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Novel Investigation of Stochastic Fractional Differential Equations Measles Model via the White Noise and Global Derivative Operator Depending on Mittag-Leffler Kernel 被引量:1
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作者 Saima Rashid Fahd Jarad 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2289-2327,共39页
Because of the features involved with their varied kernels,differential operators relying on convolution formulations have been acknowledged as effective mathematical resources for modeling real-world issues.In this p... Because of the features involved with their varied kernels,differential operators relying on convolution formulations have been acknowledged as effective mathematical resources for modeling real-world issues.In this paper,we constructed a stochastic fractional framework of measles spreading mechanisms with dual medication immunization considering the exponential decay and Mittag-Leffler kernels.In this approach,the overall population was separated into five cohorts.Furthermore,the descriptive behavior of the system was investigated,including prerequisites for the positivity of solutions,invariant domain of the solution,presence and stability of equilibrium points,and sensitivity analysis.We included a stochastic element in every cohort and employed linear growth and Lipschitz criteria to show the existence and uniqueness of solutions.Several numerical simulations for various fractional orders and randomization intensities are illustrated. 展开更多
关键词 Measles epidemic model Atangana-Baleanu Caputo-Fabrizio differential operators existence and uniqueness qualitative analysis Newton interpolating polynomial
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A Coupled Thermomechanical Crack Propagation Behavior of Brittle Materials by Peridynamic Differential Operator
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作者 Tianyi Li Xin Gu Qing Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期339-361,共23页
This study proposes a comprehensive,coupled thermomechanical model that replaces local spatial derivatives in classical differential thermomechanical equations with nonlocal integral forms derived from the peridynamic... This study proposes a comprehensive,coupled thermomechanical model that replaces local spatial derivatives in classical differential thermomechanical equations with nonlocal integral forms derived from the peridynamic differential operator(PDDO),eliminating the need for calibration procedures.The model employs a multi-rate explicit time integration scheme to handle varying time scales in multi-physics systems.Through simulations conducted on granite and ceramic materials,this model demonstrates its effectiveness.It successfully simulates thermal damage behavior in granite arising from incompatible mineral expansion and accurately calculates thermal crack propagation in ceramic slabs during quenching.To account for material heterogeneity,the model utilizes the Shuffle algorithm andWeibull distribution,yielding results that align with numerical simulations and experimental observations.This coupled thermomechanical model shows great promise for analyzing intricate thermomechanical phenomena in brittle materials. 展开更多
关键词 Peridynamic differential operator thermomechanical coupling HETEROGENEITY numerical simulation
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Euler’s First-Order Explicit Method–Peridynamic Differential Operator for Solving Population Balance Equations of the Crystallization Process
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作者 Chunlei Ruan Cengceng Dong +2 位作者 Kunfeng Liang Zhijun Liu Xinru Bao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期3033-3049,共17页
Using Euler’s first-order explicit(EE)method and the peridynamic differential operator(PDDO)to discretize the time and internal crystal-size derivatives,respectively,the Euler’s first-order explicit method–peridyna... Using Euler’s first-order explicit(EE)method and the peridynamic differential operator(PDDO)to discretize the time and internal crystal-size derivatives,respectively,the Euler’s first-order explicit method–peridynamic differential operator(EE–PDDO)was obtained for solving the one-dimensional population balance equation in crystallization.Four different conditions during crystallization were studied:size-independent growth,sizedependent growth in a batch process,nucleation and size-independent growth,and nucleation and size-dependent growth in a continuous process.The high accuracy of the EE–PDDO method was confirmed by comparing it with the numerical results obtained using the second-order upwind and HR-van methods.The method is characterized by non-oscillation and high accuracy,especially in the discontinuous and sharp crystal size distribution.The stability of the EE–PDDO method,choice of weight function in the PDDO method,and optimal time step are also discussed. 展开更多
关键词 Population balance equation CRYSTALLIZATION peridynamic differential operator Euler’s first-order explicit method
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Operational optimization of copper flotation process based on the weighted Gaussian process regression and index-oriented adaptive differential evolution algorithm
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作者 Zhiqiang Wang Dakuo He Haotian Nie 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期167-179,共13页
Concentrate copper grade(CCG)is one of the important production indicators of copper flotation processes,and keeping the CCG at the set value is of great significance to the economic benefit of copper flotation indust... Concentrate copper grade(CCG)is one of the important production indicators of copper flotation processes,and keeping the CCG at the set value is of great significance to the economic benefit of copper flotation industrial processes.This paper addresses the fluctuation problem of CCG through an operational optimization method.Firstly,a density-based affinity propagationalgorithm is proposed so that more ideal working condition categories can be obtained for the complex raw ore properties.Next,a Bayesian network(BN)is applied to explore the relationship between the operational variables and the CCG.Based on the analysis results of BN,a weighted Gaussian process regression model is constructed to predict the CCG that a higher prediction accuracy can be obtained.To ensure the predicted CCG is close to the set value with a smaller magnitude of the operation adjustments and a smaller uncertainty of the prediction results,an index-oriented adaptive differential evolution(IOADE)algorithm is proposed,and the convergence performance of IOADE is superior to the traditional differential evolution and adaptive differential evolution methods.Finally,the effectiveness and feasibility of the proposed methods are verified by the experiments on a copper flotation industrial process. 展开更多
关键词 Weighted Gaussian process regression Index-oriented adaptive differential evolution operational optimization Copper flotation process
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Inverse Differential Operators in Time and Space
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作者 Edwin Eugene Klingman 《Journal of Applied Mathematics and Physics》 2023年第12期3789-3799,共11页
When one function is defined as a differential operation on another function, it’s often desirable to invert the definition, to effectively “undo” the differentiation. A Green’s function approach is often used to ... When one function is defined as a differential operation on another function, it’s often desirable to invert the definition, to effectively “undo” the differentiation. A Green’s function approach is often used to accomplish this, but variations on this theme exist, and we examine a few such variations. The mathematical analysis of  is sought in the form  if such an inverse operator exists, but physics is defined by both mathematical formula and ontological formalism, as I show for an example based on the Dirac equation. Finally, I contrast these “standard” approaches with a novel exact inverse operator for field equations. 展开更多
关键词 Matrix-Inverse differential operators Green’s Functions Dirac’s Equation Wave Equations Inverse Curl operator
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Boundedness for Multilinear Operators of Pseudo-Differential Operators
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作者 Jiasheng Zeng Rongping Chen +2 位作者 Jiangang Liu Xiaojing Wang Chunsheng Liu 《Advances in Pure Mathematics》 2023年第7期449-462,共14页
In this paper, we establish a sharp function estimate for the multilinear integral operators associated to the pseudo-differential operators. As the application, we obtain the L<sup>p</sup> (1 p norm ... In this paper, we establish a sharp function estimate for the multilinear integral operators associated to the pseudo-differential operators. As the application, we obtain the L<sup>p</sup> (1 p norm inequalities for the multilinear operators. 展开更多
关键词 Multilinear operator Pseudo-differential operator Sharp Function Estimate BMO
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A MULTIPLE q-EXPONENTIAL DIFFERENTIAL OPERATIONAL IDENTITY
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作者 刘治国 《Acta Mathematica Scientia》 SCIE CSCD 2023年第6期2449-2470,共22页
Using Hartogs’fundamental theorem for analytic functions in several complex variables and q-partial differential equations,we establish a multiple q-exponential differential formula for analytic functions in several ... Using Hartogs’fundamental theorem for analytic functions in several complex variables and q-partial differential equations,we establish a multiple q-exponential differential formula for analytic functions in several variables.With this identity,we give new proofs of a variety of important classical formulas including Bailey’s 6ψ6 series summation formula and the Atakishiyev integral.A new transformation formula for a double q-series with several interesting special cases is given.A new transformation formula for a 3ψ3 series is proved. 展开更多
关键词 q-hypergeometric series q-exponential differential operator Bailey's 6b6 summation double q-hypergeometric series q-partial differential equation
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Representations of Inverse Covariances by Differential Operators 被引量:3
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作者 Qin XU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2005年第2期181-198,共18页
In the cost function of three- or four-dimensional variational dataassimilation, each term is weighted by the inverse of its associated error covariance matrix and thebackground error covariance matrix is usually much... In the cost function of three- or four-dimensional variational dataassimilation, each term is weighted by the inverse of its associated error covariance matrix and thebackground error covariance matrix is usually much larger than the other covariance matrices.Although the background error covariances are traditionally normalized and parameterized by simplesmooth homogeneous correlation functions, the covariance matrices constructed from these correlationfunctions are often too large to be inverted or even manipulated. It is thus desirable to finddirect representations of the inverses of background error correlations. This problem is studied inthis paper. In particular, it is shown that the background term can be written into ∫ dx∣Dυ(x)∣~2, that is, a squared 1/2 norm of a vector differential operator D, called theD-operator, applied to the field of analysis increment υ(x). For autoregressive correlationfunctions, the D-operators are of finite orders. For Gaussian correlation functions, the D-operatorsare of infinite order. For practical applications, the Gaussian D-operators must be truncated tofinite orders. The truncation errors are found to be small even when the Gaussian D-operators aretruncated to low orders. With a truncated D-operator, the background term can be easily constructedwith neither inversion nor direct calculation of the covariance matrix. D-operators are also derivedfor non-Gaussian correlations and transformed into non-isotropic forms. 展开更多
关键词 differential operator inverse background covariance data assimilation
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Spectrum of a class of fourth order left-definite differential operators 被引量:2
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作者 GAO Yun-lan SUN Jiong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第1期51-56,共6页
The spectrum of a class of fourth order left-definite differential operators is studied. By using the theory of indefinite differential operators in Krein space and the relationship between left-definite and right-def... The spectrum of a class of fourth order left-definite differential operators is studied. By using the theory of indefinite differential operators in Krein space and the relationship between left-definite and right-definite operators, the following conclusions are obtained: if a fourth order differential operator with a self-adjoint boundary condition that is left-definite and right-indefinite, then all its eigenvalues are real, and there exist countably infinitely many positive and negative eigenvalues which are unbounded from below and above, have no finite cluster point and can be indexed to satisfy the inequality …≤λ-2≤λ-1≤λ-0〈0〈λ0≤λ1≤λ2≤… 展开更多
关键词 left-definite differential operator right-definite differential operator Krein space spectrum eigenvalue.
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Some Basic Properties for Certain Classes of p-valent Analytic Functions Using Differential Operator 被引量:1
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作者 ZHANG Hai- Yan TANG Huo +1 位作者 LI Shu-Hai MA Li-Na 《Chinese Quarterly Journal of Mathematics》 2018年第2期132-139,共8页
In this paper, we introduce new subclasses of p-valent analytic functions defined by using differential operator in the open unit disc. We study coefficient inequality, distortion theorem, radius of close to-convexity... In this paper, we introduce new subclasses of p-valent analytic functions defined by using differential operator in the open unit disc. We study coefficient inequality, distortion theorem, radius of close to-convexity, starlikeness and convexity, extreme points and integral operator for functions in these new subclasses. 展开更多
关键词 p-valent functions differential operator Coefficient inequality Distortion theorem RADIUS
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Relationships among Three Multiplicities of a Differential Operator’s Eigenvalue 被引量:1
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作者 Shouzhong Fu Zhong Wang 《Applied Mathematics》 2014年第15期2185-2194,共10页
In this paper, the algebraic, geometric and analytic multiplicities of an eigenvalue for linear differential operators are defined and classified. The relationships among three multiplicities of an eigenvalue of the l... In this paper, the algebraic, geometric and analytic multiplicities of an eigenvalue for linear differential operators are defined and classified. The relationships among three multiplicities of an eigenvalue of the linear differential operator are given, and a fundamental fact that the algebraic, geometric and analytic multiplicities for any eigenvalue of self-adjoint differential operators are equal is proven. 展开更多
关键词 differential operatorS EIGENVALUE ALGEBRAIC MULTIPLICITIES Geometric MULTIPLICITIES ANALYTIC MULTIPLICITIES
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LEIBNIZ′FORMULA OF GENERALIZED DIFFERENCE WITH RESPECT TO A CLASS OF DIFFERENTIAL OPERATORS AND RECURRENCE FORMULA OF THEIR GREEN′S FUNCTION 被引量:1
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作者 许跃生 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1984年第3期1359-1364,共6页
In this paper, Leibniz' formula of generalized divided difference with respect to a class of differential operators whose basic sets of solutions have power form, is considered. The recurrence formula of Green fun... In this paper, Leibniz' formula of generalized divided difference with respect to a class of differential operators whose basic sets of solutions have power form, is considered. The recurrence formula of Green function about the operators is also given. 展开更多
关键词 LEIBNIZ S FUNCTION FORMULA OF GENERALIZED DIFFERENCE WITH RESPECT TO A CLASS OF differential operatorS AND RECURRENCE FORMULA OF THEIR GREEN
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FINITE ELEMENT APPROXIMATION OF AN INTEGRO-DIFFERENTIAL OPERATOR 被引量:3
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作者 丁夏畦 罗佩珠 《Acta Mathematica Scientia》 SCIE CSCD 2009年第6期1767-1776,共10页
This paper deals with the finite element approximation of an integro-differential equation related with Riemann zeta-function.
关键词 finite element integro-differential operator Riemann zeta-function
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RELATIONS OF DERIVATIVE ALGEBRA AND RING OF DIFFERENTIAL OPERATORS IN CHARACTERISTIC p>0
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作者 ZHANG Jiang-feng (张江峰) 《Journal of Shanghai Jiaotong university(Science)》 EI 2002年第1期110-114,共5页
Let K be a field of characteristic p>0 . We prove that the derivative algebra of K[x 1,…,x n] is a proer subring of the ring of differential operators of K[x 1,…,x n] . A concrete example is given to show that th... Let K be a field of characteristic p>0 . We prove that the derivative algebra of K[x 1,…,x n] is a proer subring of the ring of differential operators of K[x 1,…,x n] . A concrete example is given to show that there is a differential operator of order p that does not belong to the derivative algebra. By these results, is follows that the derivative algebra is Morita equivalent to K[x p 1,…,x p n] , and hence its global homological dimension, Krull dimension, K 0 group and some other properties are got. 展开更多
关键词 DERIVATIVE ALGEBRA RING of differential operatorS MORITA EQUIVALENCE
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General Formulae for Two Pseudo-differential Operator 被引量:3
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作者 ZHANG Da-Jun WU Hua +1 位作者 DENG Shu-Fang BI Jin-Bo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第6期1393-1396,共4页
在与 nonisospectral KP 和 mKP 层次有关的 Sato 理论的一些一般公式为简化计算被导出。
关键词 Sato理论 假拟微分算子 一般公式 KP mKP
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INVARIANT REPRESENTATION FOR STOCHASTIC DIFFERENTIAL OPERATOR BY BSDES WITH UNIFORMLY CONTINUOUS COEFFICIENTS AND ITS APPLICATIONS
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作者 贾广岩 张娜 《Acta Mathematica Scientia》 SCIE CSCD 2013年第5期1407-1418,共12页
In this paper, we prove that a kind of second order stochastic differential op- erator can be represented by the limit of solutions of BSDEs with uniformly continuous coefficients. This result is a generalization of t... In this paper, we prove that a kind of second order stochastic differential op- erator can be represented by the limit of solutions of BSDEs with uniformly continuous coefficients. This result is a generalization of the representation for the uniformly continuous generator. With the help of this representation, we obtain the corresponding converse comparison theorem for the BSDEs with uniformly continuous coefficients, and get some equivalent relationships between the properties of the generator g and the associated solutions of BSDEs. Moreover, we give a new proof about g-convexity. 展开更多
关键词 backward stochastic differential equations stochastic differential operators representation theorems converse comparison theorem
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DIFFERENTIAL OPERATORS OF INFINITE ORDER IN THE SPACE OF RAPIDLY DECREASING SEQUENCES
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作者 M.MALDONADO J.PRADA M.J.SENOSIAIN 《Acta Mathematica Scientia》 SCIE CSCD 2016年第2期325-333,共9页
We consider the space of rapidly decreasing sequences s and the derivative operator D defined on it. The object of this article is to study the equivalence of a differential operator of infinite order; that is φ(D)... We consider the space of rapidly decreasing sequences s and the derivative operator D defined on it. The object of this article is to study the equivalence of a differential operator of infinite order; that is φ(D) =^∞∑k=0φkD^k.φk constant numbers an a power of D.Dn, meaning, is there a isomorphism X (from s onto s) such that Xφ(D) = D^nX?. We prove that if φ(D) is equivalent to Dn, then φ(D) is of finite order, in fact a polynomial of degree n. The question of the equivalence of two differential operators of finite order in the space s is addressed too and solved completely when n = 1. 展开更多
关键词 Ordinary differential operators sequence spaces operators on function spaces
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ON A NEW CLASS OF ANALYTIC FUNCTION DERIVED BY A FRACTIONAL DIFFERENTIAL OPERATOR
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作者 Rabha W.IBRAHIM Janusz SOKóL 《Acta Mathematica Scientia》 SCIE CSCD 2014年第5期1417-1426,共10页
Making use of the fractional differential operator, we impose and study a new class of analytic functions in the unit disk (type fractional differential equation). The main object of this paper is to investigate inc... Making use of the fractional differential operator, we impose and study a new class of analytic functions in the unit disk (type fractional differential equation). The main object of this paper is to investigate inclusion relations, coefficient bound for this class. Moreover, we discuss some geometric properties of the fractional differential operator. 展开更多
关键词 analytic function fractional calculus fractional differential operator univalentfunction unit disk bounded turning function
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ENDPOINT ESTIMATES FOR THE COMMUTATOR OF PSEUDO-DIFFERENTIAL OPERATORS 被引量:1
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作者 杨杰 王宇钊 陈文艺 《Acta Mathematica Scientia》 SCIE CSCD 2014年第2期387-393,共7页
It is well known that the commutator Tb of the Calderbn-Zygmund singular integral operator is bounded on LP(Rn) for 1 〈 p 〈 +∞ if and only if b E BMO [1]. On the other hand, the commutator Tb is bounded from H1... It is well known that the commutator Tb of the Calderbn-Zygmund singular integral operator is bounded on LP(Rn) for 1 〈 p 〈 +∞ if and only if b E BMO [1]. On the other hand, the commutator Tb is bounded from H1(Rn) into L1(Rn) only if the function b is a constant [2]. In this article, we will discuss the boundedness of commutator of certain pseudo-differential operators on Hardy spaces H1. Let Tσ be the operators that its symbol is Sσ1,δ with 0 ≤δ〈 1, if b ∈ LMO∞, then, the commutator [b, Tσ] is bounded from H1(Rn) into L1(Rn) and from L∞(Rn) into BMO(Rn); If [b,Tσ] is bounded from H1(Rn) into L1(Rn) or L1(Rn) into BMO(Rn), then, b ∈ LMOtoc. 展开更多
关键词 Hardy space COMMUTATOR Pseudo-differential operator LMO space
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<i>F</i>-Multiautomata on Join Spaces Induced by Differential Operators
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作者 Rajab Ali Borzooei Hamid Reza Varasteh Abbas Hasankhani 《Applied Mathematics》 2014年第9期1386-1391,共6页
In this paper, we introduce the notion of fuzzy multiautomata and we investigate the hyperstructures induced by the linear second-order differential operators which can be used for construction of fuzzy multiautomata ... In this paper, we introduce the notion of fuzzy multiautomata and we investigate the hyperstructures induced by the linear second-order differential operators which can be used for construction of fuzzy multiautomata serving as a theoretical background for modeling of processes. 展开更多
关键词 Fuzzy Systems differential operatorS Hyperalgebraic Structures Multiautomata
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