二阶非线性脉冲微分方程的振动性

考虑二阶脉冲微分方程(r(t)(x′(t))σ)′+f(t,x(t),x′(t))=0,t t0,t≠tk,k=1,2,…x(tk+)=gk(x(tk)),x′(tk+)=hk(x′(tk)),k=1,2,…(E)其中0 t0相似文献   

A mathematical model for fungal development in heterogeneous environments

A mathematical model for the development of fungal mycelia in heterogeneous environmental conditions is presented. The validity of this model is tested by comparison of numerical simulations with experimental observations.     

Asymptotic behavior of solutions of second-order nonlinear impulsive differential equations

In this work, the asymptotic behavior of all solutions of second-order nonlinear ordinary differential equations with impulses is investigated. By impulsive differential inequality and Riccati transformation, sufficient conditions of asymptotic behavior of all solutions of second-order nonlinear ordinary differential equations with impulses are obtained. An example is also inserted to illustrate the impulsive effect.     

On Nonlinear Hyperbolic Functional Differential Equations

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Asymptotic Behavior of Forced Nonlinear Delay Differential Equations with Impulses

The purpose of this paper is to investigate the asymptotic behavior of solutions of the forced nonlinear delay differential equations with impulses Our results, which hold for linear and nonlinear equations, forced and unforced equations, impulsive and nonimpulsive equations, improve and generalize the known results recently obtained in [8]. Received September 7, 1997, Revised May 26, 1998, Accepted July 15, 1998     

脉冲强迫非线性时滞微分方程的渐近性

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A mathematical model of silicon-based thermobiosensors

A mathematical model of a silicon glucose thermobiosensor thatdetects changes in temperature produced by a biocatalytic reactionis proposed for calculation of transient temperature and reactantconcentration profiles, time-dependencies of the output signal,and calibration curves. Mathematically the model is reducedto a one-dimensional linear initial-boundary-value problem ofthe heat-conduction equation with a thermal source F(x, t).In order to find F(x, t), a system of the second-order nonlinearpartial differential equations for glucose and oxygen concentrations,describing a combination of diffusion-membrane theory and Michaelis-Mentenenzyme reaction theory, has been solved. The computed dependenciesof transient temperature profile and sensor response to variousconditions such as oxygen buffer concentration, membrane thickness,enzyme loading, and operation mode are analysed for the optimaldesign of the tensor.     

二阶非线性微分方程的振动准则

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关于Ou—Iang型非线性积分不等式

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二阶非线性微分方程的单调解

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二阶非线性椭圆型微分方程振动的区域准则

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二阶非线性中立型泛函微分方程的振动准则

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A mathematical model of imbibition phenomenon in heterogeneous porous media during secondary oil recovery process

The present paper discuses the solution of one-dimensional mathematical model for counter-current water imbibition phenomenon occurring into an oil-saturated cylindrical heterogeneous porous matrix. During secondary oil recovery process when water is injected in oil formatted heterogeneous porous matrix then at common interface the counter current imbibition phenomenon occurs due to the difference of viscosity of water and oil which satisfies imbibition condition _Vi=-_Vn$V_i=-V_n$. The governing differential equation of this phenomenon is in the form of non-linear partial differential equation which has been converted into non-linear ordinary differential by using similarity transformation. The solution of this problem has been obtained in term of power series by using appropriate boundary condition at common interface. The graphical presentation is obtained by using MATLAB and final solution physically interpreted.     

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建立了三阶非线性微分方程…x+φ(x,x.,¨x)¨x+f(x,x.)=p(t,x,x.,¨x)的一切解有界和收敛到零的充分条件.