• 제목/요약/키워드: Shape of Lattice

검색결과 172건 처리시간 0.021초

격자지보의 터널지보재로서의 현장 적용성 평가 (Evaluation on the Applicability of a Lattice Girder for a Support System in Tunnelling)

    • 터널과지하공간
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    • 제9권3호
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    • pp.204-213
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    • 1999
  • 터널 굴착 방법 중 NATM에서는 숏크리트, 록볼트, 강지보재 등이 주요 지보재로 사용되고 있다. 강지보재 중에서 격자지보(Lattice Girder)라 불리는새로운 지보재가유럽에서 개발되어 기존의 H형강 지보재를 대체하여 사용되고 있다. 격자지보는 강봉을 삼각형태로 용접하여 만든 것으로 가벼워 시공이 빠르고, 또한 숏크리트와의 결합특성이 좋아 앞으로 NATM 터널에 널리 사용될 전망이다. 본 연구에서는 국내 터널에 있어서 격자지보의 현장 적용성을 평가하기 위하여 대단면 고속철도 터널에서 현장시험시공을 실시하였으며, 기존의 H형강 지보재와 비교분석 하였다. 현장시험 결과 격자지보는 터널굴착 후의 지반하중을 충분히 지지할 수 있으며 지반변위를 효과적으로 억제할 수 있음을 알 수 있었다.

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An NMR Study of Unequal Site Exchange of 9-Methyl Group in Triptycene by Spin-Lattice Relaxation and 2D-EXSY Experiments

  • Cho, Jang-Geun;Ahn, Sang-Doo
    • 한국자기공명학회논문지
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    • 제11권1호
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    • pp.1-9
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    • 2007
  • An unequal site exchanging system induced by restricted rotation of 9-methyl group in 1,8-dichloro-9-triptycene has been studied by spin-lattice relaxation and 2D-EXSY experiments. The exchange rate obtained from relaxation studies is very well coincident to the result of line shape analysis, and the difference of the relaxation times ($T_1$) in two different sites has an important role to analyze 2D-EXSY experimental data.

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삼각 격자구조를 갖는 평면배열 안테나의 부엽 레벨 감소를 위한 최적 평면배열 형상에 관한 연구 (STUDY ON THE OPTIMAL PLANAR ARRAY STRUCTURE WITH TRIANGULAR LATTICE FOR SIDE-LOBE REDUCTION)

  • 배지훈;성낙선;이태윤;김종면;표철식
    • 한국전자파학회:학술대회논문집
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    • 한국전자파학회 2002년도 종합학술발표회 논문집 Vol.12 No.1
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    • pp.250-254
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    • 2002
  • In this paper, we design an optimized planar array structure with triangular lattice for side-lobe reduction using a genetic algorithm. A constraint optimization is implemented by optimally removing some outer array elements far from the array center. It is shown that only the proper array shape without optimizing the magnitudes and phases of each array antenna can give low side-lobe level with a slight main beam broadening.

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PbTe 열전재료에 형성된 HgTe 나노개제물의 석출거동: 초기 격자 불일치의 형성, 이론적 계산 및 실험적 증명 (Precipitation Behaviors of HgTe Nanoinclusions Formed in Thermoelectric PbTe: Initial Induced Lattice Mismatch, Theoretical Calculation and Experimental Verification)

  • 김경호;권태형;박수한;안형근;이만종
    • 한국전기전자재료학회논문지
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    • 제24권7호
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    • pp.599-604
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    • 2011
  • A highly strained nanostructure comprising crystallographically aligned HgTe nanoinclusions and a surrounding PbTe matrix has been synthesized using a precipitation process of supersaturated HgTe-PbTe alloys. From the early precipitation stage, HgTe nanoinclusions take disk shape, which is transformed from initial HgTe nuclei, although there is no lattice constant difference of the two end components at standard state. As a primary reason for the morphological transformation of the initial spherical HgTe nuclei to HgTe nanodisks, the induced lattice mismatch is suggested. On the condition that the HgTe nanodisks maintain perfect coherent nature with PbTe matrix, the stress-free lattice constant of constrained HgTe nanodisks has been calculated based on the defined concept of the strain-induced tetragonality, the linear elasticity and the actual measurement in HRTEM images.

미세 격자가 형성된 배양 접시를 이용한 새로운 세포 계수 방법 (A Novel Cell Count Method Using Micro Lattice Engraved On A Culture Dish)

  • 손상욱;최요한;이승섭
    • 대한기계학회논문집A
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    • 제28권8호
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    • pp.1183-1189
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    • 2004
  • A novel cell count method, which can improve the count efficiency and reduce contamination problem, was presented using micro lattice engraved on culture dish. The micro lattice has feature of $50{\mu}m{\times}50{\mu}m$ rectangular shape, $2{\mu}m$ line width, and $2{\mu}m$ depth in $3mm{\times}3mm$ area. In this paper, nickel mold was fabricated with thickness of 3mm and diameter of 80 mm, and transcription of the micro lattice on a polystyrene cell culture dish was performed by hot embossing at $200\;^{\circ}C$. The tedious and error-prone harvest/load processes of conventional cell counts with a hemocytometer could be omitted, and these advantages became magnified during periodical counts involving long-term cultures. SupT1 cells and HeLa cells were cultivated with the dish for 7 days in $CO_2$ incubator and counted as $371.84/mm^2$ and $123.36/mm^2$, respectively, during the cultivation without harmful effects on the cells.

Theoretical Consideration on Influences of Cavity or Pillar Shape on Band Structures of Silicon-Based Photonic Crystals

  • Ogawa, Yoshifumi;Tamura, Issei;Omura, Yasuhisa;Iida, Yukio
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제7권1호
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    • pp.56-65
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    • 2007
  • This paper describes physical meanings of various influences of cavity (or pillar) shape and filling factor of dielectric material on band structures in two-dimensional photonic crystals. Influences of circular and rectangular cross-sections of cavity (or pillar) arrays on photonic band structures are considered theoretically, and significant aspects of square and triangular lattices are compared. It is shown that both averaged dielectric constant of the photonic crystal and distribution profile of photon energy play important roles in designing optical properties. For the triangular lattice, especially, it is shown that cavity array with a rectangular cross-section breaks the band structure symmetry. So, we discuss this point from the band structure and address optical properties of lattice with a circular cross-section cavity.

Practical optimization of power transmission towers using the RBF-based ABC algorithm

  • Taheri, Faezeh;Ghasemi, Mohammad Reza;Dizangian, Babak
    • Structural Engineering and Mechanics
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    • 제73권4호
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    • pp.463-479
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    • 2020
  • This paper is aimed to address a simultaneous optimization of the size, shape, and topology of steel lattice towers through a combination of the radial basis function (RBF) neural networks and the artificial bee colony (ABC) metaheuristic algorithm to reduce the computational time because mere metaheuristic optimization algorithms require much time for calculations. To verify the results, use has been made of the CIGRE Tower and a 132 kV transmission towers as numerical examples both based on the design requirements of the ASCE10-97, and the size, shape, and topology have been optimized (in both cases) once by the RBF neural network and once by the MSTOWER analyzer. A comparison of the results shows that the neural network-based method has been able to yield acceptable results through much less computational time.

한국적 디자인을 기본으로 한 패션문화상품 조끼디자인 개발 - 전통 창살문양 응용 - (Vest Design Development of Fashion Culture Products based on Korean Style - Application of Traditional Lattice Pattern of Doors -)

  • 최은주
    • 한국의류산업학회지
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    • 제21권4호
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    • pp.412-419
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    • 2019
  • This study is to help maintain the identity of traditional Korean culture and develop fashion culture products by applying images and composition forms of traditional lattice patterns for vest designs. Lattice can be distinguished as a shape created through intersecting vertical and horizontal lines, in the form of oblique lines in vertical and horizontal structures, and in the form of an oblique line. Lattice patterns represent the overall unity and order as well as the beauty of small spaces created by simple lines. Traditional lattice patterns of the Joseon Dynasty were examined theoretically through the literature. Based on theoretical grounds, there is study illustrates vest designs using Adobe Illustrator CS6 as well as works on a 3D virtual costume using CLO Trial 4.2, a 3D virtual dressing system of CLO Virtual Fashion. This study developed an easy to wear vest design categorized as clothes for both men and women. The geometric formality of the lattice pattern has been applied to fashion culture products. In this study, the design was developed focusing on lattice, kotsal (flower pattern), sosulbitsal (diagonal), sotdaesal, tisal (horizontal & vertical). This study can be used as basic data in the domestic fashion cultural product market that can help maintain the originality of Korean culture in the global era that also assists in the successful promotion of Korean culture and traditions.

2 차원 광결정의 실공간 밴드구조 계산 (A Real-Space Band-Structure Calculation of 2D Photonic Crystals)

  • 전석기;조영삼;임세영
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.1089-1093
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    • 2003
  • The moving least square (MLS) basis is implemented for the real-space band-structure calculation of 2D photonic crystals. The value-periodic MLS shape function is thus used in order to represent the periodicity of crystal lattice. Any periodic function can properly be reproduced using this shape function. Matrix eigenequations, derived from the macroscopic Maxwell equations, are then solved to obtain photonic band structures. Through numerical examples of several lattice structures, the MLS-based method is proved to be a promising scheme for predicting band gaps of photonic crystals.

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비선형 와류격자법을 이용한 낮은 종횡비 날개의 공력특성 계산 (Calculation of Low Aspect Ratio Wing Aerodynamics by Using Nonlinear Vortex Lattice Method)

  • 이태승;박승오
    • 한국항공우주학회지
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    • 제36권11호
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    • pp.1039-1048
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    • 2008
  • 본 논문에서는 새로운 비선형 와류격자법 계산 과정이 제안된다. 기존의 계산 과정은 자유와의 형태 계산을 위해 내부 반복계산 및 하향이완법을 포함한다. 하지만 본 논문에서는 유사 정상 개념에 기초한 새로운 수식을 제안하여 자유와의 형태를 계산함으로써, 계산 과정에서 내부 반복계산 및 하향이완법을 생략한다. 또한 반복계산이 진행됨에 따라 각 분절에 유도되는 유속도를 적절히 평균해 줌으로써 알고리듬의 수치적 안정성을 향상시킨다. 그리고 낮은 종횡비 날개에 대한 수치실험을 수행하여 분절의 길이, 와류중심반경, 후류영역 계산범위 등과 같은 중요 인자들의 적절한 기준을 경험적으로 결정한다.