新型布缆船拖曳绞车控制系统

针对某新型布缆船拖曳绞车,设计了一种基于工业以太网和可编程逻辑控制器的拖曳绞车控制系统.为了提高拖曳绞车控制系统的智能化水平,开发了自动排缆系统和基于模糊自适应P+ID算法的恒张力控制器.将基于模糊自适应P+ID算法和基于传统PID算法的恒张力控制器进行了比较,仿真结果证明了本文设计的模糊自适应P+ID控制器要优于PID控制器.恶劣海况下的实际应用证明了本文设计的自动排缆系统和恒张力控制器的高效性和鲁棒性.     

单参数模糊PID在塑料挤出机温度控制系统中的应用

论述了SIMAT IC S7-300可编程控制器在塑料挤出机温度控制系统中的应用,控制回路采用单参数模糊P ID(比例、积分、微分)脉宽调功法。控制系统把单参数模糊P ID控制和PLC(可变程序逻辑控制器)的逻辑判断指令结合起来,使P ID控制更为灵活,能较好地满足生产过程的要求。详细描述了该系统的工作原理和PLC的硬件组成、软件编制。     

模糊神经网络自适应PID控制在烟叶复烤系统中的应用

烟叶复烤过程具有时滞、不确定、非线性特性,仅利用常规P ID控制不能使复烤过程的各项性能指标满足要求.本文提出了一种模糊神经网络自适应P ID控制器,该控制器即具有模糊控制简单和有效的非线性控制作用,又具有神经网络学习和自适应能力和P ID的广泛适应性.仿真结果表明,该控制器能对烟叶复烤过程进行有效控制.     

PID神经网络内模控制在湿法烟气脱硫中的应用

该文针对石灰石/石膏湿法烟气脱硫工艺中吸收塔浆液pH值变化过程的高度非线性、时滞性以及各种不确定性、常规P ID控制难以达到满意的控制效果,提出了一种基于改进P ID神经网络的内模控制方案,对浆液pH值变化过程进行辨识和控制。仿真结果表明,在改进P ID-NN的内模控制下,吸收塔浆液pH值很好地跟踪了系统的设定输入及其变化,体现了高度的自适应性。同时系统超调量小,稳态精度高,优于常规P ID控制。满足实时控制的要求。     

用于电力系统仿真的联合循环电站动态模型

从控制流程角度建立了一个适当简化的联合循环电站系统模型,目的在于为电力系统的实时仿真提供一个重要的组成模块。将该模型与电力网络结合,采用专业软件进行模拟,以研究整个电力系统的动态特性,为提高系统的安全性和稳定性提供理论依据。设计了一个P ID控制器,以提高系统的稳定性能。将该模型加入到一个虚拟的两区域电力系统中,采用专业软件N etom ac进行仿真,运行结果证明该模型可以用于实时仿真实验,并且验证了P ID控制器有助于提高系统的稳定性。     

基于PID神经网络的非线性系统辨识与控制

针对工业控制领域中非线性系统采用传统的控制方法不能达到满意的控制效果,提出一种基于P ID神经网络的控制方案,以对其进行辨识和控制。将P ID神经网络引入控制系统中,既具有常规P ID控制结构简单、参数物理意义明确等优点,同时又具有神经网络的并行结构和学习记忆功能及非线性映射能力。仿真结果表明:该控制系统响应速度快、超调量小、稳态精度高,能够快速跟踪系统输出并进行有效控制,且具有一定的自适应性和鲁棒性,满足实时控制的要求。     

模糊PID控制应用于液压同步控制系统的研究

液压同步控制系统工程机械中受到广泛地应用。液压同步控制系统具有非线性、参数时变、大惯性、迟滞系统等特性。模糊控制算法对控制对象具有很好的逼近作用。将模糊控制理论应用到PID控制中,提高PID控制器的控制能力。将模糊PID控制器应用到液压同步控制系统中,进一步提高液压同步控制系统的动态和系统稳定性。利用MatLab软件对液压同步系统进行建模和仿真实验。仿真结果表明基于模糊PID控制的液压同步控制系统具有很好的动态性能和系统稳态性。     

汽车ABS模糊控制方法的分析与仿真

运用模糊控制方法对汽车防抱制动系统进行了仿真研究．采用基于模糊规则的模糊控制方法，设计了基于模糊规则的普通模糊控制器，针对其缺陷采用基于智能权函数的模糊控制方法，设计了基于智能权函数的模糊控制器．对两种控制器进行仿真并比较仿真结果，表明基于智能权函数的模糊控制方法的控制效果优于基于模糊规则的模糊控制方法，且能有效克服后者的缺陷，提高整车的制动性能．     

基于模糊神经网络的变风量空调末端控制方法

针对变风量空调系统末端的稳定控制问题,根据被控对象的特点,提出了采用模糊神经网络(FNN)控制变风量空调系统末端的方案。在MATLAB仿真环境下对模糊神经网络的控制效果进行了模拟仿真,并与普通模糊控制器及典型PID控制器的控制效果进行了比较,结果表明模糊神经网络控制器可以稳定、有效的控制变风量系统的末端装置。     

基于模糊神经网络的变风量空调末端控制方法

针对变风量空调系统末端的稳定控制问题,根据被控对象的特点,提出了采用模糊神经网络(FNN)控制变风量空调系统末端的方案.在MATLAB仿真环境下对模糊神经网络的控制效果进行了模拟仿真,并与普通模糊控制器及典型PID控制器的控制效果进行了比较,结果表明模糊神经网络控制器可以稳定、有效的控制变风量系统的末端装置.     

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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