• Title/Summary/Keyword: Selective Integration

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Higher Order Quadrilateral Plate Bending Finite Element (고차(高次) 판(板) 사각형(四角形) 유한요소(有限要素))

  • Shin, Young Shik;Shin, Hyun Mook;Kim, Myung Chul
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.8 no.2
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    • pp.25-32
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    • 1988
  • A formulation of an isoparametric quadrilateral higher-order plate bending finite element is presented. The 8-noded 28-d.o.f. plate element has been degenerated from the three-dimensional continuum by introducing the plate assumptions and considering higher-order in-plane displacement profile. The element characteristics have been derived by the Galerkin's weighted residual method and computed by using the selective reduced integration technique to avoid shear-locking phenomenon. Several numerical examples are given to demonstrate the accuracy and versatility of the proposed quadrilateral higher-order plate bending element over the other existing plate finite elements in both static and dynamic analyses.

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Evaluation on the Selective Combining for the Detection of M-ary DPSK Signals over Nakagami Fading Channels

  • Na, Seung-Gwan;Kim, Chang-Hwan;Jin, Yong-Ok
    • Journal of electromagnetic engineering and science
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    • v.7 no.2
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    • pp.74-82
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    • 2007
  • The performances of M-ary DPSK(MDPSK) for diversity reception theoretically are derived, using an L-branch selection combining(SC) in frequency-nonselective slow Nakagami fading channels. For integer values of the Nakagami fading parameter m, An exact closed-form symbol error rate(SER) multichannel performance that can be easily evaluated via numerical integration is presented. Finally, we compare these analyses with numerical analyses with integral-form expressions for the performance of MDPSK signals under the effect of two-branch SC diversity over slow and nonselective Rician fading channels with additive white Gaussian noise(AWGN).

A 4-Node Non-conforming Flat Shell Element with Drilling DOF (면내회전자유도를 가지는 4절점 비적합 평면쉘의 개발)

  • 최창근;이필승
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1998.10a
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    • pp.27-34
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    • 1998
  • A versatile flat shell element has been developed by combining a membrane element with drilling degree-of-freedom and a plate bending element. This element is formulated by the enhanced displacement field with the additional non-conforming displacement modes. Thus the element possesses six degrees-of-freedom (DOF) per node which permits an easy connection to other six DOF elements as well as the improvement of the element behavior. In plate bending part, this element is established by the combined use of the addition of non-conforming modes, the reduced (or selective) integration scheme, and the construction of the substitute shear strain fields. The achieved improvement may be attributable to the fact that the merits of these individual techniques are merged into the new element in a complementary manner. In membrane part, this element shows better membrane behavior as the nonconforming displacement mode is added to drilling mode.

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Adaptive finite element wind analysis with mesh refinement and recovery (요소 세분화 및 재결합을 이용한 바람의 적응적 유한요소 해석)

  • 최창근;유원진;이은진
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1998.04a
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    • pp.60-67
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    • 1998
  • This paper deals with the development of a variable-node element and its application to the adaptive h-version mesh refinement-recovery for the incompressible viscous flow analysis. The element which has variable mid-side nodes can be used in generating the transition zone between the refined and unrefined elements and efficiently used for construction of a refined mesh without generating distorted elements. A modified Gaussian quadrature is needed to evaluate the element matrices due to the discontinuity of derivatives of the shape functions used for the element. The penalty function method which can reduce the number of independent variables is adopted for the purpose of computational efficiency and the selective reduced integration is carried out for the convection and pressure terms to preserve the stability of solution. For the economical analysis of transient problems, not only the mesh refinement but also the mesh recovery is needed. The numerical examples show that the optimal mesh for the finite element analysis of a wind around the structures can be obtained automatically by the proposed scheme.

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Stereoscopic Millimeter-wave Image Processing for Depth Information

  • Park, Min-Chul;Son, Jung-Young
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.1022-1024
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    • 2009
  • Stereoscopic Images provide depth information with the relative distances between the objects in the images. There are many different ways to extract disparity maps from the visible spectral images. For the infrared spectral range, the same approach cannot be utilized for the innate low resolution and colorless features because typical methods require corresponding features between the images. The authors suggest a new approach that makes use of image segmentation to obtain depth information for stereoscopic millimeter-wave images. For image segmentation a selective visual attention model based on the theory of a feature-integration of attention is used. Experimental results show the proposed method provides reasonable depth information for object shape recognition and display.

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A robust nonlinear mathematical programming model for design of laterally loaded orthotropic steel plates

  • Maaly, H.;Mahmoud, F.F.;Ishac, I.I.
    • Structural Engineering and Mechanics
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    • v.14 no.2
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    • pp.223-236
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    • 2002
  • The main objective of the present paper is to address a formal procedure for orthotropic steel plates design. The theme of the proposed approach is to recast the design procedure into a mathematical programming model. The objective function to be optimized is the total weight of the structure. The total weight is function of its layout parameters and structural element design variables. Mean while the proposed approach takes into consideration the strength and rigidity criteria in addition to other dimensional constraints. A nonlinear programming model is developed which consists of a nonlinear objective function and a set of implicit/explicit nonlinear constraints. A transformation method is adopted for minimization strategy, where the primal model constrained problem is transformed into a sequence of unconstrained minimization models. The search strategy is based on the well-known Fletcher/Powell algorithm. The finite element technique is adopted for discretization and analysis strategies. Mindlin theory is selected to simulate the finite element model and a selective reduced integration scheme is exploited to avoid a shear lock problem.

Nonlinear Analysis of Shell Structures by Improved Degenerated Shell Element (개선된 degenerated 쉘요소를 사용한 쉘구조의 비선형해석)

  • 최창근;유승운
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1990.04a
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    • pp.18-23
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    • 1990
  • The paper is concerned with the elasto-plastic and geometrically nonlinear analysis of shell structures using an improved degenerated shell element. In the formulation of the improved degenerated shell element, an enhanced interpolation of transverse shear strains in the natural coordinate system is used to overcome the shear locking problems; the reduced integration technique in in-plane strains is applied to avoid membrane locking behavior; selective addition the nonconforming displacement modes improve the element performances. This element is free of serious locking problems and undesirable compatible or commutable spurious kinematic deformation modes and passes the patch tests. An incremental total Lagrangian formulation is presented which allows the calculation of arbitrarily large displacements and rotations. The resulting nonlinear equations are solved by the Newton-Raphson solution scheme. The versatility and accuracy of this improved degenerated shell element are demonstrated by solving several numerical examples.

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In vivo Trafficking of Liposomes Containing Boron Compounds for Boron Neutron Capture Therapy (BNCT)

  • Huu Bao Nguyen;Jeongsoo Yoo
    • Journal of Radiopharmaceuticals and Molecular Probes
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    • v.9 no.1
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    • pp.43-48
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    • 2023
  • For over 50 years, boron neutron capture therapy (BNCT) has been steadily developed for treating various cancers. This is a non-invasive, selective, and targeted radiotherapy wherein boron-rich molecules accumulate at the tumor site. Liposomal vesicles have become a popular and effective drug delivery system for BNCT, with strategies including surface decoration, bilayer integration, and hydrophilic core encapsulation. This review highlights the state-of-the-art uses of liposomes in BNCT and elucidates a new perspective where BNCT can be used with radiotracer guidance in all-in-one delivery systems.

A CMOS Fully Integrated Wideband Tuning System for Satellite Receivers (위성 수신기용 광대역 튜너 시스템의 CMOS 단일칩화에 관한 연구)

  • Kim, Jae-Wan;Ryu, Sang-Ha;Suh, Bum-Soo;Kim, Sung-Nam;Kim, Chang-Bong;Kim, Soo-Won
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.39 no.7
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    • pp.7-15
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    • 2002
  • The digital DBS tuner is designed and implemented in a CMOS process using a direct-conversion architecture that offers a high degree of integration. To generate mathched LO I/Q quadrature signals covering the total input frequency range, a fully integrated ring oscillator is employed. And, to decrease a high level of phase noise of the ring oscillator, a frequency synthesizer is designed using a double loop strucure. This paper proposes and verifies a band selective loop for fast frequency switching time of the double loop frequency synthesizer. The down-conversion mixer with source follower input stages is used for low voltage operation. An experiment implementation of the frequency synthesizer and mixer with integrated a 0.25um CMOS process achieves a switching time of 600us when frequency changes from 950 to 2150MHz. And, the experiment results show a quadrature amplitude mismatch of max. 0.06dB and a quadrature phase mismathc of max. >$3.4^{\circ}$.

The Migrant Women Policy in Korea : Prospect and Implication in the point of Interculturalism (한국의 여성 결혼이주자정책 : 상호문화주의적 조망과 함의)

  • Kim, Kyung Sook
    • Journal of Digital Convergence
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    • v.12 no.9
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    • pp.21-33
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    • 2014
  • This is a research on the characteristic and its limit of Korean migrant women policy to prospect and suggest in the point of interculturalism. The focus of this paper is in summing-up to current situation of multiethnic society which rapidly progressing in Korea and in reviewing the race-oriented, gender-biased issue in the migrant women policy in Korea. However, the migrant women go through by the unique rebuilt progress in the transnational social field which can be continue for several or for decades between delivery country and inflow country but the one-sided, certain movement to a new country. In the above mentioned standpoint, this paper can suggest the implication for the concept and its character of interculturalism, the policy and undertasking case in Europe as a realistic directing point on which the migrant women policy in Korea. The educational program consolidation of intercultural citizenship, the orientation of pluralistic integration through selective assimilation, the consolidation of intercultural adaptation program, the intercultural measurement metrics development and feedback which considered of Korean characteristics are proposed in this paper.