内模PID控制器在云台伺服系统中的应用

针对SG-5452460005-15W型永磁式直流减速电动机驱动的YP3091型摄像机云台伺服系统,建立了数学模型,并基于内模控制原理设计了一种新型PID控制器。该控制器设计方便,只有一个可调参数。仿真结果表明:系统的水平跟踪和仰俯跟踪误差均方根分别为0.15 mrad和0.32 mrad。与传统PID控制器相比,在内模PID控制器参数调节方面,系统跟踪响应快,精度高,抗干扰能力强,鲁棒性好。     

共轨燃油压力模糊PID控制器的设计

为了达到共轨燃油压力的动态调节，突破传统PID控制的局限性，提出一种精确控制共轨燃油压力的模糊PID控制器的设计方法．分析系统输出响应曲线，得到参数的自整定要求．由单片机计算结果确定了输入输出语言变量的论域．给出模糊控制器的调节规则和参数的模糊控制表．提出了该控制器的单片机实现方法。经试验验证，该控制器效果良好．     

具有复杂引水管道的水轮机调节系统小波动稳定性分析

根据南桠河姚河坝水电站的设计方案，对水轮机调节系统以复杂管道、弹性水锤、调速器为PID调节规律，建立其小波动数学模型，据此编制了源程序并进行了仿真计算。通过对该电站水轮机调节系统各种不同工况及参数组合的计算，得出了调速器最优参数组及其调整范围，可保证系统小波动调节稳定。     

模糊PID控制在汽车ABS中的应用与仿真研究

ABS是一种变工况、非线性的系统，参数自整定模糊PID控制可以利用模糊控制规则对PID参数进行在线修改，因而具有较好的自适应能力．设计了一种参数自整定模糊PID控制器，在分析单轮汽车模型的基础上，探讨了其在汽车ABS上的应用．采用模糊控制、PID控制、模糊PID控制三种方法分别对汽车ABS进行仿真研究，结果表明：模糊PID控制方法兼备了前面两种方法的优点，可以达到更好的控制效果．     

模糊PID控制器的设计

常规PID控制器由于简单、稳定性好、可靠性高而广泛应用于过程控制。PID调节过程的品质取决于PID控制器各个参数的整定。常规PID控制器不能在线整定参数，因而不能很好地控制非线性、时变的复杂系统和模型不清楚的系统。模糊控制器对复杂的和模型不清楚的系统能够进行简单有效地控制。因此，结合传统PID控制器的优点，同时，考虑到模糊控制实现的特点，提出了模糊PID控制器的思想。     

最优Fuzzy-GA PID控制器及其应用

提出了一种基于模糊推理与遗传算法的最优PID控制器的设计方法 .该控制器由离线和在线 2部分组成 .在离线部分 ,以系统响应的超调量、上升时间及调整时间为性能指标 ,利用遗传算法搜索出一组最优的PID参数K p ,T i 及T d ,作为在线部分调节的初始值 ;在在线部分 ,采用一个专用的PID参数优化程序 ,以离线部分获得的K p ,T i 及T d 为基础 ,根据系统当前的误差e和误差变化率 e ,通过模糊推理在线调整系统瞬态响应的PID参数 ,以确保系统的响应具有最优的动态和稳态性能 .计算机仿真结果表明 ,与传统的PID控制器相比 ,这种最优PID控制器具有良好的控制性能和鲁棒性能 ,可用于控制不同的对象和过程     

水轮机调节系统模糊PID控制器设计及仿真研究

本文基于金哨电厂水轮机调节系统数据设计了一种的水轮机调节系统模糊PID控制器,通过Matlab仿真对控制规则及量化因子、比例因子等参数进行了有效优化,并对两种控制规律进行了详细的对比分析,最终实验结果表明模糊PID控制较传统PID调节时间有约30秒左右的改善,此外,系统的鲁棒性、扰动阶跃响应特性等均有较大提高,实践表明,本文研究具有较高的理论价值。     

基于参数自调整模糊PID算法的前馈共轨压力控制

阐述了电控共轨燃油喷射系统结构及压力调节基本原理,针对压力控制传统PID算法的不足,引入参数自调整模糊PID算法,通过Matlab仿真确定了不同误差输入时的参数调整规律.为提高压力控制动态响应,设计了前馈参数自调整模糊PID算法,并通过试验确定了前馈量与相关影响因素的定量关系,最后进行了系统对比试验.结果表明,该算法在工况过渡时的性能优于常规PID控制,压力控制超调量及稳态误差精度得到明显改善,从而为电控共轨系统精确喷油计量和控制奠定了基础.     

灰色预测模糊自调节PID控制器及其仿真

结合灰色预测、模糊自调节与传统PID控制的设计思想,提出灰色预测模糊自调节PID控制算法.该算法用系统输出误差和系统输出预测误差合成的综合误差作为PID控制器的输入,同时模糊自调节系统又能根据综合误差及其变化率来调整PID参数.仿真结果表明,与模糊自调节PID控制器相比,该控制器具有良好的动态性能和鲁棒性.     

基于uCOS-II的模糊自适应温度控制系统设计

针对车间温度控制系统具有非线性、滞后性和时变性等特点,提出了一种改进型的模糊自适应PID控制器。该控制器通过在线调整学习速率因子和PID参数增量,并结合积分分离思路,实现PID参数的自适应调节。仿真结果表明该控制器优于传统PID控制和传统模糊自适应PID控制。控制系统采用PIC24F作为主控芯片,结合操作系统uCOS-II的实时性、可靠性以及模糊自适应控制的非线性、时变性等特点,通过实验成功的实现对温度准确控制。     

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     

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     

Journal of Donghua University ( English Edition) Contents of Volume 31

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