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Simulation and comparison of several numerical algorithms for solving ballistic differential equations 被引量:3
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作者 马焱 赵捍东 +1 位作者 许金鹏 朱福林 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第1期35-39,共5页
Several numerical methods of differential equations and their applications in ballistic calculation are discussed for the purpose of simplification of the dynamic differential equations of projectile trajectory.Progra... Several numerical methods of differential equations and their applications in ballistic calculation are discussed for the purpose of simplification of the dynamic differential equations of projectile trajectory.Program simulations of Euler method,Heun method,lassic fourth-order Runge Kutta(RK4)method,ABM method and Hamming method are achieved based on Matlab.In addtion,the approximate solutions,local truncation errors and calculation time of the dynamic differential equations are obtained.By analyzing the simultaion results,the advantages and disadvantages of these methods are compared,which provides a basis for choice of ballistic calculation methods. 展开更多
关键词 classic fourth-order Runge Kutta(rk4)method ballistic calculation calculation time
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替米沙坦对慢性心房颤动患者心房肌细胞K_(Ach)的影响 被引量:1
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作者 王胜文 魏敏 +2 位作者 杜明昭 王志 邢玥 《中国老年学杂志》 CAS CSCD 北大核心 2012年第21期4644-4646,共3页
目的探讨原型长正五聚蛋白3(PTX3)在心房颤动(AF)发生和维持中的作用及机制。方法心脏手术中建立体外循环,于心脏停搏前获取右心耳100 mg,除去血液和脂肪组织。对心房分离肌细胞采用PTX3处理,用PCR法和WB法观察心房分离肌细胞KAch基因... 目的探讨原型长正五聚蛋白3(PTX3)在心房颤动(AF)发生和维持中的作用及机制。方法心脏手术中建立体外循环,于心脏停搏前获取右心耳100 mg,除去血液和脂肪组织。对心房分离肌细胞采用PTX3处理,用PCR法和WB法观察心房分离肌细胞KAch基因和蛋白的变化。结果 AF组的Kir3.4 mRNA表达、GIRK4表达及IKAch密度明显低于SR组,小剂量组的Kir3.4 mRNA、GIRK4表达及IKAch密度低于AF组,中剂量组的Kir3.4 mRNA、GIRK4表达及IKAch密度低于小剂量组,大剂量组的Kir3.4 mRNA表达、GIRK4表达及IKAch密度低于中剂量组,均有统计学差异。结论 KAch参与了AF的病理过程。PTX3通过影响慢性AF患者心房肌细胞Kir3.4 mRNA和GIRK4表达,进而使IKAch密度降低,推测其可能导致AF发生和维持。PTX3可能通过促进AF炎症反应的发生从而引起心房重构,推测炎症可能是AF发生和维持的原因。 展开更多
关键词 心房颤动 乙酰胆碱敏感钾通道 Kir3.4 G1rk4 原型长正五聚蛋白3
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求解欧式看跌期权两种数值解法的比较 被引量:1
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作者 温梦珠 张金良 《南阳师范学院学报》 CAS 2016年第12期22-25,共4页
基于有限差分法、径向基函数法和四级四阶龙格-库塔法(RK4),给出了两种求解欧式看跌期权定价问题的数值计算格式.算例计算结果显示,基于径向基函数法、四级四阶龙格-库塔法的数值计算格式精度更高.
关键词 欧式看跌期权 径向基函数法 有限差分法 rk4
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无人机仿真测试系统设计应用研究 被引量:5
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作者 吕晓林 罗存哲 《宇航计测技术》 CSCD 2011年第1期25-29,共5页
仿真测试系统可以对无人机控制规律进行有效的检测和评估,在无人机研制中起到重要作用。通过研究无人机仿真测试系统工作原理,建立了无人机动力学和运动学数学模型,采用四阶龙格-库塔法进行解算,得到了无人机位置、高度和姿态等信息,对... 仿真测试系统可以对无人机控制规律进行有效的检测和评估,在无人机研制中起到重要作用。通过研究无人机仿真测试系统工作原理,建立了无人机动力学和运动学数学模型,采用四阶龙格-库塔法进行解算,得到了无人机位置、高度和姿态等信息,对无人机飞行控制的稳定性进行有效验证和评估,并成功运用于某型无人机的研制中。 展开更多
关键词 无人机 仿真 测试 龙格-库塔法
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跳-扩散下欧式看涨期权的径向基函数法 被引量:1
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作者 温梦珠 张金良 沈琳琳 《平顶山学院学报》 2018年第2期16-21,共6页
利用径向基函数法研究了跳-扩散下欧式看涨期权定价问题.为了证实径向基函数法的有效性,分别给出了利用径向基函数法和四阶龙格-库塔法(RK4)及有限差分法和RK4求解跳-扩散下欧式看涨期权定价问题的数值计算格式.算例计算结果显示,若采... 利用径向基函数法研究了跳-扩散下欧式看涨期权定价问题.为了证实径向基函数法的有效性,分别给出了利用径向基函数法和四阶龙格-库塔法(RK4)及有限差分法和RK4求解跳-扩散下欧式看涨期权定价问题的数值计算格式.算例计算结果显示,若采用相同的数值积分法,基于径向基函数法和RK4的数值计算格式精度更高. 展开更多
关键词 跳-扩散过程 欧式看涨期权 径向基函数法 有限差分法 rk4
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Fractional Analysis of Viscous Fluid Flow with Heat and Mass Transfer Over a Flexible Rotating Disk
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作者 Muhammad Shuaib Muhammad Bilal +1 位作者 Muhammad Altaf Khan Sharaf J.Malebary 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第4期377-400,共24页
An unsteady viscous fluid flow with Dufour and Soret effect,which results in heat and mass transfer due to upward and downward motion of flexible rotating disk,has been studied.The upward or downward motion of non rot... An unsteady viscous fluid flow with Dufour and Soret effect,which results in heat and mass transfer due to upward and downward motion of flexible rotating disk,has been studied.The upward or downward motion of non rotating disk results in two dimensional flow,while the vertical action and rotation of the disk results in three dimensional flow.By using an appropriate transformation the governing equations are transformed into the system of ordinary differential equations.The system of ordinary differential equations is further converted into first order differential equation by selecting suitable variables.Then,we generalize the model by using the Caputo derivative.The numerical result for the fractional model is presented and validated with Runge Kutta order 4 method for classical case.The compared results are presented in Table and Figures.It is concluded that the fractional model is more realistic than that of classical one,because it simulates the fluid behavior at each fractional value rather than the integral values. 展开更多
关键词 Caputo derivatives similarity transformation rk4 soret effect Dufour effect
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Numerical Simulation Using GEM for the Optimization Problem as a System of FDEs
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作者 Mohamed Adel Mohamed M. Khader 《Applied Mathematics》 2017年第12期1761-1768,共8页
In this paper, we introduce a numerical treatment using generalized Euler method (GEM) for the non-linear programming problem which is governed by a system of fractional differential equations (FDEs). The appeared fra... In this paper, we introduce a numerical treatment using generalized Euler method (GEM) for the non-linear programming problem which is governed by a system of fractional differential equations (FDEs). The appeared fractional derivatives in these equations are in the Caputo sense. We compare our numerical solutions with those numerical solutions using RK4 method. The obtained numerical results of the optimization problem model show the simplicity and the efficiency of the proposed scheme. 展开更多
关键词 Nonlinear Programming PENALTY Function Dynamic SYSTEM Caputo Fractional DERIVATIVE Generalized EULER METHOD rk4 METHOD
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Solution of Modified Equations of Emden-Type by Differential Transform Method
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作者 Supriya Mukherjee Banamali Roy Pratik Kumar Chatterjee 《Journal of Modern Physics》 2011年第6期559-563,共5页
In this paper the Modified Equations of Emden type (MEE), χ+αχχ+βχ 3 is solved numerically by the differential transform method. This technique doesn’t require any discretization, linearization or small perturb... In this paper the Modified Equations of Emden type (MEE), χ+αχχ+βχ 3 is solved numerically by the differential transform method. This technique doesn’t require any discretization, linearization or small perturbations and therefore it reduces significantly the numerical computation. The current results of this paper are in excellent agreement with those provided by Chandrasekar et al. [1] and thereby illustrate the reliability and the performance of the differential transform method. We have also compared the results with the classical Runge-Kutta 4 (RK4) Method. 展开更多
关键词 Modified EQUATIONS of Emden Type DIFFERENTIAL Transforms METHOD RUNGE-KUTTA 4 (rk4) METHOD
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Nanofluid Heat Transfer in Irregular 3D Surfaces under Magnetohydrodynamics andMulti-Slip Effects
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作者 Mumtaz Khan Muhammad Shoaib Anwar +1 位作者 Mudassar Imran Amer Rasheed 《Frontiers in Heat and Mass Transfer》 EI 2024年第5期1399-1419,共21页
This study employs the Buongiorno model to explore nanoparticle migration in a mixed convection second-grade fluid over a slendering(variable thickness)stretching sheet.The convective boundary conditions are applied t... This study employs the Buongiorno model to explore nanoparticle migration in a mixed convection second-grade fluid over a slendering(variable thickness)stretching sheet.The convective boundary conditions are applied to the surface.In addition,the analysis has been carried out in the presence of Joule heating,slips effects,thermal radiation,heat generation and magnetohydrodynamic.This study aimed to understand the complex dynamics of these nanofluids under various external influences.The governing model has been developed using the flow assumptions such as boundary layer approximations in terms of partial differential equations.Governing partial differential equations are first reduced into ordinary differential equations and then numerically solved using the Runge-Kutta-Fehlberg method(RK4)in conjunction with a shooting scheme.Our results indicate significant increases in Nusselt and Sherwood numbers by up to 14.6%and 23.2%,respectively,primarily due to increases in the Brownian motion parameter and thermophoresis parameter.Additionally,increases in the magnetic field parameter led to a decrease in skin friction coefficients by 37.5%.These results provide critical insights into optimizing industrial processes such as chemical production,automotive cooling systems,and energy generation,where efficient heat andmass transfer are crucial.Buongiornomodel;velocity-slip effects;Joule heating;convective boundary conditions;Runge-Kutta-Fehlberg method(RK4). 展开更多
关键词 Buongiorno model velocity-slip effects Joule heating convective boundary conditions Runge-Kutta-Fehlberg method(rk4)
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