• Title/Summary/Keyword: Cross effects

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Dynamic Characteristics of Composite Thin-Walled Beams with a Chord wise Asymmetric Cross-Section: I. Single-Cell (시위 방향 비대칭 단면의 복합재료 박벽보의 동특성 연구: I. 단일-셀)

  • Kim, Keun-Taek
    • Journal of Aerospace System Engineering
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    • v.12 no.6
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    • pp.41-49
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    • 2018
  • In this study, the theoretical dynamic characteristics of a thin-walled composite beam with a single-cell of chordwise asymmetric cross-section was studied. Mathematical modeling was done by considering the transverse shear effects, the warping restraint effects, the constant taper ratio in the longitudinal direction of the beam, and the geometrical cross-section ratio. The mass coefficients, stiffness coefficients, and Eigen frequencies of the selected section were investigated. In particular, the effects of the taper ratio and cross-section ratio of the model on the Eigen frequencies were analyzed and compared when the asymmetry of the section was considered and the warping function was not corrected.

Analysis of cross-talk effects in volume holographic interconnections using perturbative integral expansion method

  • Jin, Sang-Kyu
    • Journal of the Optical Society of Korea
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    • v.2 no.2
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    • pp.58-63
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    • 1998
  • Cross-talk effects in high-density volume holographic interconnections are investigated using perturbative iteration method of the integral form of Maxwell's wave equation. In this method, the paraxial approximation and negligence of backward scattering introduced in conventional coupled mode theory is not assumed. Interaction geometries consisting of non-coplanar light waves and multiple index gratings are studied. Arbitrary light polarization is considered. Systematic analysis of cross-talk effects due to multiple index gratings is performed in increasing level of diffraction orders corresponding to successive iterations. Some numerical examples are given for first and third order diffraction.

A Design of Cross Effect Evaluation System for Estimating the Effectiveness of R&D Projects (R&D프로젝트군의 효과추정을 위한 복합효과 평가시스템의 설계)

  • 강일중;권철신;박준호
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2003.11a
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    • pp.21-24
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    • 2003
  • $\ulcorner$Cost Effectiveness Analysis$\lrcorner$ has been widely used to evaluate the effectiveness of R&D resources. But, almost of cost effectiveness evaluation systems have some problems, especially the cross effect among R&D projects has not been considered. To solve this problem, we have designed a new $\ulcorner$Cross Effect Evaluation System(CEES)$\lrcorner$, which are able to estimate multi-effects and cross effects by completion time among several projects.

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Analysis of rotational end restraint for cross-beams of railway through truss bridges

  • Siekierski, Wojciech
    • Steel and Composite Structures
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    • v.35 no.1
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    • pp.29-41
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    • 2020
  • Cross-beams of modern through truss bridges are connected to truss chord at its nodes and between them. It results in variable rotational end restraint for cross-beams, thus variable bending moment distribution. This feature is captured in three-dimensional modelling of through truss bridge structure. However, for preliminary design or rapid assessment of service load effects such technique of analysis may not be available. So an analytical method of assessment of rotational end restraint for cross-beam of through truss bridges was worked out. Two cases - nodal cross-beam and inter-nodal cross-beam - were analyzed. Flexural and torsional stiffness of truss members, flexural stiffness of deck members and axial stiffness of wind bracing members in the vicinity of the analyzed cross-beam were taken into account. The provision for reduced stiffness of the X-type wind bracing was made. Finally, general formula for assessment of rotational end restraint was given. Rotational end restraints for cross-beams of three railway through truss bridges were assessed basing on the analytical method and the finite element method (three-dimensional beam-element modelling). Results of both methods show good agreement. The analytical method is able to reflect effects of some structural irregularities. On the basis of the obtained results the general values of rotational end restraint for nodal and inter-nodal cross-beams of railway through truss bridges were suggested.

Effects of Cross-Head Speed And Probe Diameter on Instrumental Measurement of Tomato Firmness

  • Batu, Ali;Thompson, A.Keith
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1993.10a
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    • pp.1340-1345
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    • 1993
  • Five textural characteristics , epicarp strength, deformation , firmness , toughness and penetration time were calculated from force/deformation curves obtained by pressure testing tomato fruits. The fruits were harvested at either the mature-green or red maturity stages. The effects of changing the probe diameter and cross-head speed were investigated on force/deformation characteristics of tomatoes. It was confirmed that increasing of cross-head speed and probe diameter highly significantly effect all textural of the characteristics mentioned above , except epiarp strength of red tomatoes at 200 mm minute cross-head and penetration time of red and green tomatoes after 200mm minute and 100 mm minute cross-head respectively.

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A Study on the Cross-drilling Effects of Brake Disc Rotor (브레이크 디스크 로터 표면 수직 구멍의 영향에 관한 연구)

  • Seo, Young-Jin;Oh, Je-Ha;Lee, Jun-Sang;Kang, Kyoung-Soo;Jung, Geun-Sung
    • Transactions of the Korean Society of Automotive Engineers
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    • v.16 no.1
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    • pp.100-105
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    • 2008
  • Cross-drilling on the brake disc is generally known as a way of improving cooling efficiency. In other theories, cross-drilled holes act like a path of gas or water and are also known that they can reduce fading and wetting of brake rotors. However, in disc rotors with cross-drilling, thermal crack phenomena have been reported more frequently and more manufacturing cost should be paid than non cross-drilled disc rotors. In this study, to examine various effects of cross-drilling on the brake disc, two kinds of brake disc rotors, cross-drilled and non cross-drilled, were used in computational fluid dynamic analyses and dynamometer tests.

Mixed-effects LS-SVR for longitudinal dat

  • Cho, Dae-Hyeon
    • Journal of the Korean Data and Information Science Society
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    • v.21 no.2
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    • pp.363-369
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    • 2010
  • In this paper we propose a mixed-effects least squares support vector regression (LS-SVR) for longitudinal data. We add a random-effect term in the optimization function of LS-SVR to take random effects into LS-SVR for analyzing longitudinal data. We also present the model selection method that employs generalized cross validation function for choosing the hyper-parameters which affect the performance of the mixed-effects LS-SVR. A simulated example is provided to indicate the usefulness of mixed-effect method for analyzing longitudinal data.

End Effects of Thin-Walled Beams with General Quadrilateral Cross Sections (일반 사각 단면 형상을 갖는 박판보의 끝단효과에 관한 연구)

  • Kim, Jin-Hong;Kim, Yun-Yeong
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.24 no.9 s.180
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    • pp.2191-2201
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    • 2000
  • End effects due to sectional deformations of thin-walled beams with closed cross section are analysed by a one-dimensional theory. In particular, end effects associated with warping (out of plane m otion) and distortion (in plane motion) are investigated. The exact solutions as a vector form are newly derived to reveal slowly-decaying nature of the end effects in a thin-walled beam loaded by a couple. Several examples of thin-walled beams under various loading conditions indicate that the local end effect zone due to warping and distortion is approximately ten times the typical beam width.

Cross Correlated Effects of Radiation Damping and the Distant Dipolar Field with a Pulsed Field Gradient in Solution NMR

  • Chung Kee-Choo;Ahn Sang-Doo
    • Journal of the Korean Magnetic Resonance Society
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    • v.10 no.1
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    • pp.46-58
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    • 2006
  • With a simple pulse sequence ($\pi/2$-{gradient, duration T}-acquisition) in solution NMR, detected signal has slowly grown up to percents of the equilibrium magnetization. The source of this unusual resurrection of dephased magnetization after a crushed gradient is cross-correlated effects of radiation damping and the distant dipolar field, which has been demonstrated by a numerical simulation and theoretical analysis.

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