非线性系统自适应控制算法研究进展

非线性系统的自适应控制已成为当前控制领域的重要研究方向。通过总结近年来在非线性系统自适应控制方面所取得的成果,对非线性系统自适应控制器的一般形式和设计方法进行了分析与探讨。最后对非线性系统自适应控制的发展趋势进行了展望。     

净化空调系统的室内压差控制研究

净化空调系统的室内压差控制是现代净化空调系统中的一个重要环节,必须要采取有效、科学的控制方法,对需要净化区域的压差进行控制,才能保证室内空气的清洁度以及合理性流通,使室内空调系统得到更彻底的净化。为此,对净化空调系统进行研究,并对室内压差的控制进行了分析,总结了一些压差控制方法。     

四辊轧机弯辊液压伺服控制系统的研究

本文阐述了作为板型控制基础的弯辊液压伺服控制系统的研究成果,分析了对弯辊系统的控制要求及现状。对比分析了单阀控制和双阀控制.伺服阀带宽对弯辊系统性能的影响,指出了采取液压措施大大展宽弯辊力控制系统带宽的可行性及试验结果。     

新型双控制器方案的磁悬浮止推轴承控制系统

介绍了磁悬浮止推轴承的实验系统 ,该系统经过位置传感器检测其信号 ,当位置变化时 ,系统可以通过调节电磁力的大小 ,实现闭环控制。利用线性控制原理对其系统建立了数学模型。新型双控制方案采用两个控制器 :一个是跟随控制器 ;一个是抗干扰控制器。系统的跟随性能可以单独由跟随器调节 ;系统的抗干扰性能可以单独由抗干扰控制器调节。采用新型双控制方案与 I- PD控制分别对其系统进行了仿真 ,并对其仿真结果进行了比较。对新型双控制方案的控制参数进行了整定。最后 ,给出了仿真结果及结论。     

基于吹灰控制系统PLC人机开放性控制功能的探究与实现

本文针对吹灰系统触摸屏控制开放性不好,对吹灰程控系统PLC开放性的控制功能进行深入探究,发现采用PC机控制能够实现吹灰程控系统PLC开放性功能,对于吹灰系统运行和检修都十分便利,打破了吹灰系统厂家对触摸屏人机控制接口的技术垄断。     

风能转换系统神经网络控制方法综述

该文阐述了风能转换系统神经网络控制方法．在阐述风能转换系统基本控制策略的基础上,分析了风能转换系统常规控制方法的缺点和不足,对风能转换系统神经网络控制方法进行了总结和展望。     

悬臂梁系统的脉冲控制

为解决悬臂梁碰撞系统的混沌控制问题,利用脉冲微分系统理论和数值模拟技术,对悬臂梁系统的混沌控制进行了研究.结果表明:当悬臂梁碰撞系统出现混沌现象时,若在满足一定条件的时间点上对该系统施加脉冲信号,系统的混沌状态将会得到有效控制.利用龙格-库塔方法对施加了脉冲信号的系统进行了数值模拟,模拟结果表明:在固定时间点处系统的混沌状态得到了有效控制,验证了脉冲控制方法的可行性与有效性.该方法对研究建筑物的动力学行为具有一定的参考价值.     

基于PLC和现场总线通讯的矿石破碎控制系统设计

针对矿石破碎工序,设计了控制系统,介绍了系统的结构、功能。根据矿石破碎系统的工艺要求,以PLC为控制核心,以Profibus-DP总线为架构,采用智能MCC控制保护装置作为控制单位,实现了对破碎系统的控制。     

新型有轨电车自动防护系统的研究

当前有轨电车(ATP)系统采用PID控制,该控制是一种按照事先安排好的行车曲线进行速度控制的方法,这种方法的缺点是控制速度时的加减切换次数过多,既不利于平稳运行,又破坏乘坐的舒适性同时减低了停车精度。采用模糊预测控制对新型有轨电车的ATP系统进行研究,运用Visual C++6.0对整个系统进行了建模与仿真,并对仿真结果进行了分析。实验结果表明:在采用模糊预测控制之后,新型有轨电车ATP系统的性能得到了改善和提高,克服了PID控制的不足。     

基于UML的城轨列车运行控制仿真系统建模与实现

利用UML对北京地铁一号线列车运行控制系统进行了分析和建模,提出了一种适用于城轨列车运行控制仿真系统的分层模型,并在实验室对北京地铁一号线列车运行控制系统进行了仿真,实验结果表明:该仿真系统模型符合实际列车运行控制系统原理.     

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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