• Title/Summary/Keyword: triangular structure

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FINITE ELEMENT BASED FORMULATION OF THE LATTICE BOLTZMANN EQUATION

  • Jo, Jong-Chull;Roh, Kyung-Wan;Kwon, Young-W.
    • Nuclear Engineering and Technology
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    • v.41 no.5
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    • pp.649-654
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    • 2009
  • The finite element based lattice Boltzmann method (FELBM) has been developed to model complex fluid domain shapes, which is essential for studying fluid-structure interaction problems in commercial nuclear power systems, for example. The present study addresses a new finite element formulation of the lattice Boltzmann equation using a general weighted residual technique. Among the weighted residual formulations, the collocation method, Galerkin method, and method of moments are used for finite element based Lattice Boltzmann solutions. Different finite element geometries, such as triangular, quadrilateral, and general six-sided solids, were used in this work. Some examples using the FELBM are studied. The results were compared with both analytical and computational fluid dynamics solutions.

Nonlinear deflection responses of layered composite structure using uncertain fuzzified elastic properties

  • Patle, B.K.;Hirwani, Chetan K.;Panda, Subrata Kumar;Katariya, Pankaj V.;Dewangan, Hukum Chand;Sharma, Nitin
    • Steel and Composite Structures
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    • v.35 no.6
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    • pp.753-763
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    • 2020
  • In this article, the influence of fuzzified uncertain composite elastic properties on non-linear deformation behaviour of the composite structure is investigated under external mechanical loadings (uniform and sinusoidal distributed loading) including the different end boundaries. In this regard, the composite model has been derived considering the fuzzified elastic properties (through a triangular fuzzy function, α cut) and the large geometrical distortion (Green-Lagrange strain) in the framework of the higher-order mid-plane kinematics. The results are obtained using the fuzzified nonlinear finite element model via in-house developed computer code (MATLAB). Initially, the model accuracy has been established and explored later to show the dominating elastic parameter affect the deflection due to the inclusion of fuzzified properties by solving a set of new numerical examples.

Methodology for Performance_Based Evaluation of a RC Structure (철근콘크리트 구조물의 성능기반 평가방법)

  • Lee, Do-Hyung
    • The Journal of Engineering Research
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    • v.8 no.1
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    • pp.5-11
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    • 2006
  • In order to evaluate the seismic performance of a reinforced concrete building structure, four different analyses are carried out. Firstly, conventional pushover analysis with code-specified inverted triangular load pattern is conducted. Secondly, the pushover analysis with uniform load pattern is performed. Thirdly, adaptive pushover analyses with spectral amplification for both EC 8 artificial and Northridge earthquake are carried out. Lastly, Incremental dynamic analyses under a number of scaled PGA for both EC 8 artificial and Northridge earthquake record are performed. Comparative studies demonstrate that the adaptive pushover analysis may be able to explain the response characteristics that conventional pushover analysis with fixed load distribution fails to capture.

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Structural Design of Optimized Fuzzy Inference System Based on Particle Swarm Optimization (입자군집 최적화에 기초한 최적 퍼지추론 시스템의 구조설계)

  • Kim, Wook-Dong;Lee, Dong-Jin;Oh, Sung-Kwun
    • Proceedings of the IEEK Conference
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    • 2009.05a
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    • pp.384-386
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    • 2009
  • This paper introduces an effectively optimized Fuzzy model identification by means of complex and nonlinear system applying PSO algorithm. In other words, we use PSO(Particle Swarm Optimization) for identification of Fuzzy model structure and parameter. PSO is an algorithm that follows a collaborative population-based search model. Each particle of swarm flies around in a multidimensional search space looking for the optimal solution. Then, Particles adjust their position according to their own and their neighboring-particles experience. This paper identifies the premise part parameters and the consequence structures that have many effects on Fuzzy system based on PSO. In the premise parts of the rules, we use triangular. Finally we evaluate the Fuzzy model that is widely used in the standard model of gas data and sew data.

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Mirror Structure Analysis of High Resolution Optical Imaging Payload (고해상도 광학영상장비 반사경 구조해석)

  • Kwon, Woo-Gun;Kim, Kwang-Ro;Lee, Young-Shin
    • Proceedings of the KSME Conference
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    • 2003.04a
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    • pp.462-467
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    • 2003
  • For the Space-borne optical imaging payload system design, light weighting and moderate stiffness of mirror and/or mirror fixation device is very important aspects. The front surface of mirror is regulated by optical performance requirement, but the shape of backplate of mirror is to be optimised while satisfing the required stiffness and weight. According to the results, the best shape of backplate cell is triangular. And also related geometric dimensions and the optimised mounting point of MFD(Mirror Fixation Device) is presented. Finally, natural frequencies and shpaes of mirror structure are analysed.

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Telescopic columns as a new base isolation system for vibration control of high-rise buildings

  • Hosseini, Mahmood;Farsangi, Ehsan Noroozinejad
    • Earthquakes and Structures
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    • v.3 no.6
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    • pp.853-867
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    • 2012
  • In this paper, a new type of passive energy dissipating system similar to added damping and stiffness (ADAS) and triangular added damping and stiffness (TADAS) is proposed and implemented in the analytical model of a building with hybrid structural system in the structure's base which we call it; Telescopic column. The behavior and performance of a high rise R.C. structure equipped with this system is investigated and compared with conventional base isolation systems such as rubber isolator bearings and friction pendulum bearings. For this purpose a series of ground acceleration records of the San Fernando, Long Beach and Imperial Valley earthquakes are used as the disturbing ground motions in a series of numerical simulations. The nonlinear numerical modeling which includes both material and geometric nonlinearities were carried out by using SAP2000 program. Results show suitable behavior of structures equipped with telescopic columns in controlling the upper stories drifts and accelerations.

Structural Analysis of Plate Structures by Transfer of Stiffness Coefficient (강성계수의 전달에 의한 평판 구조물의 구조해석)

  • Choi, Myung-Soo
    • Journal of Power System Engineering
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    • v.11 no.1
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    • pp.92-97
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    • 2007
  • It is important to compute the structural analysis of plate structures in structural design. In this paper, the author uses the finite element-transfer stiffness coefficient method (FE-TSCM) for the structural analysis of plate structures. The FE-TSCM is based on the concept of the successive transmission of the transfer stiffness coefficient method and the modeling technique of the finite element method (FEM). The algorithm for in-plane structural analysis of a rectangular plate structure is formulated by using the FE-TSCM. In order to confirm the validity of the FE-TSCM for structural analysis of plate structures, two numerical examples for the in-plane structural analysis of a plate with triangular elements and the bending structural analysis of a plate with rectangular elements are computed. The results of the FE-TSCM are compared with those of the FEM on a personal computer.

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Two-Dimensional Photonic Bandgap Nanolasers (2차원 광밴드갭 나노레이저)

  • Lee, Y. H.;Hwang, J-K;H.Y. Ryu;Park, H. K.;D. J. Shin
    • Proceedings of the Optical Society of Korea Conference
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    • 2001.02a
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    • pp.2-3
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    • 2001
  • Characteristics of two-dimensional slab photonic crystal lasers will be summarized. Room temperature c.w operation is demonstrated at 1.6 $\mu\textrm{m}$ by using InGaAsP slab-waveguide triangular photonic crystal on top of wet-oxidized aluminum oxide. Recently, 2-D PBG structures have attracted a great deal of attention due to their simplicity in fabrication and theoretical study as compared to the three-dimensional counterparts [1]. Air-guided 2-D slab PBG lasers were reported by Caltech group (2). However, this air-slab structure is mechanically fragile and thermally unforgiving. Therefore, a new structure that can remove this thermal limitation is dearly sought after for 2-D PBG laser to have practical meaning. In this talk, we report room-temperature continuous operation of 2-D photonic bandgap lasers that are thermally and mechanically stable.(omitted)

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Safety Inspection Surveying using Change Detection Technique (Change Detection 기법을 이용한 구조물 안전진단측량)

  • Choi, Chul-Ung;Khak, Jae-Ha;Kang, In-Joon
    • Journal of Korean Society for Geospatial Information Science
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    • v.3 no.2 s.6
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    • pp.151-158
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    • 1995
  • Change detection, image differencing technique, is the most widely used in a variety of image environments. The digital terrain model and digital images have the same data structure. This study applied digital terrain model and change detection technique for inspecting the deflection of the structure. Authors make digital terrain model from triangular irregular network(TIN) by leveling data and suggest to possibility recognize modification part and volumes by digital terrain model and change detection technique. Authors can reduce testing materials and man power, and displayed his modification part.

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Optimal Design of Fuzzy Hybrid Multilayer Perceptron Structure (퍼지 하이브리드 다층 퍼셉트론구조의 최적설계)

  • Kim, Dong-Won;Park, Byoung-Jun;Oh, Sung-Kwun
    • Proceedings of the KIEE Conference
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    • 2000.07d
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    • pp.2977-2979
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    • 2000
  • A Fuzzy Hybrid-Multilayer Perceptron (FH-MLP) Structure is proposed in this paper. proposed FH-MLP is not a fixed architecture. that is to say. the number of layers and the number of nodes in each layer of FH-MLP can be generated to adapt to the changing environment. FH-MLP consists of two parts. one is fuzzy nodes which each node is operated as a small fuzzy system with fuzzy implication rules. and its fuzzy system operates with Gaussian or Triangular membership functions in premise part and constants or regression polynomial equation in consequence part. the other is polynomial nodes which several types of high-order polynomial such as linear. quadratic. and cubic form are used and is connected as various kinds of multi-variable inputs. To demonstrate the effectiveness of the proposed method. time series data for gas furnace process has been applied.

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