• Title/Summary/Keyword: Green함수

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Approximation of Green Warranty Function by Radon Radial Basis Function Network (Radon RBF Network에 의해 그린 보증 함수의 근사화)

  • Lee, Sang-Hyun;Lim, Jong-Han;Moon, Kyung-Li
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.12 no.3
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    • pp.123-131
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    • 2012
  • As the price of traditional fuels soar, the alternatives are becoming more viable. And manufacturers are promoting the growing viability of electric and biofuel-powered vehicles through longer warranties. Now, these longer green environment (emission)warranties, sometimes called extended warranties or "super warranties," have been adapted. The main result of this paper is to present a new method to approximate a bivariate warranty function by using Radial Basis Function Network with application of Radon Transform and its inverse which is used to reduce the dimension of the warranty space. This method consist of the following stages: First, by using the Radon Transform, the bivariate warranty function can be reduced to one dimensional function. Second, each of the one dimensional functions is approximated by using neural network technique into neural sub-networks. Third, these neural sub-networks are combined together to form the final approximation neural network. Four, by using the inverse of radon transform to this final approximation neural network we get the approximation to the given function. Also, we apply the above method to some green warranty data of automotive vehicle company.

Development of a CPInterface (COMSOL-PyLith Interface) for Finite Source Inversion using the Physics-based Green's Function Matrix (물리 기반 유한 단층 미끌림 역산을 위한 CPInterface (COMSOL-PyLith Interface) 개발)

  • Minsu Kim;Byung-Dal So
    • Geophysics and Geophysical Exploration
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    • v.26 no.4
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    • pp.268-274
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    • 2023
  • Finite source inversion is performed with a Green's function matrix and geodetic coseismic displacement. Conventionally, the Green's function matrix is constructed using the Okada model (Okada, 1985). However, for more realistic earthquake simulations, recent research has widely adopted the physics-based model, which can consider various material properties such as elasticity, viscoelasticity, and elastoplasticity. We used the physics-based software PyLith, which is suitable for earthquake modeling. However, the PyLith does not provide a mesh generator, which makes it difficult to perform finite source inversions that require numerous subfaults and observation points within the model. Therefore, in this study, we developed CPInterface (COMSOL-PyLith Interface) to improve the convenience of finite source inversion by combining the processes of creating a numerical model including sub-faults and observation points, simulating earthquake modeling, and constructing a Green's function matrix. CPInterface combines the grid generator of COMSOL with PyLith to generate the Green's function matrix automatically. CPInterface controls model and fault information with simple parameters. In addition, elastic subsurface anomalies and GPS observations can be placed flexibly in the model. CPInterface is expected to enhance the accessibility of physics-based finite source inversions by automatically generating the Green's function matrix.

An Analysis of Axisymmetric Two Dimensional Heat Diffusion Equation to Measure the Thermal Diffusivity of Layered Materials (積層材料의 熱擴散係數測定을 위한 軸對稱 二次元 熱擴散方程式의 解析)

  • 김진원;이흥주
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.10 no.3
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    • pp.349-356
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    • 1986
  • For the extension of application in flash method measuring the thermophysical properties of materials, the heat diffusion equation with the heat transfer loss from front, rear, and circumferential surfaces of two layer cylinderical sample is mathematically analyzed by means of Green's function for axially symmetric pulse heating on the front of samples. The solutions are applied to determine the unknown thermal diffusivity of the two materials and analyzed the measurement error due to heat loss and finite pulse time effects.

Analysis of added resistance of a ship advancing in waves (파랑중에서 전진하는 선박의 부가저항 해석)

  • 이호영;곽영기
    • Journal of Ocean Engineering and Technology
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    • v.11 no.2
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    • pp.91-99
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    • 1997
  • This paper presents theoretical formulations and numerical computations for predicting first-and second-order hydrodynamic force on a ship advvancing in waves. The theoretical formulation leads to linearized radiation and diffration problems solving the three-dimensional Green function integral equations over the mean wetted body surface. Green function representing a translating and pulsating source potantial for infinite water depth is used. In order to solve integral equations for three dimentional flows using Green function efficiently, the Hoff's method is adopted for numerical calculation of the Green function. Based on the first-order solution, the mean seconder-order forces and moments are obtained by directly integrating second-order pressure over the mean wetted body surface. The calculated items are carried out for analyzing the seakeeping characteristics of Series 60. The calculated items are hydrodynamic coefficients, wave exciting forces, frequency response functions and addd resistance in waves.

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Fast Scattered-Field Calculation Using Windowed Green Functions (윈도우 그린함수를 이용한 고속 산란필드 계산)

  • 주세훈;김형동
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2001.11a
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    • pp.7-11
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    • 2001
  • 본 논문에서는 방사 적분방정식의 해를 구하기 위하여 파수영역 웨이블릿 변환개념에 기반을 둔 윈도우 그린함수를 사용하여 파수영역에서 고속으로 산란필드를 계산하는 방법을 제안하였다. 그린함수에 적용된 파수영역 웨이블릿 변환은 공간영역에서 동일한 Q를 갖는 윈도우를 사용하여 필터링함으로써 등가적으로 구현하였다. 고유함수를 이용하여 관찰점을 중심으로 전개된 그린함수를 푸리에 변환한 후 파수영역에서 방사 적분을 계산함으로써 계산효율을 얻을 수 있음을 확인하였다. 관찰영역에서만 정확한 값을 갖는 고유함수로 전개된 그린함수는 그린함수에 윈도우 함수를 씌운 형태로 방사 적분방정식의 파수영역 표현에 적용하면 기존의 고속멀티폴법과 동일한 산란필드 공식을 얻을 수 있다.

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A New Analysis of Waveguide Structure Using the Iterative Green's Function Method Applicable to the Electromagnetics Instruction (전파 교육에 적용할 수 있는 반복 그린함수 방법을 이용한 전자파 도파관 구조의 새로운 해석법)

  • 조용희
    • Proceedings of the Korea Contents Association Conference
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    • 2003.05a
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    • pp.403-405
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    • 2003
  • An iterative Green's function method (IGFM) is introduced to analyze complex electromagnetic waveguide structures in view of the university student. The IGFM utilizes the Green's function and iteration scheme. The physical mechanism with simple mathematical equations is used to formulate the IGFM. Scattering characteristics of a standard E-plane T-junction in a parallel-plate waveguide are theoretically investigated in terms of the IGFM. Numerical computations illustrate the characteristics of resection and transmission powers versus frequency. A dominant-mode solution is presented and compared with the higher-mode solutions.

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Scattering Characteristics of the Infinite Strip Conductor for TE Waves (무환히 긴 도체 스트립의 TE파 산란 특성)

  • Chang, Jae-Sung;Lee, Sang-Seol
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.26 no.5
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    • pp.18-22
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    • 1989
  • We calculate the distribution of the induced current on the strip by the TE waves on the infinite conducting strip. The boundary equations represented as the spatial domain function becomevery complicated equations including convolution integral. As we transform it to the spectral domain, we have a very simple equation expressed by some algebraic multiplication of the current density function and Green's function. It is shown that the computation result of the induced current distribution gives the optimum value, when the stop condition of iteration presented in this paper are satisfied.

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Scattering Characteristics of The Infinite Strip Conductor for TM Waves (무한히 긴 도체 스트립의 TM파 산란 특성)

  • 장재성;이상설
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.13 no.5
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    • pp.437-443
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    • 1988
  • We calculate the distribution of the current on the strip by the incident waves on the infinite conducting strip line. The boundary equations represented as the spatial domain function become very complicated equations including convolution integral. Transformed it to the spectral domain, we have a very simple equation is composed by some algebraic multiplication of the current density function and Green's function. the acceleration of iteration procedure is achieved by Kastner's method. The result of iteration gives us the optimum value when it satisfies the iteration stop condition presented in this paper. We confirmed that the induced current density distribution on the stripline has been changed as variaties of the width.

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Closed-Form Green's Function for the Analysis of Microstrip Structure (마이크로스트립 구조 해석을 위한 Closed-Form 그린 함수)

  • Yang, Seung-Woo;Kim, Sung-Jin;Kim, Gun-Woo;Lee, Taek-Kyung
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.19 no.3
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    • pp.281-293
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    • 2008
  • In the layered medium, the Sommerfeld integral must be evaluated to calculate a space domain Green's function. The real axis integration method provides stable and accurate results over wide ranges of the observation distance and the singnal frequency. But this method has the in efficiency of approximation when the field point z is changed. Also, as the amplitude of z increases, the change of the spectral domain function is more rapidly. Therefore, the approximation is difficult when z becomes larger. In this paper, we propose a method to calculate an accurate closed-form Green's function for microstrip structure by using the closed-loop integration path.

A Study of Stability Analysis on Unsaturated Weathered Slopes Based on Rainfall-induced Wetting (강우시 습윤에 의한 불포화 풍화토의 사면 안정 해석 연구)

  • 김재홍;박성완;정상섭;유지형
    • Journal of the Korean Geotechnical Society
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    • v.18 no.2
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    • pp.123-136
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    • 2002
  • The infiltration of prolonged rainfall causes shallow slope failures on surficial slopes. Experiments performed on soil-water characteristic curves in weathered soils of three different types(SW, SP, SM) were used to construct a general equation for the soil-water characteristic curve. Based on this, the saturated depth by Green & Ampt model was compared with the results of numerical analyses and the range of application of Green & Ampt model was evaluated. It was found that the saturated depth occurred by infiltration on the surface of slopes has an inf1uence on the surficial stability of slopes md, the stability analysis of unsaturated soils calculated by using the soil-water characteristic curve of weathered soils was found to be a proper analysis for shallow slope failures due to rainfall.