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Optimal control of a Tandem Cold Rolling System for Tracking Problem

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Journal of Materials Science & Technology 1989年第3期5卷 179-185页

作者：吴国发徐哲卓兵 Central Iron and Steel Research Institute BeijingChina

The optimal control principle and procedure of a tandem cold rolling system for tracking problem have been proposed in this paper for the first time. The state-space description of the tandem cold rolling system for the cold-strip mill of Wuhan Iron and Steel Company is: x_(k+1)=Ax_k+(_k,y_k=Cx_k+η_k The optimum performance index of the system for tracking problem is: J_(min)=minEr[(1/2)sum from k=0 to m e'_kOe_k sum from k=0 to m-1 u'_kRu_k] The authors have deduced the optimal control of the system for tracking problem as follows u_k~*=-S_k(Ay_k+_(k+1)-) the feedback gain matrix S_k is given by S_k=(B'P_(k+1)B-R)^(-1)B'P_(k+1) Pk satisfies the matrix difference equation p_k=P_(k+1)-[(S_k^(-1))'-B']^(-1)R(S_k^(-1)-B)^(-1)+Q with terminal condition P_m=Q. On the above-mentioned principle of optimal control,an optimal control procedure of the tandem cold rolling system has been obtained, and a computer simulation has been performed. The results of the simulation are satisfactory.

关键词： optimal control tracking systems cold rolling thickness control

Preparation of high performance thin-film polarizers

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Chinese Optics Letters 2010年第6期8卷 624-626页

作者：朱美萍易葵张伟丽范正修贺洪波邵建达 Key Laboratory of High Power Laser Materials Shanghai Institute of Optics and Fine MechanicsChinese Academy of Sciences Graduate University of Chinese Academy of Sciences

The optical performance of thin film polarizers is highly sensitive to the layer thicknesses of thin *** thicknesses of the sensitive layers are optimized in order to gain broader polarizing zone in such case when the total layer thickness does not *** automatic layer thickness control system is established,and errors caused by different monitoring methods are *** this thickness control system,thin-film polarizers with Tp higher than 98%and Tp/Ts higher than 200：1（Tp and Ts are transmissions for p- and s-polarizations,respectively） with the bandwidth of 11 nm are *** the system allows for optimum repeatability of three successive runs.

关键词： control systems Optical instruments thickness control Thin films

Research on film thickness of conductive line formed by laser micro-fine cladding and flexibly direct writing technique

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Chinese Optics Letters 2004年第11期2卷 654-657页

作者：李慧玲曾晓雁李惠芬李祥友陈佚群 State Key Laboratory of Laser Technology Huazhong University of Science and Technology Wuhan 430074 Department of Industrial and Systems Engineering The Hong Kong Polytechnic University Hung Hom Kowloon Hong Kong

The conventional technology could not fulfill the rapidly growing need for fine conductive lines for its inherent limits. Therefore, in this study laser micro-fine cladding and flexibly direct writing technique is used to obtain conductive lines with high precision and reliability. In the case of different substrates and parameters, film thickness will be different. Film thickness directly influences the reliability and stability of conductive lines with exception of quality and running speed. Therefore, we focus on developing the optimal parameters for the different substrates to achieve expected film thickness and make conductive lines have good performance and quality.

关键词： Cladding (coating) Conductive films Fiber lasers thickness control

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单晶二维材料生长中的层数调控机制

Science Bulletin 2023年第23期68卷 2936-2944,M0005页

作者：张磊宁孔潇董际臣丁峰 Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green Applications MOE Key Laboratory of Cluster ScienceSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China State Key Laboratory of Information Functional Materials 2020 X-LabShanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic SolidsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China Faculty of Materials Science and Engineering/Institute of Technology for Carbon Neutrality Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China

最近,通过将外延生长的多层二维晶畴进行无缝拼接,研究人员成功实现了晶圆级单晶二维多层材料的合成.不同于以往观察到的类似婚礼蛋糕或倒置婚礼蛋糕结构,这些多层二维晶畴中所有层都具有完全相同的尺寸和形状,即多层同步生长.基于此,... 详细信息

最近,通过将外延生长的多层二维晶畴进行无缝拼接,研究人员成功实现了晶圆级单晶二维多层材料的合成.不同于以往观察到的类似婚礼蛋糕或倒置婚礼蛋糕结构,这些多层二维晶畴中所有层都具有完全相同的尺寸和形状,即多层同步生长.基于此,本文通过理论计算探索了多层二维材料的不同生长模式,提出了多层同步生长的物理模型,揭示了基底上液体异质表面层的形成是保证同步生长的关键性因素.作者指出在生长过程中,多层二维材料嵌入在衬底的异质表面层中,同时底层与固态基底直接接触.异质层能有效钝化二维材料的边缘,从而防止这些活性边缘的融合,而异质层与基底之间的高界面则迫使不同层的二维材料边缘保持同步生长.通过对多层同步生长机理的深入了解,本文揭示了发生多层同步生长的条件,为合成层数可控的晶圆级单晶二维材料提供了新的思路.

关键词： 2D materials Epitaxial growth thickness control Synchronic growth

Application of Reduction Modifying in Hot Strip Continuous-Rolling Process controlling

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Application of Reduction Modifying in Hot Strip Continuous-R...

The Techniques to Reduce Variations within One Plate

第二十六届中国控制会议

作者： Wang Xiaolin,Yue Zongmin Department of Computer Science & Technology,Anhui University of Technology,Ma''anshan 243002,Anhui Province,P.R.China

Strip thickness is an important factor of strip *** experienced physical model is not suit for solving the problem of strip thickness fluctuation which resulted from data abnormality in product process.A new method of modifying reduction is presented to solve the *** method controls strip thickness by combining scene real-time metrical data with experienced physical model,modifying reduction and keeping balance of *** the method,the eligible ratio of finished product is advanced and the influence of data abnormality is *** new method is of great significance to guarantee the fault tolerance of control system and stability of production and product quality.

关键词： Process control Reduction Hot strip continuous rolling thickness control

来源： cnki会议评论

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Journal of Beijing Institute of Technology 1996年第2期5卷 154+148-154页

作者：梁启宏张迪生耿庆波陈锦娣北京理工大学自动控制系

Conventional techniques to control variations within one plate have been based on preset models and constant automatic position control (APC or pressure feedback automatic gauge control(PAGC).*** of the rolling force prediction error in the preset models and of the inadequate response speed of dynamic system and of the eccentricity, etc.,the conventional method has not given satisfactory results, the statistics'variations within one plate are in range of 0.25-0.60 mm The authors have developed the techniques to control the variations, which are dynamic intelligent control of hydraulic screwdown system. synchronism control of hydraulic screwdown, eccentricity control method by rotary encoder and the curve of modulus of mill measured automatically, etc., The techniques were fully and successfully industrialized in The Plate Mill of Maanshan Iron and Steel Company and good results that variations are in range of 0.08-0.15min hare been obtained in that mill.

关键词： automatic gauge control (AGC) rolling mills thickness control computer control