• 제목/요약/키워드: Laplace integral

검색결과 95건 처리시간 0.023초

EXTREMAL DISTANCE AND GREEN'S FUNCTION

  • Chung, Bo Hyun
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제1권1호
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    • pp.29-33
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    • 1994
  • There are various aspects of the solution of boundary-value problems for second-order linear elliptic equations in two independent variables. One useful method of solving such boundary-value problems for Laplace's equation is by means of suitable integral representations of solutions and these representations are obtained most directly in terms of particular singular solutions, termed Green's functions.(omitted)

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혼합경계적분 요소법을 사용한 직교입사파랑의 반사율계산 모델 (A hybrid boundary integral equation model applied for the calculation of normal incident waves)

  • 서승남;김상익
    • 한국해안해양공학회:학술대회논문집
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    • 한국해안해양공학회 1991년도 정기학술강연회 발표논문 초록집
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    • pp.30-35
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    • 1991
  • 해저가 완만하게 변하는 해역 위를 지나는 파랑의 반사는 무시할 수 있으며 이에 대한 파랑계산 방법으로는 굴절 모델 (서 등, 1989)과 포물형 근사식 모델(서, 1990b)을 들 수 있다. 그러나 해저의 변화가 심해 상당량의 파랑에너지가 반사되는 경우에는 파랑 운동을 지배하는 원시 방정식인 Laplace을 사용하여야 한다.(중략)

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FRACTIONAL DIFFERENTIATIONS AND INTEGRATIONS OF QUADRUPLE HYPERGEOMETRIC SERIES

  • Bin-Saad, Maged G.;Nisar, Kottakkaran S.;Younis, Jihad A.
    • 대한수학회논문집
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    • 제36권3호
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    • pp.495-513
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    • 2021
  • The hypergeometric series of four variables are introduced and studied by Bin-Saad and Younis recently. In this line, we derive several fractional derivative formulas, integral representations and operational formulas for new quadruple hypergeometric series.

DISCRETE MULTIPLE HILBERT TYPE INEQUALITY WITH NON-HOMOGENEOUS KERNEL

  • Ban, Biserka Drascic;Pecaric, Josip;Peric, Ivan;Pogany, Tibor
    • 대한수학회지
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    • 제47권3호
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    • pp.537-546
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    • 2010
  • Multiple discrete Hilbert type inequalities are established in the case of non-homogeneous kernel function by means of Laplace integral representation of associated Dirichlet series. Using newly derived integral expressions for the Mordell-Tornheim Zeta function a set of subsequent special cases, interesting by themselves, are obtained as corollaries of the main inequality.

차량 감/가속시의 엔진의 동적 응답 해석 (Analysis of Transient Response of an Engine to Throttle Tip-in/Tip-out)

  • 고강호
    • 한국자동차공학회논문집
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    • 제10권4호
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    • pp.122-128
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    • 2002
  • In this paper dynamic responses of an engine, which is supported by hydraulic mount, to throttle tip-in/Tip out are analyzed. Because the hydraulic mounts have non-linearity that the characteristics of stiffness and damping vary with frequencies, it is difficult to analyze the dynamic behavior of an engine using general integral algorithms. Convolution integral and relationship between unit impulse response functions and frequency response functions are therefore used to simulate the transient behaviors of an engine indirectly. In time domain, impulse response functions are calculated by two-side discrete inverse courier transform of frequency response function achieved by laplace transform of equations of motion. Considering the fact that the shapes of behavior of an engine simulated by the proposed method are in good agreement with test results, it is confirmed that the proposed method is very effective for the analysis of transient response to throttle tip-in/out of an engine with hydraulic mounts.

Thermomechanical deformation in porous generalized thermoelastic body with variable material properties

  • Kumar, Rajneesh;Devi, Savita
    • Structural Engineering and Mechanics
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    • 제34권3호
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    • pp.285-300
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    • 2010
  • The two-dimensional deformation of a homogeneous, isotropic thermoelastic half-space with voids with variable modulus of elasticity and thermal conductivity subjected to thermomechanical boundary conditions has been investigated. The formulation is applied to the coupled theory(CT) as well as generalized theories: Lord and Shulman theory with one relaxation time(LS), Green and Lindsay theory with two relaxation times(GL) Chandrasekharaiah and Tzou theory with dual phase lag(C-T) of thermoelasticity. The Laplace and Fourier transforms techniques are used to solve the problem. As an application, concentrated/uniformly distributed mechanical or thermal sources have been considered to illustrate the utility of the approach. The integral transforms have been inverted by using a numerical inversion technique to obtain the components of displacement, stress, changes in volume fraction field and temperature distribution in the physical domain. The effect of dependence of modulus of elasticity on the components of stress, changes in volume fraction field and temperature distribution are illustrated graphically for a specific model. Different special cases are also deduced.

Response of temperature dependence of an elastic modulus in microstretch generalized thermoelasticity

  • Kumar, Rajneesh;Gupta, Rajani Rani
    • Structural Engineering and Mechanics
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    • 제30권5호
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    • pp.577-592
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    • 2008
  • Laplace-Fourier transform techniques are used to investigate the interaction caused by mechanical, thermal and microstress sources in a generalized thermomicrostretch elastic medium with temperature-dependent mechanical properties. The modulus of elasticity is taken as a linear function of reference temperature. The integral transforms are inverted using a numerical technique to obtain the normal stress, tangential stress, tangential couple stress, microstress and temperature distribution. Effect of temperature dependent modulus of elasticity and thermal relaxation times have been depicted graphically on the resulting quantities. Comparisons are made with the results predicted by the theories of generalized thermoelasticity. Some particular cases are also deduced from the present investigation.

A M-TYPE RISK MODEL WITH MARKOV-MODULATED PREMIUM RATE

  • Yu, Wen-Guang
    • Journal of applied mathematics & informatics
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    • 제27권5_6호
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    • pp.1033-1047
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    • 2009
  • In this paper, we consider a m-type risk model with Markov-modulated premium rate. A integral equation for the conditional ruin probability is obtained. A recursive inequality for the ruin probability with the stationary initial distribution and the upper bound for the ruin probability with no initial reserve are given. A system of Laplace transforms of non-ruin probabilities, given the initial environment state, is established from a system of integro-differential equations. In the two-state model, explicit formulas for non-ruin probabilities are obtained when the initial reserve is zero or when both claim size distributions belong to the $K_n$-family, n $\in$ $N^+$ One example is given with claim sizes that have exponential distributions.

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Wave propagation of graphene platelets reinforced metal foams circular plates

  • Lei-Lei Gan;Jia-Qin Xu;Gui-Lin She
    • Structural Engineering and Mechanics
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    • 제85권5호
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    • pp.645-654
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    • 2023
  • Based on first-order shear deformation theory, a wave propagation model of graphene platelets reinforced metal foams (GPLRMFs) circular plates is built in this paper. The expressions of phase-/group- velocities and wave number are obtained by using Laplace integral transformation and Hankel integral transformation. The effects of GPLs pattern, foams distribution, GPLs weight fraction and foam coefficient on the phase and group velocity of GPLRMFs circular plates are discussed in detail. It can be inferred that GPLs distribution have great impacts on the wave propagation problems, and Porosity-I type distribution has the largest phase velocity and group velocity, followed by Porosity-III, and finally Porosity-II; With the increase of the GPLs weight fraction, the phase- and group- velocities for the GPLRMFs circular plate will be increased; With the increase of the foam coefficient, the phase- and group- velocities for the GPLRMFs circular plate will be decreased.