• 제목/요약/키워드: four-dimensional

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임플란트 지지 하악 캔틸레버 보철물의 디자인에 따른 저작압 분산에 관한 삼차원 유한요소 분석 (Three-dimensional finite element analysis on stress distribution of the mandibular implant-supported cantilever prostheses depending on the designs)

  • 반재혁;신상완;김선종;이정열
    • 대한치과보철학회지
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    • 제47권1호
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    • pp.70-81
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    • 2009
  • 연구목적: 캔틸레버의 위치와 길이는 임플란트와 보철물 또한 주위 골조직의 응력분포에 중요한 영향을 미친다. 하악 무치악의 경우 기존에는 양측 이공사이에 4-6개의 임플란트를 식립하고 상부보철물을 캔틸레버형으로 제작해왔는데 캔틸레버 부위에 무리한 하중이 작용하게 되면 응력의 집중과 굽힘 현상으로 인하여 최후방 임플란트 부위의 지지골 파괴와 임플란트 및 상부 보철물의 파절을 초래했다. 이러한 캔틸레버의 약점을 보완하기 위해 1992년 McCartney가 Rest implant 개념을 2003년에는 $Mal{\acute{o}}$ 등이 All-on-Four implant 개념을 소개하여 기존 보철물의 캔틸레버 길이를 줄이려고 노력하였다. 재료 및 방법: 기존의 캔틸레버형 보철물과 rest implant, All-on-Four implant 시스템을 삼차원 모델링하여 하중을 제 1대구치 부위에 수직으로 300 N, 수평으로 설측에서 협측으로 75 N을 가하여 지지골과 임플란트, 상부보철물에 발생하는 응력의 크기와 분포 및 분산양상을 유한요소 해석 프로그램인 ANSYS (Ver. 10.0, Swanson Analysis System Inc., USA)를 이용하여 분석하였다. 결과: 1. 레스트 임플란트 및 All-on-Four 임플란트법은 기존 방법에 비해 하악골과 상부 보철물의 응력 분산에 크게 영향을 미치는 것으로 나타났다. 2. 지지골, 임플란트, 상부 보철물에서의 응력분산은 레스트 임플란트가 가장 우수한 것으로 나타났다. 3. 같은 개수의 임플란트인 경우 후방 임플란트를 경사시켜 캔틸레버의 양을 줄이는 것이 기존 방식에 비해 저작압 분산에 유리하다.

Time Delay Control of Sway and Skew of the Spreader Suspended by Four Flexible Cables

  • Lee, Jeong-Woo;Kim, Doo-Hyeong;Park, Kyeong-Taik
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2004년도 ICCAS
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    • pp.540-545
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    • 2004
  • This article describes the time delay control of the 3-dimensional motion of the container cranes used in dockside container terminals. The container is suspended by four flexible cables via spreader, and due to the disturbances such as the wind and acceleration of cranes, the container undergoes translational(sway) and rotational position errors. And due to the uncertainty of weight and rotational inertia, accurate position control of container crane is difficult to realize. This paper, based on the analysis of 3-dimensional dynamics of container moving systems, develops time delay control algorithm [1]. The developed control algorithm is shown effective in controlling the container position in the presence of gust and parameter uncertainties.

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감과실을 첨가한 고추장의 관능적 특성 최적화 (Optimization on Organoleptic Properties of Kochujang with Addition of Persimmon Fruits)

  • 이기동;정용진
    • 한국식품영양과학회지
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    • 제27권6호
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    • pp.1132-1136
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    • 1998
  • The optimum mixing conditions of kochujang(persimmon kochujang) added persimmon puree was optimized by four dimensional response surface methodology. The organoleptic color of persimmon kochujang showed the maximum score in 86.74g red pepper powder, 133.51g persimmon puree and 26.31g salt. The organoleptic aroma persimmon kochujang showed the maximum score in 83.48g red pepper powder, 135.38g persimmon puree and 24.50g salt. The organoleptic taste of persimmon ko chujang showed the maximum score in 85.09g red pepper powder, 133.61g persimmon puree and 25.57g salt. The overall palatability of persimmon kochujang showed the maximum score in 82.99g red pepper powder, 133.10g persimmon puree and 25.47g salt. The optimum mixing conditions for overall orga noleptic properties of persimmon kochujang were 83.00g red pepper powder, 133.00g persimmon puree and 25.00g salt.

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VFH(Vector Field Histogram)을 이용한 4족 로봇의 장애물 회피 (Obstacle a voidance using VFH (Vector Field Histogram) in four legged robot)

  • 정현룡;김영배
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 학술회의 논문집 정보 및 제어부문 A
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    • pp.23-26
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    • 2003
  • The vector field histogram(VFH) uses a two-dimensional Cartesian histogram grid as a world model. The VFH method subsequently employs a two-stage data-reduction process in order to compute the desired control commands for the vehicle. In the first stage the histogram grid is reduced to a one dimensional polar histogram that is constructed around the robot's momentary location. Each sector in the polar histogram contains a value representing the polar obstacle density in that direction. In the second stage, the algorithm selects the most suitable sector from among all polar histogram sectors with a low polar obstacle density, and the steering of the robot is aligned with that direction. We applied this algorithm to our four-legged robot.

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Fuzzy Control of a Sway and Skew of a Spreader by Using Four Auxiliary Cables

  • Lee, Jeong-Woo;Kim, Doo-Hyeong;Park, Kyeong-Taik
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2005년도 ICCAS
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    • pp.1723-1728
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    • 2005
  • This article describes the fuzzy control of the 3-dimensional motion of the container cranes used in dockside container terminals. The container is suspended by four flexible cables via spreader, and due to the disturbances such as the wind and acceleration of cranes, the container undergoes translational(sway) and rotational position errors. And due to the uncertainty of weight and rotational inertia, accurate position control of container crane is difficult to realize. This paper, based on the analysis of 3-dimensional dynamics of container moving systems, describes the design of the fuzzy controller, which does not require the computation time to optimize the distribution of cable tension. The developed controller is shown effective in controlling the container position in the presence of gust and parameter uncertainties.

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Stresses analyses of shell structure with large holes

  • Tian, Zongshu;Liu, Jinsong
    • Structural Engineering and Mechanics
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    • 제6권8호
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    • pp.883-899
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    • 1998
  • The strength, deformation and buckling of a large engineering structure consisting of four ellipsoidal shells, two cylindrical shells with stiffening ribs and large holes, one conical shell and three pairs of large flanges under external pressure, self weight and heat sinks have been analysed by using two kinds of five different finite elements - four assumed displacement finite elements (shell element with curved surfaces, axisymmetric conical shell element with variable thickness, three dimensional eccentric beam element, axisymmetric solid revolutionary element) and an assumed stress hybrid element (a 3-dimensional special element developed by authors). The compatibility between different elements is enforced. The strength analyses of the top cover and the main vessel are described in the paper.

느타리버섯 통조림 제조에 있어서 관능적 특성의 최적화 (Optimization of Sensory Properties in Preparation of Canned Oyster Mushroom)

  • 이기동;권중호;김진구;김현구
    • 한국식품영양과학회지
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    • 제26권3호
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    • pp.443-449
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    • 1997
  • Four-dimensional response surface methodology was applied to determine the optimum preparation conditions and to monitor sensory qualities of canned oyster mushroom during preparation. The optimum preparation conditions predicted for each corresponding sensory parameter of canned oyster mushroom were 181.29 g of oyster mushroom 205.36 ml of solution and 6.49min of roasting time for color, 214.01g, 195.79ml and 5.07min for appearance, 227.71g, 224.26ml and 6.50min for flavor, 250.30g, 183.63ml and 17.32min for taste, 211.59g, 178.21ml and 17.79min for mouth-feel, 249,.02g, 188.79ml and 17.80min for overall palatability of canned oyster mushroom, respectively. The optimum conditions, which satisfied with all sensory properties of canned oyster mushroom, were 240g, 200ml and 17min for content of oyster mushroom, content of solution and roasting time, respectively. Sensory scored predicted at the optimum conditions were in good agreement with experimental ones.

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회전-리니어 병용 유도전동기의 특성해석 (Optimal Construction of Rotary-Linear Induction Motor)

  • 오누끼 다까시;전우진;다나비끼 마사모토;유지윤
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1997년도 하계학술대회 논문집 A
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    • pp.130-132
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    • 1997
  • In this paper, we propose a new type of tubular linear induction motor(TLIM) with two-dimensional motion. The proposed motor consists of four short primary LIMs arranged on a same circumference and a common secondary. By adopting independently energized ring-windings to the primary, we can expect the reduction of coil-end region and the freedom of alternating current supply. The secondary conductor is capable of producing anyone of rotary, linear, and helical motions by controlling the phase of supply currents in each primary winding. From the 3-D finite element analysis and the experiment, we derive the feeding conditions to increase the subsidiary rotary-force and an optimal arrangement of primary currents to reduce the number of slot.

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감식초 및 감고추장을 이용한 감초고추장의 최적 배합비 설정 (Extablishment of Optimum Recipe on Persimmon Chokochujang using Persimmon Vinegar and Kochujang)

  • 이기동;정용진;서지형;이명희
    • 동아시아식생활학회지
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    • 제8권3호
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    • pp.309-315
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    • 1998
  • The optimum recipe of persimmon chokochujang using persimmon vinegar and kochujang was established by four-dimensional response surface methodology. The organoleptic color of persimmon chokochujang showed maximum score in 18.16g of persimmon vinegar, 5.58g of garlic and 1.62 g of sucrose. The organoleptic aroma of persimmon chokochujang showed macimum score in 18.19g of persimmon vinegar, 4.57g of garlic and 2.06g of sucrose. The organoleptic taste of persimmon chokochujang showed maximum score in 19.28g of persimmon vinegar, 4.97g of garlic and 2.34g of sucrose. The organoleptic color of persimmon chokochujang showed maximum score in 18.81g of persimmon vinegar, 4.81g of garlic and 2.65g of sucrose. Optimum mixing ranges for organoleptic properties of persimmon chokkochujang were 18.25~19.25g of persimmon vinegar, 4.60~5.00g of garlic and 2.06~2.65g of sucrose.

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2차원 밀폐 캐비티의 고레이놀즈수 흐름에 관한 연구 (A Study on High Reynolds Number Flow in Two-Dimensional Closed Cavity)

  • 최민선;송치성;이영호
    • Journal of Advanced Marine Engineering and Technology
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    • 제20권3호
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    • pp.101-109
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    • 1996
  • Two-dimensional lid-driven closed flows within square cavity were studied numerically for four Reynolds numbers : $10^4$, 3$\times10^4$, 5$\times10^4$ and 7.5$\times10^4$. A convective difference scheme to maintain the same spatial accurary by irregular grid correction is adopted by applying the interior division principle. Grid number is $80\times80$and its minimum size is about 1/400 of the cavity height. At Re=$10^4$, periodic migration of small eddies appearing in corner separation region and its temporal sinusoidal fluctuation are represented. At three higher Reynolds numbers(3$\times10^4$, 5$\times10^4$ and 7.5$\times10^4$), an organizing structure of four consecutive vorticles at two lower corners is revealed from time-mean flow patterns. But, instantaneous flow characteristics show very random unsteady fluctuation mainly due to the interaction between rotating shed vortices and stationary eddies within the corners.

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