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1.
In this article, a way to employ the diffusion approximation to model interplay between TCP and UDP flows is presented. In order to control traffic congestion, an environment of IP routers applying AQM (Active Queue Management) algorithms has been introduced. Furthermore, the impact of the fractional controller PIγ and its parameters on the transport protocols is investigated. The controller has been elaborated in accordance with the control theory. The TCP and UDP flows are transmitted simultaneously and are mutually independent. Only the TCP is controlled by the AQM algorithm. Our diffusion model allows a single TCP or UDP flow to start or end at any time, which distinguishes it from those previously described in the literature.  相似文献   
2.
In this paper, we study the Holder regularity of weak solutions to the Dirichlet problem associated with the regional fractional Laplacian (-△)αΩ on a bounded open set Ω ■R(N ≥ 2) with C(1,1) boundary ■Ω. We prove that when f ∈ Lp(Ω), and g ∈ C(Ω), the following problem (-△)αΩu = f in Ω, u = g on ■Ω, admits a unique weak solution u ∈ W(α,2)(Ω) ∩ C(Ω),where p >N/2-2α and 1/2< α < 1. To solve this problem, we consider it into two special cases, i.e.,g ≡ 0 on ■Ω and f ≡ 0 in Ω. Finally, taking into account the preceding two cases, the general conclusion is drawn.  相似文献   
3.
In this paper, we define interval‐valued left‐sided and right‐sided generalized fractional double integrals. We establish inequalities of Hermite‐Hadamard like for coordinated interval‐valued convex functions by applying our newly defined integrals.  相似文献   
4.
In the paper mentioned in the title, it is proved the boundedness of the Riesz potential operator of variable order α(x) from variable exponent Morrey space to variable exponent Campanato space, under certain assumptions on the variable exponents p(x) and λ(x) of the Morrey space. Assumptions on the exponents were different depending on whether α ( x ) p ( x ) ? n + λ ( x ) p ( x ) takes or not the critical values 0 or 1. In this note, we improve those results by unifying all the cases and covering the whole range 0 ? α ( x ) p ( x ) ? n + λ ( x ) p ( x ) ? 1. We also provide a correction to some minor technicality in the proof of Theorem 2 in the aforementioned paper.  相似文献   
5.
This work is concerned with the extension of the Jacobi spectral Galerkin method to a class of nonlinear fractional pantograph differential equations. First, the fractional differential equation is converted to a nonlinear Volterra integral equation with weakly singular kernel. Second, we analyze the existence and uniqueness of solutions for the obtained integral equation. Then, the Galerkin method is used for solving the equivalent integral equation. The error estimates for the proposed method are also investigated. Finally, illustrative examples are presented to confirm our theoretical analysis.  相似文献   
6.
在p-adic域上研究分数次Hardy型算子与CMO(Q_p~n)函数生成的多线性交换子,建立了交换子在Lebesgue空间和Herz空间上的有界性.对Hardy算子的多线性交换子也得到了相应的结果.  相似文献   
7.
The purpose of this article is to investigate high‐order numerical approximations of scalar conservation laws with nonlocal viscous term. The viscous term is given in the form of convolution in space variable. With the help of the characteristic of viscous term, we design a semidiscrete local discontinuous Galerkin (LDG) method to solve the nonlocal model. We prove stability and convergence of semidiscrete LDG method in L2 norm. The theoretical analysis reveals that the present numerical scheme is stable with optimal convergence order for the linear case, and it is stable with sub‐optimal convergence order for nonlinear case. To demonstrate the validity and accuracy of our scheme, we test the Burgers equation with two typical nonlocal fractional viscous terms. The numerical results show the convergence order accuracy in space for both linear and nonlinear cases. Some numerical simulations are provided to show the robustness and effectiveness of the present numerical scheme.  相似文献   
8.
吴奎  邵珠山  秦溯 《力学学报》2020,52(3):890-900
高地应力深埋软岩隧道大变形问题已成为隧道工程建设领域的突出难题. 根据高地应力深埋软岩隧道的变形特征, 基于"围岩能量吸收、变形释放"的让压支护是解决软岩隧道大变形问题的有效方法. 针对流变岩体中深埋圆形隧道在让压支护作用下的力学响应问题, 通过引入分数阶微积分理论, 采用Abel黏壶元件建立了改进的分数阶Burgers蠕变模型来表征围岩的时效变形. 此外, 通过在让压支护不同变形阶段引入刚度修正系数, 克服了传统支护未能考虑围岩变形释放的问题. 据此, 本文推导了在考虑支护延迟安装影响下, 不同变形阶段围岩与让压支护相互作用的解析解. 为了验证理论研究的正确性, 对一算例进行了不同解答及工程结果的比对, 吻合较好. 最后, 参数研究结果表明: 围岩与让压支护间的相互作用受蠕变本构模型分数阶阶数影响较大. 隧道的位移或支护压力与让压位移、支护刚度修正系数间存在线性比例关系, 但由于刚度修正系数仅保持在较小的变化范围内, 隧道的位移或支护压力变化并不显著.   相似文献   
9.
This article proposes a new fractional-order discrete-time chaotic system, without equilibria, included two quadratic nonlinearities terms. The dynamics of this system were experimentally investigated via bifurcation diagrams and largest Lyapunov exponent. Besides, some chaotic tests such as the 0–1 test and approximate entropy (ApEn) were included to detect the performance of our numerical results. Furthermore, a valid control method of stabilization is introduced to regulate the proposed system in such a way as to force all its states to adaptively tend toward the equilibrium point at zero. All theoretical findings in this work have been verified numerically using MATLAB software package.  相似文献   
10.
In this paper, we study certain interesting and useful properties of incomplete -functions. The incomplete -function is an extension of the -function. We find several useful classical integral transforms of these functions. Further, we examine the fractional calculus with the incomplete -functions and point out several special cases. Finally, we give the applications of incomplete -functions in detecting glucose supply in human blood.  相似文献   
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