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Prediction of ILI following the COVID-19 pandemic in China by using a partial differential equation
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作者 Xu Zhang Yu-Rong Song Ru-Qi Li 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期118-128,共11页
The COVID-19 outbreak has significantly disrupted the lives of individuals worldwide.Following the lifting of COVID-19 interventions,there is a heightened risk of future outbreaks from other circulating respiratory in... The COVID-19 outbreak has significantly disrupted the lives of individuals worldwide.Following the lifting of COVID-19 interventions,there is a heightened risk of future outbreaks from other circulating respiratory infections,such as influenza-like illness(ILI).Accurate prediction models for ILI cases are crucial in enabling governments to implement necessary measures and persuade individuals to adopt personal precautions against the disease.This paper aims to provide a forecasting model for ILI cases with actual cases.We propose a specific model utilizing the partial differential equation(PDE)that will be developed and validated using real-world data obtained from the Chinese National Influenza Center.Our model combines the effects of transboundary spread among regions in China mainland and human activities’impact on ILI transmission dynamics.The simulated results demonstrate that our model achieves excellent predictive performance.Additionally,relevant factors influencing the dissemination are further examined in our analysis.Furthermore,we investigate the effectiveness of travel restrictions on ILI cases.Results can be used to utilize to mitigate the spread of disease. 展开更多
关键词 partial differential equations INFLUENZA SIS model PREDICTION
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Oscillation for Solutions of Systems of High Order Partial Differential Equations of Neutral Type 被引量:8
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作者 LIN Wen-xian(Department of Mathematics, Hanshan Teacher’s College, Chaozhou 521041, China) 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第2期168-174,共7页
In this paper, sane sufficient conditions are obtained for the oscillation for solutions of systems of high order partial differential equations of neutral type.
关键词 neutral type system of partial differential equations OSCILLATION
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Oscillation of Nonlinear Impulsive Delay Hyperbolic Partial Differential Equations 被引量:2
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作者 罗李平 彭白玉 欧阳自根 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第3期439-444,共6页
In this paper,by making use of the calculous technique and some results of the impulsive differential inequality,oscillatory properties of the solutions of certain nonlinear impulsive delay hyperbolic partial differen... In this paper,by making use of the calculous technique and some results of the impulsive differential inequality,oscillatory properties of the solutions of certain nonlinear impulsive delay hyperbolic partial differential equations with nonlinear diffusion coefficient are investigated.Sufficient conditions for oscillations of such equations are obtained. 展开更多
关键词 NONLINEAR IMPULSE DELAY hyperbolic partial differential equations OSCILLATION
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A lattice Boltzmann model with an amending function for simulating nonlinear partial differential equations 被引量:1
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作者 陈林婕 马昌凤 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第1期148-155,共8页
This paper proposes a lattice Boltzmann model with an amending function for one-dimensional nonlinear partial differential equations (NPDEs) in the form ut +αuux +βu^nuz +γuxx +δuzxx +ζxxxx = 0. This model... This paper proposes a lattice Boltzmann model with an amending function for one-dimensional nonlinear partial differential equations (NPDEs) in the form ut +αuux +βu^nuz +γuxx +δuzxx +ζxxxx = 0. This model is different from existing models because it lets the time step be equivalent to the square of the space step and derives higher accuracy and nonlinear terms in NPDEs. With the Chapman-Enskog expansion, the governing evolution equation is recovered correctly from the continuous Boltzmann equation. The numerical results agree well with the analytical solutions. 展开更多
关键词 nonlinear partial differential equation lattice Boltzmann method Chapman-Enskog expansion Taylor expansion
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Adaptive multi-step piecewise interpolation reproducing kernel method for solving the nonlinear time-fractional partial differential equation arising from financial economics 被引量:1
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作者 杜明婧 孙宝军 凯歌 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期53-57,共5页
This paper is aimed at solving the nonlinear time-fractional partial differential equation with two small parameters arising from option pricing model in financial economics.The traditional reproducing kernel(RK)metho... This paper is aimed at solving the nonlinear time-fractional partial differential equation with two small parameters arising from option pricing model in financial economics.The traditional reproducing kernel(RK)method which deals with this problem is very troublesome.This paper proposes a new method by adaptive multi-step piecewise interpolation reproducing kernel(AMPIRK)method for the first time.This method has three obvious advantages which are as follows.Firstly,the piecewise number is reduced.Secondly,the calculation accuracy is improved.Finally,the waste time caused by too many fragments is avoided.Then four numerical examples show that this new method has a higher precision and it is a more timesaving numerical method than the others.The research in this paper provides a powerful mathematical tool for solving time-fractional option pricing model which will play an important role in financial economics. 展开更多
关键词 time-fractional partial differential equation adaptive multi-step reproducing kernel method method numerical solution
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THE EXISTENCE OF INFINITELY MANY SO UTIONS OF QUASILINEAR PARTIAL DIFFERENTIAL EQUATIONS IN UNBOUNDED DOMAINS 被引量:1
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作者 李工宝 《Acta Mathematica Scientia》 SCIE CSCD 1989年第2期175-188,共14页
In this paper, we use the concentration-compactness principle together with the Mountain Pass Lemma to get the existence of nontrivial solutions and the existence of infinitely many solutions of the problem need not b... In this paper, we use the concentration-compactness principle together with the Mountain Pass Lemma to get the existence of nontrivial solutions and the existence of infinitely many solutions of the problem need not be compact operators from E to R~1. 展开更多
关键词 THE EXISTENCE OF INFINITELY MANY SO UTIONS OF QUASILINEAR partial differential equationS IN UNBOUNDED DOMAINS
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THREE-SPHERE INEQUALITIES FOR SECOND ORDER SINGULAR PARTIAL DIFFERENTIAL EQUATIONS
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作者 张松艳 《Acta Mathematica Scientia》 SCIE CSCD 2010年第3期993-1003,共11页
In this article, we give the three-sphere inequalities and three-ball inequalities for the singular elliptic equation div(A∨u) - Vu =0, and the three-ball inequalities on the characteristic plane and the three-cyli... In this article, we give the three-sphere inequalities and three-ball inequalities for the singular elliptic equation div(A∨u) - Vu =0, and the three-ball inequalities on the characteristic plane and the three-cylinder inequalities for the singular parabolic equation Эtu-div(A∨u) + Vu = 0, where the singular potential V belonging to the Kato-Fefferman- Phong's class. Some applications are also discussed. 展开更多
关键词 Three-sphere inequality three-cylinder inequality singular partial differential equation Kato-Fefferman-Phong's class Lipschitz domain
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Numerical Solution for Fractional Partial Differential Equation with Bernstein Polynomials
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作者 Jin-Sheng Wang Li-Qing Liu +1 位作者 Yi-Ming Chen Xiao-Hong Ke 《Journal of Electronic Science and Technology》 CAS 2014年第3期331-338,共8页
A framework to obtain numerical solution of the fractional partial differential equation using Bernstein polynomials is presented. The main characteristic behind this approach is that a fractional order operational ma... A framework to obtain numerical solution of the fractional partial differential equation using Bernstein polynomials is presented. The main characteristic behind this approach is that a fractional order operational matrix of Bernstein polynomials is derived. With the operational matrix, the equation is transformed into the products of several dependent matrixes which can also be regarded as the system of linear equations after dispersing the variable. By solving the linear equations, the numerical solutions are acquired. Only a small number of Bernstein polynomials are needed to obtain a satisfactory result. Numerical examples are provided to show that the method is computationally efficient. 展开更多
关键词 Absolute error Bernstein polynomials fractional partial differential equation numerical solution operational matrix
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abstract Operators and Higher-order Linear Partial Differential Equation
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作者 毕光庆 毕越凯 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第4期511-515,共5页
We summarize several relevant principles for the application of abstract operators in partial differential equations, and combine abstract operators with the Laplace transform. Thus we have developed the theory of par... We summarize several relevant principles for the application of abstract operators in partial differential equations, and combine abstract operators with the Laplace transform. Thus we have developed the theory of partial differential equations of abstract operators and obtained the explicit solutions of initial value problems for a class of higher-order linear partial differential equations. 展开更多
关键词 partial differential equations abstract operator SYMBOL laplace transform
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Element-free Galerkin (EFG) method for analysis of the time-fractional partial differential equations
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作者 Ge Hon-Xia Liu Yong-Qing Cheng Rong-Jun 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第1期46-51,共6页
The present paper deals with the numerical solution of time-fractional partial differential equations using the element-free Galerkin (EFG) method, which is based on the moving least-square approximation. Compared w... The present paper deals with the numerical solution of time-fractional partial differential equations using the element-free Galerkin (EFG) method, which is based on the moving least-square approximation. Compared with numerical methods based on meshes, the EFG method for time-fractional partial differential equations needs only scattered nodes instead of meshing the domain of the problem. It neither requires element connectivity nor suffers much degradation in accuracy when nodal arrangements are very irregular. In this method, the first-order time derivative is replaced by the Caputo fractional derivative of order α(0 〈 α≤ 1). The Galerkin weak form is used to obtain the discrete equations, and the essential boundary conditions are enforced by the penalty method. Several numerical examples are presented and the results we obtained are in good agreement with the exact solutions. 展开更多
关键词 element-free Galerkin (EFG) method meshless method time fractional partial differential equations
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Oscillation of Solutions for a Class of Nonlinear Neutral Partial Differential Equations with Continuous Distribution Delay
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作者 罗李平 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第1期67-74,共8页
In this paper, some sufficient conditions are obtained for the oscillation of solutions for a class of second order nonlinear neutral partial differential equations with continuous distribution delay under Robin and D... In this paper, some sufficient conditions are obtained for the oscillation of solutions for a class of second order nonlinear neutral partial differential equations with continuous distribution delay under Robin and Dirichlet's boundary value conditions. 展开更多
关键词 NONLINEAR NEUTRAL partial differential equation OSCILLATION continuous distribution delay
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Prediction of epidemics dynamics on networks with partial differential equations:A case study for COVID-19 in China
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作者 Ru-Qi Li Yu-Rong Song Guo-Ping Jiang 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第12期19-27,共9页
Since December 2019,the COVID-19 epidemic has repeatedly hit countries around the world due to various factors such as trade,national policies and the natural environment.To closely monitor the emergence of new COVID-... Since December 2019,the COVID-19 epidemic has repeatedly hit countries around the world due to various factors such as trade,national policies and the natural environment.To closely monitor the emergence of new COVID-19 clusters and ensure high prediction accuracy,we develop a new prediction framework for studying the spread of epidemic on networks based on partial differential equations(PDEs),which captures epidemic diffusion along the edges of a network driven by population flow data.In this paper,we focus on the effect of the population movement on the spread of COVID-19 in several cities from different geographic regions in China for describing the transmission characteristics of COVID-19.Experiment results show that the PDE model obtains relatively good prediction results compared with several typical mathematical models.Furthermore,we study the effectiveness of intervention measures,such as traffic lockdowns and social distancing,which provides a new approach for quantifying the effectiveness of the government policies toward controlling COVID-19 via the adaptive parameters of the model.To our knowledge,this work is the first attempt to apply the PDE model on networks with Baidu Migration Data for COVID-19 prediction. 展开更多
关键词 partial differential equations intervention measures Baidu Migration Data COVID-19 prediction
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CONORMAL SINGULARITIES FOR SOLUTION OF SEMILINEAR PARTIAL DIFFERENTIAL EQUATIONS
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作者 葛翔宇 《Acta Mathematica Scientia》 SCIE CSCD 1991年第4期425-432,共8页
In the studies of nonlinear partial differential equations, the influence, from the singularities of coefficients to the singularities of solution, is a field that has not been dealt with. In this paper, we discuss a ... In the studies of nonlinear partial differential equations, the influence, from the singularities of coefficients to the singularities of solution, is a field that has not been dealt with. In this paper, we discuss a simple case of semilinear equations under the frame of the space of conormal distributions. We prove the result that the solution has the same singularities on the hypersurface in which the coefficients have the conormal singularities. 展开更多
关键词 der CONORMAL SINGULARITIES FOR SOLUTION OF SEMILINEAR partial differential equationS 刁刀
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The Stability Research of the Finite Difference Scheme for a Nonlinear Partial Differential Equation
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作者 王秀琴 徐琛梅 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第3期394-399,共6页
The main purpose of this paper is to set up the finite difference scheme with incremental unknowns for the nonlinear differential equation by means of introducing incremental unknowns method and discuss the stability ... The main purpose of this paper is to set up the finite difference scheme with incremental unknowns for the nonlinear differential equation by means of introducing incremental unknowns method and discuss the stability of the scheme.Through the stability analyzing for the scheme,it was shown that the stability of the finite difference scheme with the incremental unknowns is improved when compared with the stability of the corresponding classic difference scheme. 展开更多
关键词 finite difference partial differential equation stability research incremental unknowns
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Remarks on Oscillation for Systems of High Order Partial Differential Equations of Neutral Type
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作者 LIN Wen-xian 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第4期537-542,共6页
In this paper, some sufficient conditions are obtained for the oscillation for solutions of systems of high order partial differential equations of neutral type.
关键词 neutral type system of partial differential equations OSCILLATION
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REFLECTED BACKWARD STOCHASTIC DIFFERENTIAL EQUATION WITH JUMPS AND VISCOSITY SOLUTION OF SECOND ORDER INTEGRO-DIFFERENTIAL EQUATION WITHOUT MONOTONICITY CONDITION: CASE WITH THE MEASURE OF LéVY INFINITE 被引量:1
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作者 Lamine SYLLA 《Acta Mathematica Scientia》 SCIE CSCD 2019年第3期819-844,共26页
We consider the problem of viscosity solution of integro-partial differential equation( IPDE in short) with one obstacle via the solution of reflected backward stochastic dif ferential equations(RBSDE in short) with j... We consider the problem of viscosity solution of integro-partial differential equation( IPDE in short) with one obstacle via the solution of reflected backward stochastic dif ferential equations(RBSDE in short) with jumps. We show the existence and uniqueness of a continuous viscosity solution of equation with non local terms, if the generator is not monotonous and Levy's measure is infinite. 展开更多
关键词 Integro-partial differential equation reflected stochastic differential equations with JUMPS viscosity solution NON-LOCAL operator
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Field Method for Integrating the First Order Differential Equation
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作者 贾利群 郑世旺 张耀宇 《Journal of Beijing Institute of Technology》 EI CAS 2007年第3期256-258,共3页
An important modern method in analytical mechanics for finding the integral, which is called the field-method, is used to research the solution of a differential equation of the first order. First, by introducing an i... An important modern method in analytical mechanics for finding the integral, which is called the field-method, is used to research the solution of a differential equation of the first order. First, by introducing an intermediate variable, a more complicated differential equation of the first order can be expressed by two simple differential equations of the first order, then the field-method in analytical mechanics is introduced for solving the two differential equations of the first order. The conclusion shows that the field-method in analytical mechanics can be fully used to find the solutions of a differential equation of the first order, thus a new method for finding the solutions of the first order is provided. 展开更多
关键词 differential equation INTEGRATION field-method fundamental partial differential equation
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基于自适应神经网络的PDEs求解研究
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作者 彭杰 张玉武 《佳木斯大学学报(自然科学版)》 CAS 2024年第3期174-177,共4页
针对当前基于神经网络的PDEs求解方法效率和精度均不够理想的缺陷,研究提出一种基于改进BP神经网络(BP neural network,BPNN)的PDEs求解模型。首先,参照自适应网格法来改进神经网络结构,构建自适应神经网络,改进模型的输出精度;其次,提... 针对当前基于神经网络的PDEs求解方法效率和精度均不够理想的缺陷,研究提出一种基于改进BP神经网络(BP neural network,BPNN)的PDEs求解模型。首先,参照自适应网格法来改进神经网络结构,构建自适应神经网络,改进模型的输出精度;其次,提出一种引入Levy飞行机制和鲸鱼优化算法(Whale optimization algorithm,WOA)的改进海鸥优化算法(Improved Seagull Optimization Algorithm,ISOA)来优化BPNN,寻找BPNN的最佳参数,提高模型的性能;基于上述内容,构建基于ISOA-BPNNPDEs智能求解模型。结果显示,该模型的F1值为95.74%,准确率达到97.96%,输出误差为0.021,优于当前最先进的两种PDEs求解模型。上述内容表明,研究构建的基于ISOA-BPNNPDEs智能求解模型能够高效、准确地实现PDEs求解,为PDEs求解研究提供了新的路径。 展开更多
关键词 偏微分方程 神经网络 海鸥优化算法 鲸鱼优化
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ON THE HOLOMORPHIC SOLUTION OF NON-LINEAR TOTALLY CHARACTERISTIC EQUATIONS WITH SEVERAL SPACE VARIABLES 被引量:5
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作者 陈化 罗壮初 《Acta Mathematica Scientia》 SCIE CSCD 2002年第3期393-403,共11页
In this paper the authors study a class of non-linear singular partial differential equation in complex domain C-t x C-x(n). Under certain assumptions, they prove the existence and uniqueness of holomorphic solution n... In this paper the authors study a class of non-linear singular partial differential equation in complex domain C-t x C-x(n). Under certain assumptions, they prove the existence and uniqueness of holomorphic solution near origin of C-t x C-x(n). 展开更多
关键词 NON-LINEAR singular partial differential equation holomorphic solution
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RANDOM ATTRACTORS FOR A STOCHASTIC HYDRODYNAMICAL EQUATION IN HEISENBERG PARAMAGNET 被引量:4
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作者 郭柏灵 郭春晓 蒲学科 《Acta Mathematica Scientia》 SCIE CSCD 2011年第2期529-540,共12页
This article studies the asymptotic behaviors of the solution for a stochastic hydrodynamical equation in Heisenberg paramagnet in a two-dimensional periodic domain. We obtain the existence of random attractors in H1.
关键词 Stochastic partial differential equations Heisenberg paramagnet Randomattractor
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