• 제목/요약/키워드: interlocking mechanism

검색결과 30건 처리시간 0.022초

"황제내경(黃帝內經)" "음양교(陰陽交)" 병해석(病解析) (Study on Eum-yang Interlocking in "Hwangjenaegyeong(黃帝內經)")

  • 국보조;김효철
    • 대한한의학원전학회지
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    • 제23권4호
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    • pp.31-33
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    • 2010
  • The earliest record of 'Eum-yang Interlocking(陰陽交)' is in "Hwangjenaegyeong(黃帝內經)". In this article, we reviewed the meaning of the two Chinese Characters 'On'(溫) and "Gyo"(交), discussed the meaning, mechanism and treatment principles of Eum-yang Interlocking and Three Incurable Symptoms in order to provide a theoretical basis for treating the warm febrile disease in modern times.

Frictional Behavior of Solid and Hollow Cylinders in Contact Against a Porcine Intestine Specimen

  • Kim, Young-Tae;Kim, Dae-Eun;Park, Suk-Ho;Yoon, Eui-Sung
    • KSTLE International Journal
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    • 제7권2호
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    • pp.51-55
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    • 2006
  • In order to design an effective foot surface which can provide adequate friction for a self-propelled medical microrobot moving inside the small intestine, frictional mechanisms between the small intestine inner wall and the foot surface of the robot must be understood. In this paper, mechanical interlocking effect was considered to design the surface of the foot that can generate the desired frictional force. The concept of the design was derived from the hookworm that lives inside the small intestine. Hookwarms are known to adhere to the small intestine wall by interlocking with villi on the surface of the small intestine. The interlocking mechanism was considered as the main frictional mechanism for the design of the microrobot foot surface in this work. 2 mm and 6 mm diameter solid and hollow cylindrical shaped foot specimens were designed and tested to assess the frictional force between the specimens and the porcine small intestine specimen.

노후 매립관로로 인한 지하 공동발생 메카니즘 고찰 (Understanding of Subsurface Cavity Mechanism due to the Deterioration of Buried Pipe)

  • 이대영;조남각
    • 한국지반공학회논문집
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    • 제32권12호
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    • pp.33-43
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    • 2016
  • 노후관로로 인한 지반내 공동형성과 지반이완 메카니즘을 분석하기 위해 현장시험을 수행하였으며 수치해석을 수행하여 현장시험과 비교하였다. 현장시험은 지반내 인위적인 공동을 만들기 위해 얼음을 이용하였으며, 시간경과에 따른 얼음의 융해로 인해 공동형성과 주변지반의 이완을 확인할 수 있었다. 다짐된 토사의 interlocking에 의한 이완 및 공동형성 거동을 고려하기 위하여개별요소법에 근거한 수치해석 프로그램인 PFC 2D를 이용하였다. PFC의 클럼프(clump) 요소를 도입하여 불규칙 형상의 입자를 모사하였으며, 이를 통해 얻은 공동형성과 지반이완 특성을 현장시험 결과와 비교함으로써 지반내 공동형성 및 거동특성을 파악하였다.

전단시험 중 모래입자의 변형에 관한 연구 (Study on the Evolution of Sand Structure during Shearing)

  • 이석원
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2000년도 봄 학술발표회 논문집
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    • pp.289-296
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    • 2000
  • This paper summarizes the results of a study which has quantified the evolution of the structure of sands adjacent to geomembranes of varying roughness at different stages of shearing. The results show that the structure evolution, and hence shear mechanisms for rounded uniform sands adjacent to geomembranes, are directly influenced by the surface roughness of the geomembranes. For smooth geomembranes, the shear mechanism predominantly involves sliding of sand particles and only affects the sand structure within two particle diameters of the geomembrane. For slightly textured geomembranes, the effects of interlocking and dilation of sand particles extends the zone of evolution to four particles diameters from the interface. For moderately/heavily textured geomembranes, the interlocking and dilation of sand particles is fully developed and results in large dilation in the interfacial zone, which extends up to six particle diameters from the interface. By understanding how the structure of the sand adjacent to geomembranes of different roughness changes during shearing, it may be possible to identify alternative geomembrane roughening procedures and patterns that can lead to more efficient interface designs.

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초고강도 콘크리트에서 전기로 산화 슬래그 잔골재 사용에 의한 강도 증진 기구 (Mechanism of Strength Development in Ultra High Strength Concrete Using the Electric Arc Furnace Oxidizing Slag as Fine Aggregate)

  • 이승헌;임두섭;이승훈;이주하
    • 콘크리트학회논문집
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    • 제25권1호
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    • pp.3-9
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    • 2013
  • 초고강도 콘크리트에서 잔골재로 세척사 대신에 전기로 산화 슬래그를 사용했을 경우, 재령 91일 압축강도가 약 15 MPa 정도 향상되었다. 압축강도가 향상된 원인을 규명하기 위해 잔골재의 Ca 성분 용출 특성을 고찰하였고, 잔골재와 페이스트 계면에서의 미세조직, 기공율, 미소경도 및 Ca/Si 몰비를 검토하였다. 그리고 잔골재 형상에 의한 강도 증진 효과를 알아보기 위해 잔골재의 표면 거칠기를 AFM으로 측정하였다. 실험 결과, 초고강도 콘크리트에서 전기로 산화 슬래그 잔골재 사용에 의한 강도 증진 기구는 화학적 기구와 물리적 기구로 구분할 수 있다. 화학적 기구로는, 전기로 산화 슬래그에서 함유되어 있는 가용성 Ca 성분이 용출되어 잔골재와 페이스트 사이에 반응생성물을 형성시켜 조직을 치밀화 시킴으로 잔골재-페이스트간의 부착력을 증진 시키는 것으로 나타났다. 그리고 물리적 기구로는, 전기로 산화 슬래그 잔골재는 세척사에 비해 표면의 굴곡도가 2배 정도 커서, 잔골재와 페이스트 간의 interlocking strength를 증가시킴으로서 압축강도 발현에 기여하는 것으로 판단했다.

Discrete element modelling of geogrids with square and triangular apertures

  • Chen, Cheng;McDowell, Glenn;Rui, Rui
    • Geomechanics and Engineering
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    • 제16권5호
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    • pp.495-501
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    • 2018
  • Geogrid application that has proved to be an effective and economic method of reinforcing particles, is widely used in geotechnical engineering. The discrete element method (DEM) has been used to investigate the micro mechanics of the geogrid deformation and also the interlocking mechanism that cannot be easily studies in laboratory tests. Two types of realistically shaped geogrid models with square and triangle apertures were developed using parallel bonds in PFC3D. The calibration test simulations have demonstrated that the precisely shaped triangular geogrid model is also able to reproduce the deformation and strength characteristics of geogrids. Moreover, the square and triangular geogrid models were also used in DEM pull-out test simulations with idealized shape particle models for validation. The simulation results have been shown to provide good predictions of pullout force as a function of displacement especially for the initial 30 mm displacement. For the granular material of size 40 mm, both the experimental and DEM results demonstrate that the triangular geogrid of size 75 mm outperforms the square geogrid of size 65 mm. Besides, the simulations have given valuable insight into the interaction between particle and geogrid and also revealed similar deformation behavior of geogrids during pullout. Therefore, the DEM provides a tool which enable to model other possible prototype geogrid and investigate their performance before manufacture.

Ni 본드코팅이 Al 기지에 고온 용사 코팅된 Fe 코팅층의 접합특성에 미치는 영향 (Effect of Ni Bond Coat on Adhesive Properties of Fe Coating Thermal Sprayed on Al Substrate)

  • 권의표;김대영;이종권
    • 한국재료학회지
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    • 제26권10호
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    • pp.542-548
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    • 2016
  • The influence of NiCrAlY bond coating on the adhesion properties of an Fe thermal coating sprayed on an Al substrate was investigated. By applying a bond coat, an adhesion strength of 21MPa was obtained, which was higher than the 15.5MPa strength of the coating without the bond coat. Formation of cracks at the interface of the bond coat and the Al substrate was suppressed by applying the bond coat. Microstructural analysis of the coating interface using EBSD and TEM indicated that the dominant bonding mechanism was mechanical interlocking. Mechanical interlocking without crack defects in the coating interface may improve the adhesion strength of the coating. In conclusion, the use of an NiCrAlY bond coat is an effective method of improving the adhesion properties of thermal sprayed Fe coatings on Al substrates.

모니터용 유연 승강의 스프링 설계에 관한 연구 (A Study on the Spring Design of Smooth Lifting System for Monitor)

  • 정선환;최성대;변용근;최은환
    • 한국기계가공학회지
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    • 제4권4호
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    • pp.48-53
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    • 2005
  • This research is materialized the mechanism of a interlocking elevator device to meet with customer's requirement demanding a variety of function. On this suitably theoretical translation and by considering of material significance of the most factor's tension spring and torsion spring, it's compared and reviewed the stress's calculation according that SWC and SWPB applied differently. And also that is approved through actual experiment. Out of a variety of feasible movement. Torque Balance is materialized by combination of tension spring, torsion spring and disk spring. So that application of 3 factors for optimal design is very important factor. In future, this research thesis make sure to play a highly role for application and improvement mechanically in various industry sector out of materializing interlock.

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Desmear 습식 표면 전처리가 무전해 도금된 Cu 박막과 FR-4 기판 사이의 계면 접착 기구에 미치는 영향 (Effect of Desmear Treatment on the Interfacial Bonding Mechanism of Electroless-Plated Cu film on FR-4 Substrate)

  • 민경진;박영배
    • 한국재료학회지
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    • 제19권11호
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    • pp.625-630
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    • 2009
  • Embedding of active devices in a printed circuit board has increasingly been adopted as a future electronic technology due to its promotion of high density, high speed and high performance. One responsible technology is to embedded active device into a dielectric substrate with a build-up process, for example a chipin-substrate (CiS) structure. In this study, desmear treatment was performed before Cu metallization on an FR-4 surface in order to improve interfacial adhesion between electroless-plated Cu and FR-4 substrate in Cu via structures in CiS systems. Surface analyses using atomic force microscopy and x-ray photoemission spectroscopy were systematically performed to understand the fundamental adhesion mechanism; results were correlated with peel strength measured by a 90o peel test. Interfacial bonding mechanism between electrolessplated Cu and FR-4 substrate seems to be dominated by a chemical bonding effect resulting from the selective activation of chemical bonding between carbon and oxygen through a rearrangement of C-C bonding rather than from a mechanical interlocking effect. In fact, desmear wet treatment could result in extensive degradation of FR-4 cohesive strength when compared to dry surface-treated Cu/FR-4 structures.

고강도 시멘트 경화체의 강도 및 파괴인성에 관한 연구 (A Study on the Strength and Fracture Toughness of High Strength Hardened Cement Paste)

  • 김정환
    • 콘크리트학회지
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    • 제6권6호
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    • pp.151-158
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    • 1994
  • 본 연구에서는 수경성 시멘트 경화체의 구조적 결함인 휨강도를 향상시키시 위해 보통 포틀랜드 시멘트비를 0.1로 하여 혼합수량을 줄이고 수용성 고분자 물질인 Hydroxy Propy Methyl Cellulose(HPMC)를 첨가하여 시멘트입자의 윤활작용에 따른 균일한 분산효과와 결합효과를 얻도록 하였으며, twin roll mill로 혼련 성형하여 치밀하고 균일한 경화제 시편을 제조하였다. 이러한 고강도 시멘트 경화체의 휨강도는 약 96MPa, 탄성계수는 60GPa로 우수한 특성을 나타내었다. 고강도 시멘트의 고강도화 기구는 100${\mu}m$ 이상의 큰 기공제거 및 균열성장경로인 모세관 기공의 감소, 미수화 시멘트의 증가로 인한 탄성계수의 증가와 crack toughening(입자 가교, 고분자 섬유 가교, frictional interlocking)에 의한 파괴 인성의 향상 때문인 것으로 판단된다.