基于改进免疫遗传算法的PID参数优化仿真研究

将改进免疫遗传算法与传统PID控制的参数优化进一步结合,利用免疫遗传操作自身的特点,同时引入疫苗的实时更新理念,保证了疫苗的先进性,加速系统对于全局最优解的搜索速度。以锅炉温度为例,经MATLAB-Simulink仿真证明,应用改进免疫遗传算法,对温度PID参数进行优化,使系统具有了更好的控制性能,也保证了锅炉温度的实时控制效果。     

基于改进免疫遗传算法的PID参数优化仿真研究

将改进免疫遗传算法与传统PID控制的参数优化进一步结合,利用免疫遗传操作自身的特点,同时引入疫苗的实时更新理念,保证了疫苗的先进性,加速系统对于全局最优解的搜索速度.以锅炉温度为例,经MATLAB-Simulink仿真证明,应用改进免疫遗传算法,对温度PID参数进行优化,使系统具有了更好的控制性能,也保证了锅炉温度的实时控制效果.     

基于改进PID控制的折弯送料机器人运动轨迹误差仿真研究

为了提高折弯送料机器人的定位精度,采用遗传算法优化折弯送料机器人PID控制参数。创建折弯送料机器人折弯板材装置简图,采用增量式PID控制方程式。确定PID控制参数优化变量,采用遗传算法优化PID控制参数,给出遗传算法优化PID控制器参数的具体过程,设计PID在线调优流程。采用MATLAB软件对折弯送料机器人角位移运动误差进行仿真,输出误差变化曲线。并且,与优化前折弯送料机器人PID控制效果进行对比和分析。结果表明,折弯送料机器人连杆1、连杆2和连杆3最大误差分别从1.73×10~(-3)rad、1.91×10~(-3)rad和2.03×10~(-3)rad降低到0.42×10~(-3)rad、0.48×10~(-3)rad和0.55×10~(-3)rad,下降了75.7%、74.9%和72.9%。采用遗传算法优化增量式PID控制参数设计变量,能够提高折弯送料机器人的定位精度。     

采用模糊免疫PID控制的移动机器人避障误差仿真研究

当前,移动机器人运动规划路径较长,实际运动轨迹与理论运动轨迹误差较大。对此,设计了移动机器人模糊免疫PID控制系统,并对控制系统输出误差进行仿真验证。建立移动机器人平面简图,给出机器人运动方程式,采用平面栅格来描述机器人运动规划路径。引用传统PID控制器并进行改进,设计了模糊免疫PID控制系统,给出了移动机器人PID控制输出系统在线调节流程。采用MATLAB软件对机器人输出误差进行仿真,比较PID控制和模糊免疫PID控制输出误差大小。结果显示:移动机器人采用传统PID控制系统,稳定调节时间为1.0 s,产生的最大误差为0.83 mm,系统输出误差较大;移动机器人采用模糊免疫PID控制系统,稳定调节时间为0.5 s,产生的最大误差为0.59 mm,系统输出误差较小。移动机器人采用模糊免疫PID控制系统,响应速度快,追踪误差较小,从而提高系统的稳定性。     

采用改进神经网络PID控制的移动机器人轨迹追踪控制研究

为了提高双轮移动机器人运动轨迹追踪精度,采用改进粒子群算法优化BP神经网络PID控制器,并对控制效果进行仿真验证。创建双轮移动机器人模型简图,给出运动轨迹误差方程式。在传统PID控制基础上增加BP神经网络结构,引用粒子群算法并对其进行改进,采用改进粒子群算法优化BP神经网络PID控制调整参数,给出双轮移动机器人PID控制参数优化流程。采用数学软件MATLAB对双轮移动机器人轨迹追踪误差进行仿真验证,并与传统PID控制追踪误差进行对比。仿真曲线显示:在理想环境中,双轮移动机器人采用两种控制方法都能较好地实现轨迹追踪,追踪误差较小;在干扰波形环境中,传统PID控制双轮移动机器人追踪误差较大,而改进PID控制双轮移动机器人追踪误差较小。采用改进粒子群算法优化BP神经网络PID控制器,可以提高移动机器人运动轨迹追踪精度。     

基于改进PID控制的机床滑台运动位移跟踪误差研究

采取改进PID控制方法,通过仿真验证机床滑台跟踪结果.采用直角坐标系建立机床滑台二维简图模型,设计机床滑台闭环控制流程,定义机床滑台位置传递控制函数.采用BP神经网络结构对PID控制器进行改进,给出机床滑台位置输出误差评价指标函数.采用MAT-LAB软件检验不同控制系统跟踪结果.结果表明:在无干扰状态下,采用传统PID控制系统,滑台位置跟踪误差最大值为0.05m,采用改进PID控制系统,滑台位置跟踪误差最大值为0.02m.两种控制系统跟踪误差相差不大,都能实现滑台位置的精确定位.在有干扰状态下,采用传统PID控制系统,滑台位置跟踪误差较大,误差最大值为0.19m,而采用改进PID控制系统,滑台位置跟踪误差较小,误差最大值为0.02m.采用改进PID控制系统,能够实现机床滑台位置的精确定位,提高机床主轴对零件的加工精度.     

乳制品巴氏杀菌温度智能控制算法模拟及实验研究

采用热水箱模拟乳制品巴氏杀菌容器,研究热水箱水温的开环响应特性,建立了数学模型.运用MATLAB软件对该模型进行PID控制算法仿真研究,得到了PID控制参数的基本范围.在仿真研究所得参数的基础上,运用改进的有监督Hebb学习的单神经元自适应PID算法对热水箱水温进行控制,将其精确保持在目标温度,并且使其在有扰动的情况下具有良好的动态性能.该改进方法用于巴氏杀菌过程中的温度控制,可以确保乳制品的品质,并且降低了能耗.     

改进的BP神经网络PID控制器在气体浓度控制中的研究

针对动物缺氧实验中气体浓度控制这一时变非线性的过程,将BP神经网络与传统PID控制相结合虽然可以取得较好的控制效果,但是也存在着网络收敛速度慢、稳定性较差等问题.基于此,提出了一种基于改进的遗传算法优化的BP神经网络PID控制器.首先,该控制器对遗传算法的收敛速度和稳定性进行改进,利用改进后的遗传算法优化BP神经网络的权重初始值;然后,用优化后的BP神经网络实现PID控制参数的在线调整;最后,在MATLAB中对两种控制器进行仿真实验,结果显示,与传统的BP神经网络PID控制器相比,改进后的BP神经网络PID控制器具有更好的控制性能.     

基于IACO-PID的空调房间温度控制优化

空调房间温度控制器受外界环境干扰大,具有时变性和非线性,传统控制方法难以获得高精度的控制效果,为此提出一种基于改进蚁群算法优化PID的空调房间温度控制优化方法(IACO-PID).首先分析当前空调房间温度控制器存在的不足,然后采用蚁群算法对空调房间温度控制器控制参数求解,并针对蚁群算法的不足进行改进,最后采用仿真对比实验测试改进蚁群算法优化PID的优越性.实验结果表明,改进蚁群算法优化PID空调房间温度控制器的控制精度高,抗干扰能力强,具有较快的响应速度.     

基于改进SA-WOA算法优化热封刀温度控制系统PID参数的研究

套袋机热封刀温度通常采用PID算法进行控制,但是PID控制参数大多由人为经验设定,控制效果不佳.为解决这一问题,本文提出一种改进SA-WOA算法实现PID控制参数的自整定.首先我们利用阶跃响应曲线法建立系统的传递函数模型,再考虑鲸鱼算法以及模拟退火算法的优点,将两者进行结合;然后在此基础上对算法进行改进,提高算法的收敛速度以及优化效果;再将改进后的算法在MATLAB R2017b平台上进行仿真对比实验;最后,将仿真所得控制参数在套袋机上进行实验测试.仿真对比结果表明,相对于继电反馈算法、粒子群算法以及基于模拟退火的改进粒子群算法,本文算法优化所得参数控制效果更好.实测实验结果表明,本文算法所得参数控制效果良好,可以更好地满足实际的需求.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with