Fractional derivative statistical damage model of unsaturated expansive soil based on unified hydraulic effect

Unsaturated expansive soil is widely distributed in China and has complex engineering properties.This paper proposes the unified hydraulic effect shear strength theory of unsaturated expansive soil based on the effective stress principle,swelling force principle,and soil–water characteristics.Considering the viscoelasticity and structural damage of unsaturated expansive soil during loading,a fractional hardening–damage model of unsaturated expansive soil was established.The model parameters were established on the basis of the proposed calculation method of shear strength and the triaxial shear experiment on unsaturated expansive soil.The proposed model was verified by the experimental data and a traditional damage model.The proposed model can satisfactorily describe the entire process of the strain-hardening law of unsaturated expansive soil.Finally,by investigating the damage variables of the proposed model,it was found that:(a)when the values of confining pressure and matric suction are close,the coupling of confining pressure and matric suction contributes more to the shear strength;(b)there is a damage threshold for unsaturated expansive soil,and is mainly reflected by strength criterion of infinitesimal body;(c)the strain hardening law of unsaturated expansive soil is mainly reflected by fractional derivative operator.

The Limiting Case of Blending Differences for Bivariate Blending Continued Fraction Expansions

For a univariate function given by its Taylor series expansion, a continued fraction expansion can be obtained with the Viscovatov＇s algorithm, as the limiting value of a Thiele interpolating continued fraction or by means of the determinantal formulas for inverse and reciprocal differences with coincident data points. In this paper, both Viscovatov-like algorithms and Taylor-like expansions are incorporated to yield bivariate blending continued expansions which are computed as the limiting value of bivariate blending rational interpolants, which are constructed based on symmetric blending differences. Numerical examples are given to show the effectiveness of our methods.

Exact solutions of nonlinear fractional differential equations by (G'/G)-expansion method

In this paper, we use the fractional complex transform and the （G＇/G）-expansion method to study the nonlinear fractional differential equations and find the exact solutions. The fractional complex transform is proposed to convert a partial fractional differential equation with Jumarie＇s modified Riemann-Liouville derivative into its ordinary differential equation. It is shown that the considered transform and method are very efficient and powerful in solving wide classes of nonlinear fractional order equations.

Exact Solution to Nonlinear Differential Equations of Fractional Order via (<i>G’</i>/<i>G</i>)-Expansion Method

In this article, a new application to find the exact solutions of nonlinear partial time-space fractional differential Equation has been discussed. Firstly, the fractional complex transformation has been implemented to convert nonlinear partial fractional differential Equations into nonlinear ordinary differential Equations. Afterwards, the (G'/G)-expansion method has been implemented, to celebrate the exact solutions of these Equations, in the sense of modified Riemann-Liouville derivative. As application, the exact solutions of time-space fractional Burgers’ Equation have been discussed.

Algorithm for Fast Calculation of Hirzebruch-Jung Continued Fraction Expansions to Coding of Graph Manifolds

We present a new algorithm for the fast expansion of rational numbers into continued fractions. This algorithm permits to compute the complete set of integer Euler numbers of the sophisticate tree graph manifolds, which we used to simulate the coupling constant hierarchy for the universe with five fundamental interactions. Moreover, we can explicitly compute the integer Laplacian block matrix associated with any tree plumbing graph. This matrix coincides up to sign with the integer linking matrix (the main topological invariant) of the graph manifold corresponding to the plumbing graph. The need for a special algorithm appeared during computations of these topological invariants of complicated graph manifolds since there emerged a set of special rational numbers (fractions) with huge numerators and denominators;for these rational numbers, the ordinary methods of expansion in continued fraction became unusable.

The Traveling Wave Solutions of Space-Time Fractional Differential Equation Using Fractional Riccati Expansion Method

In this paper, we firstly give a counterexample to indicate that the chain rule is lack of accuracy. After that, we put forward the fractional Riccati expansion method. No need to use the chain rule, we apply this method to fractional KdV-type and fractional Telegraph equations and obtain the tangent and cotangent functions solutions of these fractional equations for the first time.

Two Dual Expansions for Generalized Bivariate Thiele-Type Matrix Valued Interpolating Continued Fractions

A new method for the construction of bivariate matrix valued rational interpolants on a rectangulargrid is introduced. The rational interpolants are expressed in the continued fraction form with scalardenominator. Tile matrix quotients are based oil the generalized inverse for a matrix, Which is found to beeffective in continued fraction interpolation. In this paper, tWo dual expansions for bivariate matrix valuedThiele-type interpolating continued fractions are presented, then, tWo dual rational interpolants are definedout of them.

一个含离散型分式核的Hilbert型不等式

引入若干正参数,新构建了一个分式型的离散形态的核函数,并借助于权系数的方法,建立了一个二重Hilbert型级数不等式,并证明此不等式的常数因子是最佳取值.另外,根据余割函数的有理分式展开形式,给出最佳常数因子的余割函数表示形式.通过对参数赋予一些特殊数值,得到了一些已有结果,并且给出了一些新的含特殊核函数的Hilbert型不等式.

改进的tan■-展开法和几类非线性分数阶发展方程

运用改进的tan■-展开法,以一阶常系数微分方程为辅助方程,结合齐次平衡原理,研究了非线性分数阶Khokhlov-Zabolotskaya-Kuznetsov(KZK)方程、非线性分数阶foam drainage方程、非线性分数阶Jimbo-Miwa(JM)方程.借助符号计算系统Maple,求出了方程的多种精确解,这些解包括周期解、孤子解、有理函数解、指数函数解,扩大了解的范围.

基于ESO的气流引纬滑模分数阶反步控制

针对气流引纬纱线在飞行过程中存在不确定时变因素和未建模问题,提出了一种基于有限时间扩张状态观测器的神经积分滑模分数阶反步控制器。通过对纬纱在气流引纬过程的动力学分析,得到系统的状态方程,引入有限时间扩张状态观测器,对复合扰动问题进行有效估计降低跟踪误差,设计非线性积分滑模面,采用RBF神经网络对滑模面系数进行补偿修正,并融合到反步控制中保证了算法有限时间收敛和稳定性,在虚拟控制律中加入了分数阶理论,进一步提升了系统的稳定性和抗干扰能力。最后,为了使得引纬完成的时间更接近设定值,在筘幅中间额外增加了4个探纬器,并对纱线的运动状态做出调整。研究设计的控制器和改善的引纬结构使得引纬完成的时间更接近设定值,研究验证了所设计方案的有效性。

基于MATLAB的赖特函数分区算法研究及实现

物理数学中的多数特殊函数可将复平面划分区域采用不同数值技术来计算。赖特函数在分数微积分及其工程应用中有着重要作用,作为一类新型特殊函数也可使用分区算法进行数值计算。通过研究赖特函数在大参数下的渐近展开式和公式中系数的计算方法,修正积分表达式及积分半径选择定理的错误,进一步改进完善复数域赖特函数的分区算法,并利用MATLAB软件进行编程仿真分析算法精度。实验结果表明,分区算法的适用性广,有良好逼近效果。

含油、固污水对泡沫液发泡性能的影响研究

为指导消防污水的处理回用,选取柴油、汽油2种典型成品油以及硅胶、二氧化硅2种微米级固体粉末配置不同含量的污水发泡,测试油、固含量对发泡性能的影响。结果表明:在0~3%质量分数范围内,柴油主要影响发泡倍数,降幅可达40.15%;汽油主要影响25%析液时间,降幅可达33.05%;直径大于10μm的固体颗粒对发泡倍数和析液时间均有影响,前者降幅可达25.22%,后者降幅可达18.49%。

一个关联余切函数高阶导数的Hilbert型不等式

通过引入多个参数,借助余切函数的部分分式展开式,在全平面上建立了最佳常数因子及与余切函数的高阶导数有关的Hilbert型不等式及其等价形式。特别地,通过对参数赋值,还给出了一些特殊的在全平面上的Hilbert型不等式。

Sylvester连分数展式中若干例外集的Hausdorff维数

对于任意实数x∈(0,1],记x=[d_(1),d_(2),···]为x的Sylvester连分数展式,令ψ(n)为N上的正函数,本文研究了集合A(ψ):■的Hausdorff维数.通过构造覆盖和合适的Cantor型子集,我们得到了该集合的精确维数为■同时,本文还考虑了Sylvester连分数展式的部分商满足■的极限是零或无穷时的集合的Hausdorff维数.

关于一个新的Ro-Ramanujan型连分数

引入新的Rogers-Ramanujan型恒等式,通过猜测相关量和证明递归关系,给出了一个新的Rogers-Ramanujan型连分数,对先前Rogers-Ramanujan的连分数展开列表进行扩充.

一类时空分数阶爆破孤立子方程组的新解法

为得到一类时空分数阶爆破孤立子方程组的新精确解,本文采用了一种新的解法——拓展的(G'/G)-展开方法。首先通过行波变换,将原分数阶偏微分方程组转化为整数阶非线性常微分方程组,其次结合齐次平衡原理,增加负幂次项,将含有相同次数的幂结合,并令同次幂系数为零,再运用数学软件MATLAB求解相应的系数方程组,得出该方程新的含有参数形式的精确解。结果表明:拓展的(G'/G)-展开方法能丰富这类分数阶偏微分方程的精确解。

ON COLLISION LOCAL TIME OF TWO INDEPENDENT FRACTIONAL ORNSTEIN-UHLENBECK PROCESSES

In this article, we study the existence of collision local time of two indepen- dent d-dimensional fractional Ornstein-Uhlenbeck processes X＋^H1 and Xt^H2 with different parameters Hi ∈ （0, 1）,i = 1, 2. Under the canonical framework of white noise analysis, we characterize the collision local time as a Hida distribution and obtain its＇ chaos expansion. Key words Collision local time; fractional Ornstein-Uhlenbeck processes; generalized white noise functionals; choas expansion

Some Numerical Extrapolation Methods for the Fractional Sub-diffusion Equation and Fractional Wave Equation Based on the L1 Formula

With the help of the asymptotic expansion for the classic Li formula and based on the L1-type compact difference scheme,we propose a temporal Richardson extrapolation method for the fractional sub-diffusion equation.Three extrapolation formulas are presented,whose temporal convergence orders in L_(∞)-norm are proved to be 2,3-α,and 4-2α,respectively,where 0<α<1.Similarly,by the method of order reduction,an extrapola-tion method is constructed for the fractional wave equation including two extrapolation formulas,which achieve temporal 4-γ and 6-2γ order in L_(∞)-norm,respectively,where1<γ<2.Combining the derived extrapolation methods with the fast algorithm for Caputo fractional derivative based on the sum-of-exponential approximation,the fast extrapolation methods are obtained which reduce the computational complexity significantly while keep-ing the accuracy.Several numerical experiments confirm the theoretical results.

Exact solutions for nonlinear partial fractional differential equations

′In this article, we use the fractional complex transformation to convert nonlinear partial fractional differential equations to nonlinear ordinary differential equations. We use the improved （G′/G）-expansion function method to calculate the exact solutions to the time- and space-fractional derivative foam drainage equation and the time- and space-fractional derivative nonlinear KdV equation. This method is efficient and powerful for solving wide classes of nonlinear evolution fractional order equations.

REMARKS ON SUB-FRACTIONAL BESSEL PROCESSES

Let S = {（St1,···,Std ）}t≥0 denote a d-dimensional sub-fractional Brownian motion with index H ≥ 1/2. In this paper we study some properties of the process X of the formwhere Rt = （（St1）2＋···＋（Std）2）~1/2 is the sub-fractional Bessel process.