• Title/Summary/Keyword: Quasi-dimensional

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Three-dimensional heat transfer analysis of laser cutting process for CSP 1N sheet using high power CW Nd:YAG laser (고출력 CW Nd:YAG 레이저를 이용한 CSP 1N 냉연강판 절단 공정의 3 차원 열전달 해석)

  • Kim M.S.;Ahn D.G.;Lee S.H.;Yoo Y.T.;Park H.J.;Shin H.J.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.10a
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    • pp.162-165
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    • 2005
  • The objective of this research work is to investigate into the three-dimensional temperature distribution using quasi steady-state heat transfer analysis fur the case of the laser cutting of CSP 1N sheet using high power CW Nd:YAG laser. The laser heat source is assumed as a volumetric heat source with a gaussian heat distribution in a plane. Through the comparison of the results of analyses with those of the experiments, the optimal finite element model is obtained. Finally, characteristics of the three-dimensional heat transfer and temperature distribution have been estimated by the optimal finite element model.

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EIGENVALUE APPROACH FOR UNSTEADY FRICTION WATER HAMMER MODEL

  • Jung Bong Seog;Karney Bryan W.
    • Water Engineering Research
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    • v.5 no.4
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    • pp.177-183
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    • 2004
  • This paper introduces an eigenvalue method of transforming the hyperbolic partial differential equations of a particular unsteady friction water hammer model into characteristic form. This method is based on the solution of the corresponding one-dimensional Riemann problem that transforms hyperbolic quasi-linear equations into ordinary differential equations along the characteristic directions, which in this case arises as the eigenvalues of the system. A mathematical justification and generalization of the eigenvalues method is provided and this approach is compared to the traditional characteristic method.

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Analysis of a Queueing System with Two Types of Arrival Patterns (두 종류의 도착형태를 갖는 대기행렬 체계의 분석)

  • Lee, Hwa-Gi;Yun, Eun-Sang
    • Journal of Korean Institute of Industrial Engineers
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    • v.14 no.1
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    • pp.17-30
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    • 1988
  • The aim of this project is to analyze the queueing model with the two types of customers which either can wait unrestrictedly or wait restrictively in the system depending on the condition of service facility unless they may be served immediately. This model consists of the three-dimensional state space and then quasi birth-death process is formulated. The steady-state probabilities and measures of performance of this system are derived by using Matrix Geometric method.

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On Conformally at Almost Pseudo Ricci Symmetric Mani-folds

  • De, Uday Chand;Gazi, Abul Kalam
    • Kyungpook Mathematical Journal
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    • v.49 no.3
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    • pp.507-520
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    • 2009
  • The object of the present paper is to study conformally at almost pseudo Ricci symmetric manifolds. The existence of a conformally at almost pseudo Ricci symmetric manifold with non-zero and non-constant scalar curvature is shown by a non-trivial example. We also show the existence of an n-dimensional non-conformally at almost pseudo Ricci symmetric manifold with vanishing scalar curvature.

Numerical Study on the Thermal Model of High Power Density Welding (고에너지 밀도용접의 온도특성에 관한 수치해석적 연구)

  • 이성호;고상근
    • Journal of Welding and Joining
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    • v.10 no.2
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    • pp.19-31
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    • 1992
  • A numerical study was performed to investigate the flow field and the heat transfer characteristics occurring in high power density welding which is important in many fields of engineering applications. A two dimensional quasi-steady state of keyhole welding model is simulated by using the finite volume methods. It is shown that the shape of isothermal line is elliptic and the temperature gradient is very steep compared with other welding method and the welding speed has on welding width and observed beam power.

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Analysis of Transmission-line Discontinuities by 3-dimensional Finite Element Method (3차원 유한요소법에 의한 도파로의 불연속 특성 해석)

  • 이상수;안창회;정봉식;이수영
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.28A no.5
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    • pp.355-360
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    • 1991
  • A transmission-line discontinuities are analyzed by Finite Element Method. We use quasi-static approxmation to determine the circuit parameters of discontinuities. Delta formulation is introduced so that the cancellation error of potential calculation is reduced. To verify this method, capacitance of coaxial cable with discontinuous and coupling capacitances are calculated by modal expansion. This approach can be used for arbitrary discontinuous conducting patterns of microwave devices.

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Non-Quasi-Static RF Model for SOI FinFET and Its Verification

  • Kang, In-Man
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.10 no.2
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    • pp.160-164
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    • 2010
  • The radio frequency (RF) model of SOI FinFETs with gate length of 40 nm is verified by using a 3-dimensional (3-D) device simulator. This paper shows the equivalent circuit model which can be used in the circuit analysis simulator. The RMS modeling error of Y-parameter was calculated to be only 0.3 %.

Dynamics of Pore Growth in Membranes and Membrane Stability

  • W. Sung;Park, P. J.
    • Proceedings of the Korean Biophysical Society Conference
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    • 1998.06a
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    • pp.15-15
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    • 1998
  • Pores can form and grow in biomembranes because of factors such as thermal fluctuation, transmembrane electrical potential, and cellular environment. We propose a new statistical physics model of the pore growth treated as a non-Markovian stochastic process, with a free energy barrier and memory friction from the membrane matrix treated as a quasi-two-dimensional viscoelastic and dielectric fluid continuum.(omitted)

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Micro-scale dependent static stress and strain analyses of thickness-stretching micro plate in sport application

  • Mingjun Xia
    • Advances in concrete construction
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    • v.15 no.5
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    • pp.349-358
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    • 2023
  • Aim of this work is investigating effect of thickness-stretching formulation on the quasi three-dimensional analysis of micro plate based on a thickness-stretched and shear deformable model through principle of virtual work and micro-scale dependent constitutive relations. Governing differential equations are derived in terms of five unknown functions and the analytical solution is derived using Navier's technique. To explore effect of thickness stretching model on the static results, a comparison between the results with and without thickness stretching effect is presented.