• 제목/요약/키워드: drill design

검색결과 123건 처리시간 0.018초

인조골에서 식립 방법이 교정용 미니 임플란트의 기계적 안정성에 미치는 영향에 대한 예비연구 (The effects of different pilot-drilling methods on the mechanical stability of a mini-implant system at placement and removal: a preliminary study)

  • 조일식;추혜란;김성균;신윤섭;김덕수;김성훈;정규림;존황
    • 대한치과교정학회지
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    • 제41권5호
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    • pp.354-360
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    • 2011
  • Objective: To investigate the effects of different pilot-drilling methods on the biomechanical stability of self-tapping mini-implant systems at the time of placement in and removal from artificial bone blocks. Methods: Two types of artificial bone blocks (2-mm and 4-mm, 102-pounds per cubic foot [102-PCF] polyurethane foam layered over 100-mm, 40-PCF polyurethane foam) were custom-fabricated. Eight mini-implants were placed using the conventional motor-driven pilot-drilling method and another 8 mini-implants were placed using a novel manual pilot-drilling method (using a manual drill) within each of the 2-mm and 4-mm layered blocks. The maximum torque values at insertion and removal of the mini-implants were measured, and the total energy was calculated. The data were statistically analyzed using linear regression analysis. Results: The maximum insertion torque was similar regardless of block thickness or pilot-drilling method. Regardless of the pilot-drilling method, the maximum removal torque for the 4-mm block was statistically higher than that for the 2-mm block. For a given block, the total energy at both insertion and removal of the mini-implant for the manual pilot-drilling method were statistically higher than those for the motor-driven pilot-drilling method. Further, the total energies at removal for the 2-mm block was higher than that for the 4-mm block, but the energies at insertion were not influenced by the type of bone blocks. Conclusions: During the insertion and removal of mini-implants in artificial bone blocks, the effect of the manual pilot-drilling method on energy usage was similar to that of the conventional, motor-driven pilot-drilling method.

4족 보행 로봇을 활용한 달의 직선절벽(Rupes Recta)의 단층면 탐사를 통한 구름의 바다(Mare Nubium) 지역의 지질학적 형성 연구 (Lunar Exploration Employing a Quadruped Robot on the Fault of the Rupes Recta for Investigating the Geological Formation History of the Mare Nubium)

  • 홍익선;이유;주광혁
    • 우주기술과 응용
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    • 제1권1호
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    • pp.64-75
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    • 2021
  • 달이나 지구의 특정 지역의 지질학적 형성 과정을 이해하는 가장 쉬운 방법은 지층이 쌓이는 순서인 층서를 관측하는 것이다. 층서를 분석하면 과거의 지질학적 사건과 그 시기의 유추가 가능하다. 달의 바다 중 구름의 바다(Mare Nubium)에는 층서를 관측할 수 있는 Rupes Recta라는 기울기 10° - 30°의 단층 지형이 있으며, 이 지역의 여건상 바퀴로 움직이는 로버는 탐사가 불가능하기 때문에 원활한 탐사를 위해 경사로와 험지 이동도 무난히 수행 가능한 4족 보행 로봇을 사용해야만 한다. 4족 보행 로봇으로 단층면을 탐사하려면 층서의 구현정도, 지형의 경사도, 지형의 거친 정도인 석리(texture)와 장애물의 유무를 고려하여 탐사 경로를 설계할 필요가 있다. 본 논문에서는 기존 화성 탐사선들의 원격 탐사 자료를 활용하여 최적화된 탐사 경로 선정과정을 제시한다. 그리고 4족 보행 로봇을 활용한 단층면 탐사에 필요한 필수탑재체로 층서의 실제 형상을 촬영하고 구별하기 위한 광학카메라, 구성성분을 분석하기 위한 분광기, 지표에 노출되지 않은 시료를 얻기 위한 드릴로 이루어진 구성을 제안한다.

현대회화에서 드러난 해체의 형식론에 관한 연구 -타의적 해체와 자의적 해체의 성격규정을 중심으로- (A study of the destructive styles from Contemporary Paintings - Focused on distinguishing enmity-destruction and self-destruction -)

  • 박기웅
    • 조형예술학연구
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    • 제7권
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    • pp.5-63
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    • 2005
  • Generally, the meanings of destruction are related in the meaning of demolition, breakdown, into fragments ... and so on, and the similar meanings are twist, crush, demolish, split, cut, into pieces , break up ... etc. Further, it has related in the cruelty and destructive heart which are linked with orgy, Sadism, Necrophilia and so on. The meanings are also expressed by the initial , which are deprivation, deface, defame, deform, degrade, delegitimize, denounce , deride, destroy, devalue, as well as debase, debunk, declaim, declassify, decry, delete, denigrate, deprecate, despise or detract ...and so on. Dario Gamboni has discussed the meaning in his book as two categories Iconoclasm and Vandalism. And the similar meanings could be found in the words which has the initial of , like abase, abate, abhor, abjure, abolish, abridge, abuse ...and so on. Even though the distinct meanings of Iconoclasm and Vandalism, it is not easy to distinguish clearly between the differences when the results are accomplished in contemporary paintings because of the similarity of the results. In korean vocabulary there are no similar words to distinguish between the meanings of destruction and deconstruction, and the deconstruction is not recorded in the general dictionaries. However the meaning of is diminishing, separation, contrast and so on. So the unification of the word as do-construction is not construct, minus construction, reverse construction. And Vincent Ditch explained that there are the meaning of destroy the text. From Jacques Derrida, the deconstruction strategy is to criticise the world of traditional metaphysics and logocentrism, and not to reconstruire the philosophical meaning of texts but $d\'{e}construire$ them. And Saussure emphasized that the signifers could have more meaning that there can be more signified in traditional texts in the art. as a result, deconstruction is explained that there are many signified meanings in a signifer. In this thesis , from using the meanings of destruction and deconstruction, to distinguish the expressive skills in contemporary art works are arising. Therefore, special methods which are linked in the destruction styles are selected. As a result, the two different purposes of destruction is arising, one is enmity destruction and the other is self destruction another word, auto destruction or destruction to create The enmity destruction can be distinguished by the two category Iconoclasm and Vandalism. They come from the moment of different historical aspect is arising and want to attack the Icon or masterpiece this concept is from the study of John Philips and especially iconoclasm is linked with religious and artistic heart, but Vandalism is come from the political attack. Sometime, this distinguish is not clearly arising, because the two aspects are co-related in the attack. As a result, firstly, the Iconoclastic controversy had arisen in the methods of Dadaism which has developed by Man Ray, Francis Picabia and Marcel Duchamp. They want to attack the pre-established master-pieces and painting spaces, and they had 'non-artistic attitude' not to be art. Since 1980, the German artist Anselm Kiefer adapted the methods and made them his special skills so he had tried to paint tough brush strokes and draw with hugh pallette image line and fire and water images , they can be the image attack as the Iconoclasm. secondly, the model of vandalism is to be done by hammer, drill, canon and so on. the method is to attack the content of painting. Further, the object of destruction is bound by cords and iron lings to demolish or to declare the authority of pre-statues; it symbolize the pre-authority is gone already. Self-destruction based paintings are clearly different in the purpose of approaching the art work. First of all, they can be auto-destruction, creative destruction and metamorphosis destruction, which is linked with the skill the material aspect and basic stature, and sign destruction or signifier destruction, which is link with the inner meaning destruction that is considered as the Semiotical destruction in post-modern paintings. Since 1960, the auto destruction is based on the method of firing, melting, grinding and similar skills, which is linked with Neo-Dada and reverse-assemblage. Metamorphosis destruction is strongly linked with the basic inner heart price and quality, so it can be resulted in the changedness of expectation and recognition. Tony Cragg has developed the skills to metamorphose the wood as stone or iron as cloth and stone as sponge and rubber and so on. The researcher has developed the same style in the series of since 2003. The other self-destructive methods are found in the skill of sign destruction. In the methods the meaning of the art is not fixed as one or two, but is developed multi-meaning and differ from original starting situation, so Jacques Derrida called the difference meaning in deconstruction. It is the destruction of textes. These methods are accomplished by David Salle, Francesco Clemente, and recently Tracy Emin, who has developed the attacking heart in the spectators' emotion. Sometime in the method of self-destruction, it is based on horror and shock, the method is explored by Demian Hirst and Jakes and Dinos Chapman. Their destructive styles stimulate ambivalent heart and destroy original sign of girl and animals.

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