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Shape Setup System for 1700 Hot Strip Mill

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Journal of Iron and Steel Research International 2007年第5期14卷 27-30页

作者： GUO zhong-feng xu jian-zhong LI Chang-sheng LIU Xiang-hua State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

Shape setup （SSU） system is the core technology for hot strip mill （HSM）. A precise SSU system was used to improve the strip quality for HSM. The function of SSU, setup, and feedback was introduced. The main mathematical models of roll gap profile and longitudinal strain difference are set up. Strip profile allocation strategy was researched according to the SSU system of a domestic 1 700 mm HSM. The SSU system was put into practical use and the measurement results showed that strip flatness variation and strip profile variation could be controlled in target scope.

关键词： SSU hot strip mill, shape strip profile flatness

Improvement on Conventional Load Distribution Algorithm in Hot Tandem Mills

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Journal of Iron and Steel Research International 2007年第2期14卷 36-41页

作者： LIHai-jun xu jian-zhong WANG Guo-dong LIU Xiang-hua State Key Laboratory of Rolling Teehnology and Automation Northeastern University Shenyang 110004 Liaoning China

Load distribution is a key technology in strip hot rolling process, which influences the coil＇s mierostrueture and performance. Currently, Newton-Raphson algorithm is applied to load distribution of hot tandem mills in many hot rolling plants and has some serious defects such as having a strict restriction on initial iterative calculation value and requiring coefficient matrix of nonlinear equations to be nonsingular. To eliminate these defects and improve the online performance of the process control computer, Newton descendent numeric algorithm is introduced to this field to widen the initial value range and a new model named error conversion algorithm is put forth to deal with special conditions when the coefficient matrix is singular. Furthermore, considering the characteristics of load distribution, a condition of strip thickness distribution abnormality and corresponding solutions are provided which ensure that rolling parameters can be calculated normally. Simulation results show that the improved algorithm has overcome the defects of the Newton-Raphson algorithm and is suitable for online application.

关键词： load distribution hot tandem mill process control computer Newton-Raphson algorithm

Analysis of Temperature Field and Thermal Crown of Roll During Hot Rolling by Simplified FEM

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Journal of Iron and Steel Research International 2006年第6期13卷 27-30,48页

作者： GUO zhong-feng LI Chang-sheng xu jian-zhong LIU Xiang-hua WANG Guo-dong State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

Thermal crown of roll is an important factor, which affects strip profile. It is necessary to analyze the temperature field and thermal crown of roll for hot strip mill. A new simplified finite element method （FEM） was used to analyze the temperature field and thermal crown of roll, and corresponding models were built according to the practical boundary conditions. Transient roll temperature field and thermal crown were simulated by ANSYS FEM software with considering transient thermal contact and complex boundary condition. Temperature and thermal crown variations on roll surface nodes were obtained. The thermal crown results of roll obtained by FEM simulation were in good agreement with the measured data, indicating that simplified FEM models and results were correct.

关键词： temperature field thermal crown FEM roll

新型电力系统下虚拟电厂需求响应潜力评估方法研究

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价值工程 2024年第29期43卷 51-54页

作者：许建中何作为程鹏吴非国网安徽省电力有限公司庐江县供电公司庐江231500

随着新型电力系统的建设,虚拟电厂(Virtual Power Plant,VPP)在整合分布式能源、可控负荷以及储能资源方面发挥着重要作用。评估虚拟电厂中不同用户的需求响应潜力对于优化电网调度、提升电网运行效率具有重要意义。本文提出了一种基于... 详细信息

随着新型电力系统的建设,虚拟电厂(Virtual Power Plant,VPP)在整合分布式能源、可控负荷以及储能资源方面发挥着重要作用。评估虚拟电厂中不同用户的需求响应潜力对于优化电网调度、提升电网运行效率具有重要意义。本文提出了一种基于负荷时间弹性和价格弹性相结合的需求响应潜力评估方法,并结合熵权法确定各指标的权重,旨在实现对用户需求响应能力的全面量化评估。通过对浙江金华地区典型电力用户的实证分析,本文验证了所提出方法的有效性和实用性。研究结果表明,负荷时间弹性在评估中起到了关键作用,而价格弹性影响相对较小。此外,本文的方法能够通过数据驱动的聚类分析,识别不同用户的负荷特性,从而为虚拟电厂的优化调度提供依据。本文的研究为新型电力系统下虚拟电厂的需求响应管理提供了理论支持,并为未来研究指出了进一步改进的方向。

关键词：虚拟电厂需求响应负荷弹性熵权法潜力评估

基于DFT的旋转变压器信号偏差矫正方法研究

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电力电子技术 2024年第1期58卷 32-35页

作者：许中舰刘维亭魏海峰江苏科技大学自动化学院江苏镇江212000

解码芯片在对旋转变压器输出的位置信号做处理的过程中,芯片在采样时容易产生各种非理想偏差,这会造成转子位置估算精度的急剧下降。针对该问题,分析了电压信号中的幅值偏差和正交偏差会对旋转变压器解码的输出角度叠加一个2倍频的波动... 详细信息

解码芯片在对旋转变压器输出的位置信号做处理的过程中,芯片在采样时容易产生各种非理想偏差,这会造成转子位置估算精度的急剧下降。针对该问题,分析了电压信号中的幅值偏差和正交偏差会对旋转变压器解码的输出角度叠加一个2倍频的波动,直流偏差会叠加一个同频波动的问题,提出了一种基于离散傅里叶变换(DFT)的输入矫正法用于实现旋转变压器输出信号的偏差矫正,同时有效降低一次二次波动。该方法首先离散采样信号,通过DFT公式提取旋转变压器输出信号的直流信号和基频信号;然后基于直流信号和基频信号先后计算直流偏差、幅值偏差和正交偏差,通过控制器实现偏差值矫正。最后,仿真和试验结果表明,在芯片采样产生偏差时,所提出的偏差提取方法有效,试验中相应的正余弦输出信号指定阶次的波动更小。

关键词：旋转变压器解码离散傅里叶变换非理想偏差

Graphite-polypyrrole coated 316L stainless steel as bipolar plates for proton exchange membrane fuel cells

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International Journal of Minerals,Metallurgy and Materials 2011年第1期18卷 53-58页

作者： Li-jun Yang Hai-jun Yu Li-jun jiang Lei Zhu xu-yu jian zhong Wang Energy Materials and Technology Research Institute Beijing General Research Institute for Nonferrous Metals Beijing 100088 China

316L stainless steel（SS 316L） is quite attractive as bipolar plates in proton exchange membrane fuel cells（PEMFC）.In this study,graphite-polypyrrole was coated on SS 316L by the method of cyclic *** surface morphology and chemical composition of the graphite-polypyrrole composite coating were investigated by scanning electron microscopy（SEM） and X-ray photoelectron spectroscopy（XPS）.A simulated working environment of PEMFC was applied for testing the corrosion properties of graphite-polypyrrole coated SS *** current densities in the simulated PEMFC anode and cathode conditions are around 3×10-9 and 9×10-5 A·cm-2,*** addition,the interfacial contact resistance（ICR） was also *** ICR value of graphite-polypyrrole coated SS 316L is much lower than that of bare SS ***,graphite-polypyrrole coated SS 316L indicates a great potential for the application in PEMFC.

关键词： proton exchange membrane fuel cells polypyrrole graphite corrosion contact resistance stainless steel

Development of Strip Flatness and Crown Control Model for Hot Strip Mills

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Journal of Iron and Steel Research International 2010年第3期17卷 21-27,45页

作者： LI Hai-jun xu jian-zhong WANG Guo-dong SHI Li-jun XIAO Yong State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China China Offshore Oil Engineering Co Ltd Tianjin 300452 China Hot Strip Plant Ganglu Iron and Steel Group Co Tangshan 064200 Hebei China

The strip flatness and crown control model is the foundation of automatic strip shape control. Considering the metal transverse flows and the inter stand second deformation, the trip flatness and crown control model has been developed, which can be applied to CVC mills and PC mills as well as normal four-high mills. The strip flatness and crown control model has high precision, and has been successfully applied to the automatic strip shape control system reconstruction of Tangshan Ganglu 1 250 mm hot strip plant.

关键词： strip flatness crown automatic strip shape control hot strip influence function method

Seasonal variations of organic carbon and nitrogen in the upper basins of Yangtze and Yellow Rivers

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Journal of Mountain Science 2017年第8期14卷 1577-1590页

作者： LI Xiang-ying DING Yong-jian HAN Tian-ding xu jian-zhong KANG Shi-chang WU Qing-bai Mika Sillanp?? YU zhong-bo YU Cong-rong College of Hydrology and Water Resources/State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of Sciences University of Chinese Academy of Sciences State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of Sciences Laboratory of Green Chemistry School of Engineering ScienceLappeenranta University of Technology Department of Civil and Environmental Engineering Florida International University

The profound impacts exerted by climate warming on the Tibetan Plateau have been documented extensively, but the biogeochemical responses remain poorly understood. This study was aimed at seasonal variations of total organic carbon(TOC) and total organic nitrogen(TON) in stream water at two gauging sections(TTH, ZMD) in the upper basin of Yangtze River(UBYA) and at fourgauging sections(HHY, JM, JG, TNH) in the upper basin of Yellow River(UBYE) in 2013. Results showed that concentrations of TON exhibit higher values in spring and winter and lower values in summer. TOC exhibits higher concentrations in spring or early summer and lower concentrations in autumn or winter. Seasonal variations of TOC and TON fluxes are dominated by water flux. In total, the UBYE and UBYA delivers 55,435 tons C of organic carbon and 9,872 tons N of organic nitrogen to downstream ecosystems in 2013. Although the combined flux ofTOC from UBYA and UBYE is far lower than those from large rivers, their combined yields is higher than, or comparable with, those from some large rivers(e.g. Nile, Orange, Columbia), implying that organic carbon from the Tibetan Plateau may exert a potentially influence on regional and/or global carbon cycles in future warming climate.

关键词： Seasonal variation Total organic carbon(TOC) Total organic nitrogen(TON) Yangtze River Yellow River

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花椒油微胶囊工艺优化

中国调味品 2024年第3期49卷 112-117,124页

作者：武恺彤徐建中齐立军高伟马倩云骆霜霜河北农业大学食品科技学院河北保定071001 晨光生物科技集团股份有限公司河北邯郸057250 河北省植物天然色素产业技术研究院河北衡水057250

该研究以阿拉伯胶与辛烯基琥珀酸淀粉钠为复配壁材,采用喷雾干燥技术制备花椒油微胶囊,应用响应面试验法,以包埋率与花椒精油收率为响应值,以壁材占比、复配壁材比与喷雾干燥出风温度为响应因子,建立了二次回归方程模型,得到制备花椒油... 详细信息

该研究以阿拉伯胶与辛烯基琥珀酸淀粉钠为复配壁材,采用喷雾干燥技术制备花椒油微胶囊,应用响应面试验法,以包埋率与花椒精油收率为响应值,以壁材占比、复配壁材比与喷雾干燥出风温度为响应因子,建立了二次回归方程模型,得到制备花椒油微胶囊的最佳工艺参数:壁材占比为40%,复配壁材比(阿拉伯胶∶辛烯基琥珀酸淀粉钠)为1∶1,喷雾干燥出风温度为90℃,得到的花椒油微胶囊包埋率为93.54%,花椒精油收率为95.35%,并且在稳定性与感官评价方面均优于其他花椒产品。

关键词：花椒油微胶囊阿拉伯胶辛烯基琥珀酸淀粉钠

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