 1999
  • 교정 치료 후 이상적인 교합과 양호한 심미적 결과를 얻기 위해서 일반적으로 교정 장치 제거하기 4개월에서 7개월 전에 detailing을 시행한다. 이와 같은 과정을 finishing이라고 하며, 이 과정은 최종적인 양호한 결과를 얻는데 있어서 필수적이다. 일부 교정의는 finishing을 위한 특별한 이론적 근거 및 기준 없이 이 과정을 교정 치료의 마지막 단계에서 시행하면 되는 것으로 여기고 있다. 그러나, 최종적인 양호한 교정 치료 결과를 얻기 위해서는finishing 과정이 총 치료 계획의 부분으로 치료의 초기 단계에서부터 고려되어야만 하며, 교정 장치 제거를 위한 이론적 근거 및 기준에 근거한 finishing을 위한 checklist가 필요하다. 이 checklist는 크게 네 부류로 분류할 수 있다. 즉, 교합 요인, 심미적 요인, 치주적 요인과 습관적 요인으로 분류할 수 있다. 교합 요인에서 점검해야할 요소로는 alignment, marginal ridge discrepancy, interproximal contact, anterior inclination, posterior inclination, overjet, overbite, arch form과 functional occlusion 등이 있다. 심미적 요인에는 gingival form, crown form, crown width과 crown length 등이 있다. 치주적 요인에는 root angulation, bone level 등이 있다. 습관적 요인에는 mouth breathing, tongue position at rest, tongue thrust habit, lip biting, nail biting과 finger sucking 등이 있다.

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풍력터빈용 고속단 헬리컬 기어의 치형 최적화에 관한 연구 (A Study on Optimization of Tooth Micro-geometry for Wind Turbine High Speed Stage Helical Gear Pair)

  • 조성민;이도영;김래성;조상필;류성기
    • 한국기계가공학회지
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    • 제13권5호
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    • pp.15-20
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    • 2014
  • The wind industry grew in the first decade of the 21st century at rates consistently above 20% a year. For wind turbine, gearbox failure can be extremely costly in terms of repair costs, replacement parts, and in lost power production due to downtime. In this paper, gear tooth micro-modification for the high speed stage was used to compensate for the deformation of the teeth due to load and to ensure a proper meshing to achieve an optimized tooth contact pattern. The gearbox was firstly modeled in a software, and then the various combined tooth modification were presented, and the prediction of transmission under the loaded torque for the helical gear pair was investigated, the normal load distribution and root stress were also obtained and compared before and after tooth modification under one torque. The simulation results showed that the transmission error and normal load distribution under the load can be minimized by the appropriate tooth modification. It is a good approach where the simulated result is used to improve the design before the prototype is available for the test.

생물방제균 Pseudomonas stutzeri YPL-1의 형질전환 조건 (Transformation of Antagonistic Pseudomonas stutzeri YPL-1 against Root Rotting Fungi Fusarium solani by Plasmid DNA)

  • 김용수;김상달
    • 한국미생물·생명공학회지
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    • 제18권5호
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    • pp.454-459
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    • 1990
  • 식물근부균 Fusarium solani의 생육을 강력히 길항하는 생물방제균 Pseudomonas stutzeri YPL-1에 외부유전자 도입을 통한 유전공학적 육종방법의 기초를 확립하고자 하였다. 이를 위해 plasmid pKT230을 vector로 하여 형질전환의 가능성을 조사하였으며 이때, 혈질전환에 필요한 최적조건을 조사한 결과 P.stutzeri YPL-1의 형질전환에는 대수증식기 초기의 균체가 가장 적합하였고, 20mM RbCl과 100mM $CaCl_2$를 함유한 냉각용액에 1${\mu}g$/ml의 plasmid DNA를 첨가하였을 때 최대의 형질전환 빈도를 나타내었다. 또한 plasmid DNA와 competent cell를 혼합한 후 $0^{\circ}C$에서 60분간 처리하는 것이 가장 효과적이었으며 이와 같은 조건에서 형질전환 빈도는 2~$6 \times 10^{-6}$으로 나타났다.

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유한요소법에 의한 Post와 Core 형성법의 비교 (A COMPARISON OF POST AND CORE TECHNIQUES WITH FINITE ELEMENT ANALYSIS)

  • 정용기;허복;이희주
    • Restorative Dentistry and Endodontics
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    • 제21권1호
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    • pp.70-86
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    • 1996
  • The purpose of this study was to analyze the stress distribution in mandibular second premolars restored with different post and core techniques. Sixteen two-dimensional finite element model of mandibular second premolars restored with post and core and complete crown were developed according to the diameter, length, and material of post and core. Vertical force, 10N in magnitude, was applied first to the central fossa and then $45^{\circ}$ oblique force of same magnitude was applied to the buccal contact surface of buccal cusp. The obtained results were as follows : 1. Stress distribution within the dentin 1) Regardless of the material of the post and core and the diameter and length of the post, the pattern of stress distribution within the dentin was similar. 2) Maximum dentinal stress was observed on the lingual root surface of alveolar crest level with oblique loading and on lingual side of root dentin at the crown margin on vertical loading. 3) Cast post and cores produced the lowest dentinal stress concentrations and the highest stress concentration was observed in composite resin post and cores. 2. Stress distribution within the post and core 1) Within the amalgam and composite resin post and core, the patterns and maximum values of stress were similar. Maximum stress located at the central fossa of core portion on vertical loading and at the lingual junction of post and core with oblique loading. 2) Among the all post and cores, the cast post and core registered the highest stress concentration and maximum stress value within the post. Maximum stress located at the post apex on vertical loading and at lingual half of the post surface with oblique loading. 3) In case of Para-post and amalgam core, maximum stress located at the central fossa of core portion and lingual tip of the post head on vertical loading. With oblique loading, maximum stress located at the lingual half of the post surface.

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Kinetic studies using a linear regression analysis for a sorption phenomenon of 17a-methyltestosterone by Salvinia cucullata in an active plant reactor

  • Adnan, Fahrizal;Thanasupsin, Sudtida Pliankarom
    • Environmental Engineering Research
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    • 제21권4호
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    • pp.384-392
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    • 2016
  • The aim of this study was to investigate the removal efficiency of $17{\alpha}$-methyltestosterone (MT) from aqueous solution by Salvinia cucullata Roxb. ex Bory in an active plant-based reactor with a specific focus on linear regression analysis for the sorption phenomena of MT onto the plant roots. A high performance liquid chromatographic method using UV detection (245 nm) was used to analyse the samples. The batch experiments of the active plant reactor (APR) were established to investigate the ability of Salvinia cucullata to remove MT from the liquid phase. The results revealed that 40% and 60% removal of MT from the liquid phase was observed at 5 min. and at 4 h, respectively. Salvinia cucullata can effectively remove MT from the aqueous solution in APRs. Kinetic studies revealed that the sorption phenomena of MT by Salvinia is best described using a linearized pseudo - second order model. Based on the kinetic parameters, it is likely that during the first 4 h of the contact (t = 0 to t = 4 h) sorption is the major driving mechanism of the disappearance of MT from aqueous solutions. However, at higher MT concentrations, diffusivity of MT has a significant effect on the migration of MT from the bulk stream to the root surface. The isotherm analysis revealed that the sorption kinetics favourably followed pseudo second-order. The results of isotherm analysis have indicated that the sorption of MT onto the root surfaces of Salvinia cucullata was favourable and almost irreversible.

석곡(石谷) 이규준(李圭晙)의 "석공산고(石谷散稿)"번역 연구(I) (A Study on The "Seokgoksango(石谷散稿)" of Lee Gyujun(李圭晙)(I))

  • 권오민;박상영;안상영;한창현;안상우
    • 대한한의학원전학회지
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    • 제22권3호
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    • pp.161-185
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    • 2009
  • This article looks into Lee Gyujun(李圭晙)'s life course, Confucian thoughts, and philosophical ideas on the Medicine of Boosting Yang by translating selectively his "Seokgoksango(石谷散稿)". Translating his works is a pre-requisite in order to fully understand the significance of boosting-yang theory in the historical landscape of Korean medicine, not just to comprehend the Medicine of Boosting Yang. First, it is found through the translation that a previous version of "Seokgoksango" had been probably printed before its existing version 1981. Secondly, there are numerous resistants to the Japanese ruling of Korea among his friendship. Thirdly, his academical root came from the Gihohakpa(畿湖學派) - the Giho school of Korean Seongli Confucianism[朝鮮性理學]. Its genealogy in Gyeongsang(慶尙) province is as follows: Lee Yi(李珥), Song Siyeol(宋時烈), Hong Jikpil(洪直弼), Seo Changyu(徐贊奎) and Lee Gyujun(李圭晙), and last, he kept contact with the Toegyehakpa(退溪學派), the Toegye school of Korean Seongli Confucianism, even though his academic root was closely linked to the Giho school. If the entire parts of "Seokgoksango" is translated, it will serve as invaluable historical document to understand a medical unfolding around the 20th century in Korea.

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인볼류트 스퍼기어 설계용 자동화 프로그램 개발 (Development of Automative Program for Designing Involute Spur Gear)

  • 서정덕;정성원;권순구;박종민;최원식;김종순;권순홍
    • 한국기계가공학회지
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    • 제12권6호
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    • pp.142-151
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    • 2013
  • This study develops an automation system for metallic mold design that is applicable in forging non-axial symmetric parts. The metallic mold design program is used to design the metallic mold using two-dimensional axial symmetric metallic molds and to predict the stress concentration using finite element analyses. Then, the program redesigns the metallic mold using variables such as the optimal split diameter, maximum allowable inner pressure, fit tolerance, and stress distribution, which are calculated using the metallic mold design program. When the involute spur gear is forged, stress concentration occurs on the tooth root bounded at the symmetric surface. The SCM4 material is suitable for metallic molds because the stress is less than the yield strength of the insert and it acts on the tooth root regardless of the inner pressure. The metallic mold for forging non-axial symmetric parts can be designed through adjusting the magnitude of the contact pressure. The program developed in this study can be applied to metallic mold designs in involute spur gears of forging, which is an ordinary non-axial symmetric part.