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Simulation of Steel Reinforcement on the Nonlinear Behaviour of Slender Glulam Beam Columns by Using the Newton-Raphson Method
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作者 Martial Ourmama Marcelline Blanche Manjia Edmond Dawak Fezeu 《Open Journal of Applied Sciences》 2024年第2期243-266,共24页
The current theory in NF EN 1995-1-1/NA of Eurocode 5, which is based on maximum deflection, has been investigated on softwoods. Therefore, this theory is not adapted for slender glulam beam columns made of tropical h... The current theory in NF EN 1995-1-1/NA of Eurocode 5, which is based on maximum deflection, has been investigated on softwoods. Therefore, this theory is not adapted for slender glulam beam columns made of tropical hardwood species from the Congo Basin. This maximum deflection is caused by a set of loads applied to the structure. However, Eurocode 5 doesn’t provide how to predict this deflection in case of long-term load for such structures. This can be done by studying load-displacement (P-Δ) behaviour of these structures while taking into account second order effects. To reach this goal, a nonlinear analysis has been performed on a three-dimensional beam column embedded on both ends. Since conducting experimental investigations on large span structural products is time-consuming and expensive especially in developing countries, a numerical model has been implemented using the Newton-Raphson method to predict load-displacement (P-Δ) curve on a slender glulam beam column made of tropical hardwood species. On one hand, the beam has been analyzed without wood connection. On the other hand, the beam has been analyzed with a bolted wood connection and a slotted-in steel plate. The load cases considered include self-weight and a uniformly applied long-term load. Combinations of serviceability limit states (SLS) and ultimate limit states (ULS) have also been considered, among other factors. A finite-element software RFEM 5 has been used to implement the model. The results showed that the use of steel can reduce displacement by 20.96%. Additionally, compared to the maximum deflection provided by Eurocode 5 for softwoods, hardwoods can exhibit an increasing rate of 85.63%. By harnessing the plastic resistance of steel, the bending resistance of wood can be increased by 32.94%. 展开更多
关键词 Nonlinear Analysis newton-raphson method Maximum Deflection Bolted Wood Connection Hardwood Species
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Multi-train modeling and simulation integrated with traction power supply solver using simplified Newton–Raphson method 被引量:5
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作者 Thanatchai Kulworawanichpong 《Journal of Modern Transportation》 2015年第4期241-251,共11页
Multi-train modeling and simulation plays a vital role in railway electrification during operation and planning phase. Study of peak power demand and energy consumed by each traction substation needs to be deter- mine... Multi-train modeling and simulation plays a vital role in railway electrification during operation and planning phase. Study of peak power demand and energy consumed by each traction substation needs to be deter- mined to verify that electrical energy flowing in its railway power feeding system is appropriate or not. Gauss-Seidel, conventional Newton-Raphson, and current injection methods are well-known and widely accepted as a tool for electrical power network solver in DC railway power supply study. In this paper, a simplified Newton-Raphson method has been proposed. The proposed method employs a set of current-balance equations at each electrical node instead of the conventional power-balance equation used in the conventional Newton-Raphson method. This concept can remarkably reduce execution time and computing complexity for multi-train simulation. To evaluate its use, Sukhumvit line of Bangkok transit system (BTS) of Thai- land with 21.6-km line length and 22 passenger stopping stations is set as a test system. The multi-train simulation integrated with the proposed power network solver is developed to simulate 1-h operation service of selected 5-min headway. From the obtained results, the proposed method is more efficient with approximately 18 % faster than the conventional Newton-Raphson method and just over 6 % faster than the current injection method. 展开更多
关键词 newton-raphson method Gauss-Seidelmethod - Current-balance equation Current injectionmethod Multi-train simulation Power supply study
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基于Newton-Raphson法的非线性方程组求解研究
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作者 郭华毅 《大理大学学报》 2023年第12期1-4,共4页
牛顿-拉弗森(Newton-Raphson)法也叫作牛顿迭代法,是一种近似求解方程的方法,适用于复数域和实数域。作为数值分析中最重要的方法之一,它不仅适用于微分方程和积分方程的求解,而且适用于非线性方程组的求解。解析Newton-Raphson法的基... 牛顿-拉弗森(Newton-Raphson)法也叫作牛顿迭代法,是一种近似求解方程的方法,适用于复数域和实数域。作为数值分析中最重要的方法之一,它不仅适用于微分方程和积分方程的求解,而且适用于非线性方程组的求解。解析Newton-Raphson法的基本原理,并结合案例分析证明Newton-Raphson法在非线性方程组求解中的实际应用。 展开更多
关键词 牛顿-拉弗森法 泰勒展开式 数值分析 非线性方程组
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Forward kinematics analysis of parallel manipulator using modified global Newton-Raphson method 被引量:20
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作者 杨炽夫 郑淑涛 +2 位作者 靳军 朱思斌 韩俊伟 《Journal of Central South University》 SCIE EI CAS 2010年第6期1264-1270,共7页
In order to obtain direct solutions of parallel manipulator without divergence in real time,a modified global Newton-Raphson(MGNR) algorithm was proposed for forward kinematics analysis of six-degree-of-freedom(DOF) p... In order to obtain direct solutions of parallel manipulator without divergence in real time,a modified global Newton-Raphson(MGNR) algorithm was proposed for forward kinematics analysis of six-degree-of-freedom(DOF) parallel manipulator.Based on geometrical frame of parallel manipulator,the highly nonlinear equations of kinematics were derived using analytical approach.The MGNR algorithm was developed for the nonlinear equations based on Tailor expansion and Newton-Raphson iteration.The procedure of MGNR algorithm was programmed in Matlab/Simulink and compiled to a real-time computer with Microsoft visual studio.NET for implementation.The performance of the MGNR algorithms for 6-DOF parallel manipulator was analyzed and confirmed.Applying the MGNR algorithm,the real generalized pose of moving platform is solved by using the set of given positions of actuators.The theoretical analysis and numerical results indicate that the presented method can achieve the numerical convergent solution in less than 1 ms with high accuracy(1×10-9 m in linear motion and 1×10-9 rad in angular motion),even the initial guess value is far from the root. 展开更多
关键词 parallel manipulator forward kinematics global newton-raphson real-time system
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A Distributed Newton Method for Processing Signals Defined on the Large-Scale Networks
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作者 Yanhai Zhang Junzheng Jiang +1 位作者 Haitao Wang Mou Ma 《China Communications》 SCIE CSCD 2023年第5期315-329,共15页
In the graph signal processing(GSP)framework,distributed algorithms are highly desirable in processing signals defined on large-scale networks.However,in most existing distributed algorithms,all nodes homogeneously pe... In the graph signal processing(GSP)framework,distributed algorithms are highly desirable in processing signals defined on large-scale networks.However,in most existing distributed algorithms,all nodes homogeneously perform the local computation,which calls for heavy computational and communication costs.Moreover,in many real-world networks,such as those with straggling nodes,the homogeneous manner may result in serious delay or even failure.To this end,we propose active network decomposition algorithms to select non-straggling nodes(normal nodes)that perform the main computation and communication across the network.To accommodate the decomposition in different kinds of networks,two different approaches are developed,one is centralized decomposition that leverages the adjacency of the network and the other is distributed decomposition that employs the indicator message transmission between neighboring nodes,which constitutes the main contribution of this paper.By incorporating the active decomposition scheme,a distributed Newton method is employed to solve the least squares problem in GSP,where the Hessian inverse is approximately evaluated by patching a series of inverses of local Hessian matrices each of which is governed by one normal node.The proposed algorithm inherits the fast convergence of the second-order algorithms while maintains low computational and communication cost.Numerical examples demonstrate the effectiveness of the proposed algorithm. 展开更多
关键词 graph signal processing distributed newton method active network decomposition secondorder algorithm
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A Transient Thermohydrodynamics Study of Plain Journal Bearings Using Newton-Raphson Method Analysis
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作者 富彦丽 马希直 朱均 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2003年第4期233-240,共8页
The present paper proposes three-dimensional model necessary to calculate the transient temperature field in a journal bearing submitted to a sudden change in speed and load and analyzes the bearing performance numeri... The present paper proposes three-dimensional model necessary to calculate the transient temperature field in a journal bearing submitted to a sudden change in speed and load and analyzes the bearing performance numerically. Thermal deformation of the bush and realistic thermal boundary conditions at oil and bush interface are considered. At each time step a Newton-Raphson method is used to solve the Reynolds equation, film thickness equation and the motion equation of the journal simultaneously to obtain the pressure distribution and the velocity of the journal center. Then the fluid film force is acquired through integral of fluid film force and the acceleration and position of the journal center are acquired through differences of the velocity. The energy equations of the oil film and the bush are solved simultaneously by using an efficient finite difference scheme. Then the transient three dimensional temperature field of the bearing is acquired by combining the energy equations and the Reynolds equation through the nodal temperature and pressure. It is found that the approaches introduced here converge quickly and save calculation time greatly. 展开更多
关键词 thermohydrodynamics TRANSIENT newton-raphson method journal bearing
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MULTI-PARAMETER ACCELERATED MODIFIED NEWTON-RAPHSON METHODS FOR RIGIDPLASTIC FE ANALYSIS
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作者 Shi Gang Liu Xiaolin 《Acta Mechanica Solida Sinica》 SCIE EI 2002年第4期323-331,共9页
Applications of certain multi-parameter acceleration techniques used with themodified New-ton-Raphson (mN-R) methods to solve the nonlinear equations arising from rigid-plasticfinite element analysis are investigated.... Applications of certain multi-parameter acceleration techniques used with themodified New-ton-Raphson (mN-R) methods to solve the nonlinear equations arising from rigid-plasticfinite element analysis are investigated. New modified multi-parameter techniques, developed fromCrisfield's multi-parameter methods, are utilized to solve these nonlinear equations. The numericalperformance of these techniques is compared with the standard Newton-Raphson method (sN-R),Crisfield's single parameter method (C1), Crisfield's two parameter method (C2) and Crisfield'sthree parameter method (C3). The new techniques do not involve additional residual force calculationand require little extra computational effort. In addition, they are more robust and efficient thanother existing acceleration techniques. 展开更多
关键词 rigid-plastic FEM standard newton-raphson method modified newton-raphsonmethod crisfield's multi-parameter accelerated techniques modified multi-parameter acceleratedtechniques
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Principle of MSD floating-point division based on Newton-Raphson method on ternary optical computer
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作者 沈云付 胡鹏飞 樊孝领 《Journal of Shanghai University(English Edition)》 CAS 2011年第5期347-351,共5页
The division operation is not frequent relatively in traditional applications, but it is increasingly indispensable and important in many modern applications. In this paper, the implementation of modified signed-digit... The division operation is not frequent relatively in traditional applications, but it is increasingly indispensable and important in many modern applications. In this paper, the implementation of modified signed-digit (MSD) floating-point division using Newton-Raphson method on the system of ternary optical computer (TOC) is studied. Since the addition of MSD floating-point is carry-free and the digit width of the system of TOC is large, it is easy to deal with the enough wide data and transform the division operation into multiplication and addition operations. And using data scan and truncation the problem of digits expansion is effectively solved in the range of error limit. The division gets the good results and the efficiency is high. The instance of MSD floating-point division shows that the method is feasible. 展开更多
关键词 ternary optical computer (TOC) modified signed-digit (MSD) division newton-raphson method SCAN data truncation
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Numerical Methods for a Class of Quadratic Matrix Equations
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作者 GUAN Jinrui WANG Zhixin SHAO Rongxia 《应用数学》 北大核心 2024年第4期962-970,共9页
Quadratic matrix equations arise in many elds of scienti c computing and engineering applications.In this paper,we consider a class of quadratic matrix equations.Under a certain condition,we rst prove the existence of... Quadratic matrix equations arise in many elds of scienti c computing and engineering applications.In this paper,we consider a class of quadratic matrix equations.Under a certain condition,we rst prove the existence of minimal nonnegative solution for this quadratic matrix equation,and then propose some numerical methods for solving it.Convergence analysis and numerical examples are given to verify the theories and the numerical methods of this paper. 展开更多
关键词 Quadratic matrix equation M-MATRIX Minimal nonnegative solution newton method Bernoulli method
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基于Newton-Raphson迭代的永磁同步电机MTPA控制算法设计
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作者 岳学磊 刘奎 +2 位作者 许克磊 田地 高闯 《技术与市场》 2023年第5期11-15,共5页
针对牵引永磁同步电机的最大转矩电流比(MTPA)的控制原理,提出一种基于Newton-Raphson迭代公式的MTPA控制算法,根据转矩指令实时计算最优的d、q轴电流参考值,充分利用了电机的磁阻转矩,以最小的电流输出最大的转矩。Newton-Raphson的迭... 针对牵引永磁同步电机的最大转矩电流比(MTPA)的控制原理,提出一种基于Newton-Raphson迭代公式的MTPA控制算法,根据转矩指令实时计算最优的d、q轴电流参考值,充分利用了电机的磁阻转矩,以最小的电流输出最大的转矩。Newton-Raphson的迭代次数为10次,最终将迭代误差降到0.01 A以下,对处理器的负担较小。通过MATLAB/Simulink仿真及在中车大连电力牵引研发中心有限公司试验中心进行试验,证明了该MTPA算法的可靠性与有效性,并在系列化标准地铁永磁牵引系统中得以应用。 展开更多
关键词 系列化标准地铁 MTPA算法 newton-raphson迭代公式 永磁同步电机
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用改进的Newton-Raphson方法生成对称的分形艺术图形 被引量:10
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作者 苏晓红 李东 胡铭曾 《计算机学报》 EI CSCD 北大核心 1999年第11期1147-1152,共6页
直接采用复平面Newton-Raphson 方法生成分形艺术图形存在显示速度慢、生成图形种类少,以及色彩搭配不合理等不足,因此该文通过对牛顿迭代函数进行分式线性映射,并在其中嵌入控制参数生成了大量的具有对称美的分形艺... 直接采用复平面Newton-Raphson 方法生成分形艺术图形存在显示速度慢、生成图形种类少,以及色彩搭配不合理等不足,因此该文通过对牛顿迭代函数进行分式线性映射,并在其中嵌入控制参数生成了大量的具有对称美的分形艺术图形,同时还设计了图形的快速显示算法,并通过合理设置256色调色板,使生成的图形色彩丰富、和谐、饱满,达到既变化又统一的美的效果. 展开更多
关键词 分形艺术图形 调色板 牛顿迭代法 图形生成
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Newton-Raphson方法优化势函数参数 被引量:6
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作者 凤尔银 张陟 郑贤锋 《安徽师范大学学报(自然科学版)》 CAS 2001年第3期222-224,共3页
确定原子分子势函数中的参数 ,这是原子分子理论计算的重要问题 .本文介绍应用Newton -Raphson方法优化势函数参数 ,给出了算法公式、主要步骤 .以Morse势为例检验表明 ,该算法简便 ,结果精度高 .
关键词 势函数 参数优化 newton-raphson方法 原子分子 量子力学计算 MORSE势
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基于Newton-Raphson迭代与PSO数字图像相关方法 被引量:15
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作者 杜亚志 王学滨 《计算机工程与应用》 CSCD 2012年第34期184-189,共6页
鉴于基于Newton-Raphson(N-R)迭代的数字图像相关方法对迭代初值的敏感性问题,提出了一种基于N-R迭代与粒子群优化(PSO)算法的数字图像相关方法。该方法利用了PSO算法中的全局搜索能力与N-R迭代中的局部搜索能力,通过它们的交替迭代以... 鉴于基于Newton-Raphson(N-R)迭代的数字图像相关方法对迭代初值的敏感性问题,提出了一种基于N-R迭代与粒子群优化(PSO)算法的数字图像相关方法。该方法利用了PSO算法中的全局搜索能力与N-R迭代中的局部搜索能力,通过它们的交替迭代以改善初值;以改善后的初值进行最后的N-R迭代。经检验,该方法比N-R迭代对初值的要求宽松。这是由于在N-R迭代与PSO算法多次交替迭代之后,位移和应变的初值都得到了一定的改善。对相似材料模型受载破坏后表面上的点的位移和应变进行了计算,获得了较好的结果。 展开更多
关键词 数字图像相关方法 newton-raphson迭代 粒子群优化算法 初值
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采用仿射变换的桨叶变形摄像测量Newton-Raphson算法 被引量:5
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作者 高亚东 刘荣明 王华明 《振动.测试与诊断》 EI CSCD 北大核心 2013年第3期432-436,526,共5页
提出一种基于仿射变换的(Newton-Raphson,简称N-R)数字图像相关算法。首先,采用人机交互的方法在变形前后的图像中选取匹配特征点,计算仿射变换参数;然后,根据仿射变换位移模式计算目标子区中心点的位移,将其用作N-R算法的初值。为降低... 提出一种基于仿射变换的(Newton-Raphson,简称N-R)数字图像相关算法。首先,采用人机交互的方法在变形前后的图像中选取匹配特征点,计算仿射变换参数;然后,根据仿射变换位移模式计算目标子区中心点的位移,将其用作N-R算法的初值。为降低计算量,采用全场插值,插值运算次数降为常规插值的1%左右。仿真测试表明,基于仿射变换的N-R算法在精度保持不变的情况下显著减少计算时间,克服了常规N-R算法计算量大、效率低、只适用于无刚体转动目标等缺陷,为开发直升机桨叶变形摄像测量系统提供了算法基础。 展开更多
关键词 直升机 摄像测量 特征点匹配 仿射变换 newton—raphson算法
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基于Newton-Raphson迭代的动压气体止推箔片轴承特性研究 被引量:5
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作者 闫佳佳 刘占生 +1 位作者 王铮 高佳颖 《汽轮机技术》 北大核心 2017年第2期116-120,124,共6页
以波箔型气体止推箔片轴承为研究对象,给出一种快速收敛的静特性数值求解方法,结合Newton-Raphson迭代法和有限差分法,耦合求解Reynolds方程和润滑膜厚度方程,研究气体止推箔片轴承的静态性能,分析结构参数对气体止推箔片轴承轴向承载... 以波箔型气体止推箔片轴承为研究对象,给出一种快速收敛的静特性数值求解方法,结合Newton-Raphson迭代法和有限差分法,耦合求解Reynolds方程和润滑膜厚度方程,研究气体止推箔片轴承的静态性能,分析结构参数对气体止推箔片轴承轴向承载力、黏性摩擦力矩的影响规律。建立转子止推盘倾斜的润滑膜厚度方程,求解获得轴承压力分布规律,分析转子止推盘倾斜对气体止推箔片轴承静态性能的影响。结果表明:采用基于NewtonRaphson迭代的数值求解方法收敛速度较快;气体止推箔片轴承的轴向承载力和黏性摩擦力矩均随箔片变形刚度的增大而增大;止推盘倾斜时气体止推箔片轴承的静态性能增大,且倾斜角度越大静态特性结果也越大。 展开更多
关键词 气体止推箔片轴承 newton—raphson迭代 轴向承载力 黏性摩擦力矩 润滑膜厚度 止推盘倾斜
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用改进的Newton-Raphson方法计算隐含波动率 被引量:2
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作者 马青华 李艳涛 吕书强 《西南师范大学学报(自然科学版)》 CAS 北大核心 2015年第7期50-53,共4页
如何利用标的资产价格的价格确定波动率函数有着重要的意义.对于欧式期权,在Black-Scholes模型框架下,分析了经典Newton-Raphson迭代格式及修正格式和二分法,有效地解决了隐含波动率的数值计算问题.最后,通过数值算例对比分析了方法的... 如何利用标的资产价格的价格确定波动率函数有着重要的意义.对于欧式期权,在Black-Scholes模型框架下,分析了经典Newton-Raphson迭代格式及修正格式和二分法,有效地解决了隐含波动率的数值计算问题.最后,通过数值算例对比分析了方法的有效性. 展开更多
关键词 欧式期权 隐含波动率 newton-raphson迭代 二分法
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板式反应精馏塔的模拟计算——修正的Newton-Raphson法 被引量:20
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作者 张瑞生 《华东化工学院学报》 CSCD 1989年第1期25-32,共8页
通过选择合适的迭代变量和分层迭代的方法,提出了一种计算机内存少、机时省且稳定收敛的板式反应精馏塔的数学模拟算法。该算法将模型方程分成内外两层迭代求解。内层以塔板上各组分的液相浓度为迭代变量,以物料衡算方程为残差函数,用Ne... 通过选择合适的迭代变量和分层迭代的方法,提出了一种计算机内存少、机时省且稳定收敛的板式反应精馏塔的数学模拟算法。该算法将模型方程分成内外两层迭代求解。内层以塔板上各组分的液相浓度为迭代变量,以物料衡算方程为残差函数,用Newton-Raphson法求解;外层以各板上汽相流量为迭代变量,用直接迭代法求解焓平衡方程。该算法能适用于非理想性较强,反应级数高于一级的系统。并附计算实例。 展开更多
关键词 精馏 板式塔 精馏塔 数学模拟
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Newton-Raphson法在无单元伽辽金法解弹塑性问题中的应用 被引量:1
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作者 向红 陈莘莘 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2002年第S2期49-52,共4页
无单元伽辽金法(EFGM)只需节点信息,不需将节点连成单元;此外,还有精度高、后处理方便等优点。本文探讨Newton-Raphson增量迭代法对无单元伽辽金法求解弹塑性平面问题的精度的影响。
关键词 newton-raphson 无单元伽辽金法 弹塑性问题
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基于Newton-Raphson法的多效顺流蒸发系统的模拟 被引量:2
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作者 徐建良 《现代化工》 CAS CSCD 北大核心 2011年第4期87-91,共5页
建立了普通、复杂顺流蒸发系统的数学模型,采用Newton-Raphson法求解,应用面向对象的Pascal语言编制了该算法的计算程序,可对二至七效常规和复杂并流蒸发系统进行模拟计算。以蔗糖溶液为例,对三效并流的5种流程进行了计算和比较,结果表... 建立了普通、复杂顺流蒸发系统的数学模型,采用Newton-Raphson法求解,应用面向对象的Pascal语言编制了该算法的计算程序,可对二至七效常规和复杂并流蒸发系统进行模拟计算。以蔗糖溶液为例,对三效并流的5种流程进行了计算和比较,结果表明将各效冷凝液全部用于预热原料的多效蒸发流程能耗最低,蒸发器面积最小。 展开更多
关键词 多效蒸发 数学模型 newton-raphson 顺流流程 模拟计算
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基于Newton-Raphson搜索算法的永磁同步电机变电感参数最大转矩电流比控制方法 被引量:15
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作者 康劲松 王硕 《电工技术学报》 EI CSCD 北大核心 2019年第8期1616-1625,共10页
内置式永磁同步电机的最大转矩电流比控制充分利用了电机的磁阻转矩,以最小铜损为目标,可以在最小电流条件下输出最大转矩。然而,永磁同步电机的电感存在磁饱和及交叉饱和特性,实际中电感参数会随电流的变化而变化,这需要结合不同电感... 内置式永磁同步电机的最大转矩电流比控制充分利用了电机的磁阻转矩,以最小铜损为目标,可以在最小电流条件下输出最大转矩。然而,永磁同步电机的电感存在磁饱和及交叉饱和特性,实际中电感参数会随电流的变化而变化,这需要结合不同电感值进行大量繁琐的标定和拟合工作。本文提出一种变电感参数的最大转矩电流比自动搜索方法,通过构建电感关于电流的三维数据表格,利用二阶Newton-Raphson(N-R)自动搜索算法,将复杂的最大转矩电流比非线性公式转化为微控制器易实现的迭代运算,提高电流分配精度,简化标定工作,仿真和实验验证了所提出算法的有效性。 展开更多
关键词 内置式永磁同步电机 最大转矩电流比控制 牛顿拉夫森搜索算法 磁饱和效应 交叉饱和效应
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