单机架可逆轧机板形测控系统的研究与设计

为提高鞍钢单机架可逆轧机板形控制系统的自动化水平和产品板形的控制精度,设计开发了采用国产压磁式冷带轧机板形仪的板形测控系统.对该板形测控系统的结构、原理及实现予以详细介绍.针对该轧制板形控制的特点,利用板形功效系数对板形自动控制系统模型进行设计.研究结果表明,利用功效系数方法可以调高板形控制系统的精度.通过板形在线检测系统的投入,使被轧带材板形质量有了较大程度的提高,板形偏差控制在±50μm/m.     

板形计法的定义及实验应用

板形测控数学模型、解析板形刚度理论和板形板厚协调规律的综合称为板形计法。采用两种实验方式验证了板形计法的正确性和实用性,其一是通过轧铝板实验,计算轧机板形刚度和轧件板形刚度,由实测铝板凸度验证板形刚度方程;其二是由CVC板形控制热连轧机实测数据,用离线计算自适应系数的方法验证板形测控数学模型。     

基于神经网络模式识别的板形模糊控制器

提出一种基于CMAC(Cerebellar Model Articulation Controller)神经网络的板形缺陷模式识别方法,并基于模式识别结果设计了板形模糊控制器.将模式识别与控制器设计合二为一,利用CMAC神经网络识别出相对于6种常见板形缺陷基本模式的隶属度,直接作为板形模糊控制器的前件部,实现了隶属度的求取功能.通过对板形缺陷特征的分析,合理定义了模糊集合,大大地减少了模糊推理的计算量.仿真结果表明,该板形模式识别方法识别精度高,设计的板形模糊控制器可以快速将板形缺陷控制到期望目标,板形控制性能良好.     

板形模式高斯分解

分析现有板形模式分解方法的缺陷，提出了一种新的板形高斯模式分解．该方法不仅大大提高了板形曲线的拟合精度，而且更加适合于板形调控机构进行板形控制，尤其是板形分段冷却控制系统及局部辊型调节控制系统．     

1450 mm冷连轧机多变量最优板形闭环控制策略研究与应用

为了提高冷轧带钢的板形控制质量,通过理论计算结合现场生产条件制定了板形闭环控制系统的控制策略。在此基础上,设计了板形闭环控制系统的系统结构,建立了以板形调控功效为基础的多变量板形闭环控制算法。给出了分步求解各个板形调节机构调节量的计算方法,既避免了通过求导方式进行全局最优化计算时产生的矩阵奇异无解的状况,又在最大程度上降低了工作辊弯辊等调节机构输出饱和的情况。在板形闭环控制系统的设计中,给出了板形调节机构的变增益补偿设定环节。开发的冷轧板形控制系统已用于1450冷连轧机的板形控制过程中,经现场应用表明,板形闭环控制系统具有较强的消差能力,为冷轧板带生产实现精确的板形控制提供了必要条件。     

智能方法在板形控制中的应用

介绍了智能方法在轧制领域特别是在板形控制中的研究进展。阐述了神经网络、模糊控制、遗传算法、粒子群算法等智能方法在板形模式识别模型、板形预报模型、板形控制的液压弯辊控制模型和轧辊分段冷却控制模型中的应用,表明将智能方法引入板形控制中,改变了依赖经验和传统方法进行板形控制的局面,为板形控制建模走出了一条新途径。     

铝带坯铸轧板形测控的补偿模型

根据铸轧板形缺陷的表征特点及其评价指标 ,采用铸轧板带的横向板厚分布作为板形控制信号 ,并依此建立了铸轧板形的数学描述 .基于铸轧工艺的特点 ,在铸轧板形实测信号中通常包含铸轧带材横向温差及板凸度所致的两种附加干扰 ,通过具体分析两种附加干扰对铸轧板形测控的影响 ,分别建立了附加温差板形补偿模型和附加板凸度板形补偿模型 .针对某铸轧机实轧工况 ,运用所建补偿模型求得了横向板厚的补偿值 ,并直接对板形检测信号进行修正 ,以期提高板形控制精度 ,避免板控执行机构的误操作 .实测结果表明所建补偿模型正确 ,且处理方法简单 ,可直接用于铸轧板形的控制 .图 1,表 1,参 10     

贝尔曼动态规划在板形板厚协调控制中的应用

针对板形控制技术在板带材生产过程中所起到的重要意义，介绍了一种用板带工艺的方法来进行板形控制的新思想。通过在新板形控制理论中运用动态规划方法从而实现了板形板厚的协调控制，对提高我国的板形控制水平具有一定的应用价值。     

张力对板形影响的实验研究

板形是板带材产品的重要质量指标之一,板形问题是目前轧钢领域研究的一个热点问题.板形质量受许多因素的影响,所以影响板形的因素一直是板形问题研究的重要内容.以往的研究大多是基于数值模拟或离线的方法,实验研究的工作开展得较少.采用实验的方法对张力对板形的影响进行了研究,研究的结论对制定与完善板带轧制规程、提高板形质量具有重要意义.     

基于量子粒子群算法的BP网络板形模式识别研究

针对目前板形模式识别方法存在的问题,以及考虑到现代轧机板形控制手段的多样化和板形控制能力的提高,为了提高板形模式识别模型的精度,本文以1次、2次、3次和4次勒让德正交多项式为板形基本模式,建立了基于量子粒子群-BP算法混合优化神经网络的新型板形模式识别模型。仿真实验表明,该模型抗干扰能力强、识别精度高、速度快,可以为板形控制策略的制定提供可靠依据。     

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