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Numerical Algorithms for Solving One Type of Singular Integro-Differential Equation Containing Derivatives of the Time Delay States 被引量:1
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作者 Shihchung Chiang Terry L. Herdman 《Applied Mathematics》 2015年第8期1294-1301,共8页
This study presents numerical algorithms for solving a class of equations that partly consists of derivatives of the unknown state at previous certain times, as well as an integro-differential term containing a weakly... This study presents numerical algorithms for solving a class of equations that partly consists of derivatives of the unknown state at previous certain times, as well as an integro-differential term containing a weakly singular kernel. These equations are types of integro-differential equation of the second kind and were originally obtained from an aeroelasticity problem. One of the main contributions of this study is to propose numerical algorithms that do not involve transforming the original equation into the corresponding Volterra equation, but still enable the numerical solution of the original equation to be determined. The feasibility of the proposed numerical algorithm is demonstrated by applying examples in measuring the maximum errors with exact solutions at every computed nodes and calculating the corresponding numerical rates of convergence thereafter. 展开更多
关键词 Integro-differential equation of the Second KIND WEAKLY SINGULAR KERNEL Numerical algorithms Rates of Convergence
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Modified Algorithm for Solving Linear Integro-Differential Equations of the Second Kind
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作者 M. Al-Towaiq Ahmed Kasasbeh 《American Journal of Computational Mathematics》 2017年第2期157-165,共9页
In this paper, a modified algorithm is proposed for solving linear integro-differential equations of the second kind. The main idea is based on applying Romberg extrapolation algorithm (REA), on Trapezoidal rule. In a... In this paper, a modified algorithm is proposed for solving linear integro-differential equations of the second kind. The main idea is based on applying Romberg extrapolation algorithm (REA), on Trapezoidal rule. In accordance with the computational perspective, the comparison has shown that Adomian decomposition approach is more effective to be utilized. The numerical results show that the modified algorithm has been successfully applied to the linear integro-differential equations and the comparisons with some existing methods appeared in the literature reveal that the modified algorithm is more accurate and convenient. 展开更多
关键词 algorithm Integro-differential equationS Trapezoidal RULE Romberg EXTRAPOLATION
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Solving Ordinary Differential Equations with Evolutionary Algorithms 被引量:1
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作者 Bakre Omolara Fatimah Wusu Ashiribo Senapon Akanbi Moses Adebowale 《Open Journal of Optimization》 2015年第3期69-73,共5页
In this paper, the authors show that the general linear second order ordinary Differential Equation can be formulated as an optimization problem and that evolutionary algorithms for solving optimization problems can a... In this paper, the authors show that the general linear second order ordinary Differential Equation can be formulated as an optimization problem and that evolutionary algorithms for solving optimization problems can also be adapted for solving the formulated problem. The authors propose a polynomial based scheme for achieving the above objectives. The coefficients of the proposed scheme are approximated by an evolutionary algorithm known as Differential Evolution (DE). Numerical examples with good results show the accuracy of the proposed method compared with some existing methods. 展开更多
关键词 EVOLUTIONARY algorithm differential equationS differential EVOLUTION Optimization
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TWO TYPES OF NEW ALGORITHMS FOR FINDING EXPLICIT ANALYTICAL SOLUTIONS OF NONLINEAR DIFFERENTIAL EQUATIONS
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作者 张鸿庆 闫振亚 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第12期1423-1431,共9页
The idea of AC = BD was applied to solve the nonlinear differential equations. Suppose that Au = 0 is a given equation to he solved and Dv = 0 is an equation to be easily solved. If the transformation u = Cv is obtain... The idea of AC = BD was applied to solve the nonlinear differential equations. Suppose that Au = 0 is a given equation to he solved and Dv = 0 is an equation to be easily solved. If the transformation u = Cv is obtained so that v satisfies Dv = 0, then the solutions for Au = 0 can be found. In order to illustrate this approach, several examples about the transformation C are given. 展开更多
关键词 nonlinear differential equations transformation algorithm analytical solution
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An Easy Algorithm for Solving Radiative Transfer Equation in Clear Atmosphere 被引量:1
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作者 杨景梅 邱金桓 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1992年第4期483-490,共8页
An accurate and rapid method for solving radiative transfer equation is presented in this paper. According to the fact that the multiple scattering component of radiance is less sensitive to the error of phase functio... An accurate and rapid method for solving radiative transfer equation is presented in this paper. According to the fact that the multiple scattering component of radiance is less sensitive to the error of phase function than the single scattering component is,we calculate the multiple scattering component by using delta-Eddington approximation and the single scattering component by solving radiative transfer equation. On the ground, when multiple sattering component is small, for example, when the total optical depth T is small, the accurate radiance can be obtained with this method. For the need of the space remote sensing, the upward radiance at the top of the atmosphere is mainly studied, and an approximate expression is presented to correct the multiple scattering component. Compared with the more precise Gauss-Seidel method.the results from this method show an accuracy of better than 10% when zenith angle 0 < 50 掳 and T < 1. The computational speed of this method is, however, much faster than that of Gauss-Seidel method. 展开更多
关键词 An Easy algorithm for solving Radiative Transfer equation in Clear Atmosphere
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Furnace Temperature Curve Optimization Model Based on Differential Evolution Algorithm
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作者 Yiming Cheng 《Journal of Electronic Research and Application》 2024年第4期64-80,共17页
When soldering electronic components onto circuit boards,the temperature curves of the reflow ovens across different zones and the conveyor belt speed significantly influence the product quality.This study focuses on ... When soldering electronic components onto circuit boards,the temperature curves of the reflow ovens across different zones and the conveyor belt speed significantly influence the product quality.This study focuses on optimizing the furnace temperature curve under varying settings of reflow oven zone temperatures and conveyor belt speeds.To address this,the research sequentially develops a heat transfer model for reflow soldering,an optimization model for reflow furnace conditions using the differential evolution algorithm,and an evaluation and decision model combining the differential evolution algorithm with the Technique for Order Preference by Similarity to Ideal Solution(TOPSIS)method.This approach aims to determine the optimal furnace temperature curve,zone temperatures of the reflow oven,and the conveyor belt speed. 展开更多
关键词 Furnace temperature curve Difference equations differential evolution algorithms TOPSIS methods
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Numerical Solution of Differential Equations by Direct Taylor Expansion
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作者 Pirooz Mohazzabi Jennifer L. Becker 《Journal of Applied Mathematics and Physics》 2017年第3期623-630,共8页
A variation of the direct Taylor expansion algorithm is suggested and applied to several linear and nonlinear differential equations of interest in physics and engineering, and the results are compared with those obta... A variation of the direct Taylor expansion algorithm is suggested and applied to several linear and nonlinear differential equations of interest in physics and engineering, and the results are compared with those obtained from other algorithms. It is shown that the suggested algorithm competes strongly with other existing algorithms, both in accuracy and ease of application, while demanding a shorter computation time. 展开更多
关键词 TAYLOR Series EXPANSION algorithm NUMERICAL Solution differential equationS
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Transmission Lines Distance Protection Using Differential Equation Algorithm and Hilbert-Huang Transform
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作者 Xingmao Liu Zhengyou He 《Journal of Power and Energy Engineering》 2014年第4期616-623,共8页
This paper proposed the scheme of transmission lines distance protection based on differential equation algorithms (DEA) and Hilbert-Huang transform (HHT). The measured impedance based on EDA is affected by various fa... This paper proposed the scheme of transmission lines distance protection based on differential equation algorithms (DEA) and Hilbert-Huang transform (HHT). The measured impedance based on EDA is affected by various factors, such as the distributed capacitance, the transient response characteristics of current transformer and voltage transformer, etc. In order to overcome this problem, the proposed scheme applies HHT to improve the apparent impedance estimated by DEA. Empirical mode decomposition (EMD) is used to decompose the data set from DEA into the intrinsic mode functions (IMF) and the residue. This residue has monotonic trend and is used to evaluate the impedance of faulty line. Simulation results show that the proposed scheme improves significantly the accuracy of the estimated impedance. 展开更多
关键词 Hilbert-Huang TRANSFORM differential equation algorithm DISTANCE PROTECTION Transmission LINES
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Discretized Multisplitting AOR Waveform Relaxation Algorithms for Initial Value Problem of Systems of ODEs
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作者 谷同祥 李文强 《Chinese Quarterly Journal of Mathematics》 CSCD 1997年第4期27-35, ,共9页
The multisplitting algorithm for solving large systems of ordinary differential equations on parallel computers was introduced by Jeltsch and Pohl in [1]. On fixed time intervals conver gence results could be derived ... The multisplitting algorithm for solving large systems of ordinary differential equations on parallel computers was introduced by Jeltsch and Pohl in [1]. On fixed time intervals conver gence results could be derived if the subsystems are solving exactly.Firstly,in theis paper,we deal with an extension of the waveform relaxation algorithm by us ing multisplittin AOR method based on an overlapping block decomposition. We restricted our selves to equidistant timepoints and dealed with the case that an implicit integration method was used to solve the subsystems numerically in parallel. Then we have proved convergence of multi splitting AOR waveform relaxation algorithm on a fixed window containing a finite number of timepoints. 展开更多
关键词 systems of ordinary differential equations initial value problems multisplitting algorithm AOR method waveform relaxation algorithm
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Symmetry Classification of Partial Differential Equations Based on Wu's Method
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作者 TIAN Yi WAN Jianxiong 《Journal of Donghua University(English Edition)》 CAS 2021年第2期187-192,共6页
Lie algorithm combined with differential form Wu's method is used to complete the symmetry classification of partial differential equations(PDEs)containing arbitrary parameter.This process can be reduced to solve ... Lie algorithm combined with differential form Wu's method is used to complete the symmetry classification of partial differential equations(PDEs)containing arbitrary parameter.This process can be reduced to solve a large system of determining equations,which seems rather difficult to solve,then the differential form Wu's method is used to decompose the determining equations into a series of equations,which are easy to solve.To illustrate the usefulness of this method,we apply it to some test problems,and the results show the performance of the present work. 展开更多
关键词 Lie algorithm differential form Wu's method determining equation symmetry classification partial differential equation(PDE)
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Vibration mechanism analysis and algorithm optimization of contactor contact system
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作者 HUANG Kepeng WANG Fazhan +2 位作者 ZHAO Mingji GUO Baoliang OU Daquan 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2021年第4期396-404,共9页
In order to solve the problem of vibration bounce caused by the contact between moving and stationary contacts in the process of switching on,two-degree-of-freedom motion differential equation of the contact system is... In order to solve the problem of vibration bounce caused by the contact between moving and stationary contacts in the process of switching on,two-degree-of-freedom motion differential equation of the contact system is established.Genetic algorithm is used to optimize the pull in process of AC contactor.The whole process of contact bounce was observed and analyzed by high-speed photography experiment.The theory and experimental results were very similar.The iron core has collided before the contact is separated,which further aggravates the contact bounce.When the iron core bounces collided again,the bounce of the contact was not affected.During the operation of the contactor,the movement of the moving iron core will cause slight vibration of the system.The contact bounce time and the maximum amplitude are reduced.The research results provide a theoretical basis for further control and reduction of contact bounce. 展开更多
关键词 electrical switch contact bounce two-degree-of-freedom motion differential equation algorithm optimization high-speed photography
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EXACT ANALYTIC METHOD FG(?) SOLVING VARIABLE COEFFICIENT DIFFERENTIAL EQUATION
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作者 纪振义 叶开源 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第10期885-896,共12页
Many engineering problems can be reduced to the solution of a variable coefficient differential equation. In this paper, the exact analytic method is suggested to solve variable coefficient differential equations unde... Many engineering problems can be reduced to the solution of a variable coefficient differential equation. In this paper, the exact analytic method is suggested to solve variable coefficient differential equations under arbitrary boundary condition. By this method, the general computation formal is obtained. Its convergence in proved. We can get analytic expressions which converge to exact solution and its higher order derivatives uniformy Four numerical examples are given, which indicate that satisfactory results can he obtanedby this method. 展开更多
关键词 solving VARIABLE COEFFICIENT differential equation EXACT ANALYTIC METHOD FG
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Optimality Conditions and Algorithms for Direct Optimizing the Partial Differential Equations
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作者 Victor K. Tolstykh 《Engineering(科研)》 2012年第7期390-393,共4页
New form of necessary conditions for optimality (NCO) is considered. They can be useful for design the direct infinite- dimensional optimization algorithms for systems described by partial differential equations (PDE)... New form of necessary conditions for optimality (NCO) is considered. They can be useful for design the direct infinite- dimensional optimization algorithms for systems described by partial differential equations (PDE). Appropriate algo-rithms for unconstrained minimizing a functional are considered and tested. To construct the algorithms, new form of NCO is used. Such approach demonstrates fast uniform convergence at optimal solution in infinite-dimensional space. 展开更多
关键词 Optimization GRADIENT Necessary Conditions for OPTIMALITY Partial differential equationS Infinite-Dimensional algorithms
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A Third-Order Accurate Wave Propagation Algorithm for Hyperbolic Partial Differential Equations
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作者 Christiane Helzel 《Communications on Applied Mathematics and Computation》 2020年第3期403-427,共25页
We extend LeVeque's wave propagation algorithm,a widely used finite volume method for hyperbolic partial differential equations,to a third-order accurate method.The resulting scheme shares main properties with the... We extend LeVeque's wave propagation algorithm,a widely used finite volume method for hyperbolic partial differential equations,to a third-order accurate method.The resulting scheme shares main properties with the original method,i.e.,it is based on a wave decomposition at grid cell interfaces,it can be used to approximate hyperbolic problems in divergence form as well as in quasilinear form and limiting is introduced in the form of a wave limiter. 展开更多
关键词 Wave propagation algorithm Hyperbolic partial differential equations Third-order accuracy
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Determination of a Numerical Analysis Algorithm for the Regulation of Blood Sugar in Diabetics
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作者 Kolo Silue Hyacinthe Kouassi Konan +1 位作者 Mamadou Coulibaly Olivier Asseu 《Open Journal of Applied Sciences》 2021年第8期908-928,共21页
Acceptable glycemic control when examining the effects of meals was </span></span><span><span><span style="font-family:"">achieved when combining basal insulin therapy and ... Acceptable glycemic control when examining the effects of meals was </span></span><span><span><span style="font-family:"">achieved when combining basal insulin therapy and high concentration insulin injection before a meal, when using a PID controller (Proportionality, Integrity and Derivative actions) alone, when using a PID controller with basal insulin therapy and when combining the three methods of insulin delivery. Naturally, a type 1 diabetic must inject himself with insulin in well-measured doses. Thus, the management and control of diabetes become a complex task when one must be considered the disturbance due to nutrition and sports activity. This concern has been at the center of much research through different approaches through mathematical methods and Artificial Intelligence methods. This article simulates a physiological model of glycemic control in type 1 diabetics by a PID regulatory mechanism, in the context of disturbances caused by the patient’s meals and athletic activity. 展开更多
关键词 system of differential equation solving algorithm Physiological Model Simulation Glucose Concentrations DIABETIC Disturbance Function PID Controller
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Coupled Cross-correlation Neural Network Algorithm for Principal Singular Triplet Extraction of a Cross-covariance Matrix 被引量:2
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作者 Xiaowei Feng Xiangyu Kong Hongguang Ma 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2016年第2期149-156,共8页
This paper proposes a novel coupled neural network learning algorithm to extract the principal singular triplet (PST) of a cross-correlation matrix between two high-dimensional data streams. We firstly introduce a nov... This paper proposes a novel coupled neural network learning algorithm to extract the principal singular triplet (PST) of a cross-correlation matrix between two high-dimensional data streams. We firstly introduce a novel information criterion (NIC), in which the stationary points are singular triplet of the crosscorrelation matrix. Then, based on Newton's method, we obtain a coupled system of ordinary differential equations (ODEs) from the NIC. The ODEs have the same equilibria as the gradient of NIC, however, only the first PST of the system is stable (which is also the desired solution), and all others are (unstable) saddle points. Based on the system, we finally obtain a fast and stable algorithm for PST extraction. The proposed algorithm can solve the speed-stability problem that plagues most noncoupled learning rules. Moreover, the proposed algorithm can also be used to extract multiple PSTs effectively by using sequential method. © 2014 Chinese Association of Automation. 展开更多
关键词 Clustering algorithms Covariance matrix Data mining differential equations EXTRACTION Learning algorithms Negative impedance converters Newton Raphson method Ordinary differential equations Singular value decomposition
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Unsupervised neural network model optimized with evolutionary computations for solving variants of nonlinear MHD Jeffery-Hamel problem 被引量:1
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作者 M.A.Z.RAJA R.SAMAR +1 位作者 T.HAROON S.M.SHAH 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2015年第12期1611-1638,共28页
A heuristic technique is developed for a nonlinear magnetohydrodynamics (MHD) Jeffery-Hamel problem with the help of the feed-forward artificial neural net- work (ANN) optimized with the genetic algorithm (GA) a... A heuristic technique is developed for a nonlinear magnetohydrodynamics (MHD) Jeffery-Hamel problem with the help of the feed-forward artificial neural net- work (ANN) optimized with the genetic algorithm (GA) and the sequential quadratic programming (SQP) method. The twodimensional (2D) MHD Jeffery-Hamel problem is transformed into a higher order boundary value problem (BVP) of ordinary differential equations (ODEs). The mathematical model of the transformed BVP is formulated with the ANN in an unsupervised manner. The training of the weights of the ANN is carried out with the evolutionary calculation based on the GA hybridized with the SQP method for the rapid local convergence. The proposed scheme is evaluated on the variants of the Jeffery-Hamel flow by varying the Reynold number, the Hartmann number, and the an- gles of the walls. A large number of simulations are performed with an extensive analysis to validate the accuracy, convergence, and effectiveness of the scheme. The comparison of the standard numerical solution and the analytic solution establishes the correctness of the proposed designed methodologies. 展开更多
关键词 Jeffery-Hamel problem neural network genetic algorithm (GA) nonlinear ordinary differential equation (ODE) hybrid technique sequential quadratic programming
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Quantum algorithms for uncertainty quantification:Applications to partial differential equations
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作者 Francoise Golse Shi Jin Nana Liu 《Science China(Physics,Mechanics & Astronomy)》 2025年第10期34-55,共22页
Most problems in uncertainty quantification,despite their ubiquitousness in scientific computing,applied mathematics and data science,remain formidable on a classical computer.For uncertainties that arise in partial d... Most problems in uncertainty quantification,despite their ubiquitousness in scientific computing,applied mathematics and data science,remain formidable on a classical computer.For uncertainties that arise in partial differential equations(PDEs),large numbers M>>1 of samples are required to obtain accurate ensemble averages.This usually involves solving the PDE M times.In addition,to characterise the stochasticity in a PDE,the dimension L of the random input variables is high in most cases,and classical algorithms suffer from the curse-of-dimensionality.We propose new quantum algorithms for PDEs with uncertain coefficients that are more efficient in M and L in various important regimes,compared to their classical counterparts.We introduce transformations that convert the original d-dimensional equation(with uncertain coefficients)into d+L(for dissipative equations)or d+2L(for wave type equations)dimensional equations(with certain coefficients)in which the uncertainties appear only in the initial data.These transformations also allow one to superimpose the M different initial data,so the computational cost for the quantum algorithm to obtain the ensemble average from M different samples is independent of M,while also showing potential advantage in d,L and precisionεin computing ensemble averaged solutions or physical observables. 展开更多
关键词 partial differential equations quantum algorithm uncertainty quantification
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PGOPO Approach to Design Linear Servomechanism of Time-Varying Systems with Time-Delay
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作者 吴斌 程鹏 钟宜生 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2001年第2期88-93,共6页
Based on a new linear, continuous and bounded operator (PGOPO), a more effective approach and optimal control algorithm than by the block-pulse functions and Walsh functions to design the linear servomechanism of time... Based on a new linear, continuous and bounded operator (PGOPO), a more effective approach and optimal control algorithm than by the block-pulse functions and Walsh functions to design the linear servomechanism of time-varying systems with time-delay is proposed in the paper. By means of the operator, the differential equation is transferred to a more explicit algebraic form which is much easier than the numerical integration of nonlinear TPBVP derived from Pantryagin's maximum principle method. Furthermore, the method is established strictly based on the theory of convergence in the mean square and it is convenient and simple in computation. So the method can be applied to industry control and aeronautics and astronautics field which is frequently mixed with time varying and time delay. Some illustrative numerical examples are interpreted to support the technique. 展开更多
关键词 algorithmS Convergence of numerical methods differential equations Mathematical operators POLYNOMIALS Time varying systems Walsh transforms
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Parallel Evolutionary Modeling for Nonlinear Ordinary Differential Equations
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作者 Kang Zhuo Liu Pu Kang Li-shan 《Wuhan University Journal of Natural Sciences》 EI CAS 2001年第3期659-664,共6页
We introduce a new parallel evolutionary algorithm in modeling dynamic systems by nonlinear higher-order ordinary differential equations (NHODEs). The NHODEs models are much more universal than the traditional linear ... We introduce a new parallel evolutionary algorithm in modeling dynamic systems by nonlinear higher-order ordinary differential equations (NHODEs). The NHODEs models are much more universal than the traditional linear models. In order to accelerate the modeling process, we propose and realize a parallel evolutionary algorithm using distributed CORBA object on the heterogeneous networking. Some numerical experiments show that the new algorithm is feasible and efficient. 展开更多
关键词 parallel evolutionary algorithm higher-order ordinary differential equation CORBA
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