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Dynamics and control designs for internal thermally coupled distillation columns with different purities,Part 1:Open loop dynamic behaviors

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Progress in Natural Science:Materials International 2006年第5期16卷 346-351页

作者： ZHU Yu, liu xinggao and CHU Jian National Laboratory of Industrial Control Technology, Department of Control Science and Engineering, Zhejiang University, Hangzhou 310027, China [a]National Laboratory of Industrial Control Technology Department of Control Science and Engineering Zhejiang University Hangzhou China

The open loop dynamic behaviors of internal thermally coupled distillation column with four different purities (low-, moderate-, high- and very high-purity) are studied. These dynamic behaviors are characterized by strong asymmetric non-linearity, high sensitivity to operation conditions change and distinct inverse response. With the increase of purity, these dynamic behaviors are intensified and become more complex, which easily lead to the mismatch between linear model and plant and also change the relationship between manipulated and controlled variables.

关键词： thermal coupling inverse response non-linearity high purity asymmetric behavior.

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Modeling and Simulation of Heterogeneous Catalyzed Propylene Polymerization

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Chinese Journal of Chemical Engineering 2007年第4期15卷 545-553页

作者：刘兴高 State Key Laboratory of Industrial Control Technology Institute of Industrial Control Department of Control Science and Technology Zhejiang University Hangzhou 310027 China

A novel mathematical model for single particle slurry propylene polymerization rising heterogeneous Ziegler-Natta catalysts has been developed to describe the kinetic behavior, the molecular weight-distribution, the monomer concentration, the degree of polymerization, the polydispersity index （PDI）, etc. This model provides a more valid mathematical description by accounting for the monomer diffusion phenomena at two levels as multigrai model counts, and obtains results that are more applicable to the conditions existing in most polymerizations of industrial interest. Considering that some models on the mesoscale phenomena are so complex that some existingmodeling aspects have to be simplified or even neglected to make the model convenient for use in interesting engineering studies, it is very important to put some effort into determining what sort of numerical analysis works bestfor these problems. For this reason, special *** to these studies to explorean efficient algorithm usingadaptive grid-point spacing in a tlnlte-ditterence technique to tlgure out more practical mass transport models andconvection-diffusion models efficiently. The reasonable outcomes, as well as the significant computation time saving, have been achieved, thereby displaying the advantage of this calculation method.

关键词： modeling and simulation propylene polymerization mass transfer diffusion and convection

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基于内模控制的内部热耦合精馏策略

化工学报 2010年第8期61卷 2067-2071页

作者：丛琳刘兴高浙江大学控制系工业控制技术国家重点实验室浙江杭州310027

精馏过程约占工业总能耗的1/3,其节能控制潜力很大。内部热耦合精馏(ITCDIC)是迄今为止所提出的节能效果最好(比常规精馏节能40%以上)却没有商业化的节能技术。主要原因在于该过程具有较强的非线性、复杂的动态特性以及耦合性,给控制方... 详细信息

精馏过程约占工业总能耗的1/3,其节能控制潜力很大。内部热耦合精馏(ITCDIC)是迄今为止所提出的节能效果最好(比常规精馏节能40%以上)却没有商业化的节能技术。主要原因在于该过程具有较强的非线性、复杂的动态特性以及耦合性,给控制方案的设计带来了极大的困难。通过建立更为精确的二阶内部模型,提出了一种有效的ITCDIC内模控制方案。实例研究结果表明,与传统控制方案PID相比,控制品质更加稳定可靠;同时,与目前国际上公开报道的最好结果相比,该控制方案有更广泛的操作域,鲁棒性更强。

关键词：内部热耦合精馏塔内模控制反向响应

Dynamic Feedback Design for Nonlinear Systems via Linear Tracking with Application in Biology: From Model to Data

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Dynamic Feedback Design for Nonlinear Systems via Linear Tra...

Melt Index Prediction by Neural Soft-Sensor Based on Multi-Scale Analysis and Principal Component Analysis

第35届中国过程控制会议

作者： Jiahui Shen Xiaojun Ji xinggao liu College of Biotechnology and Pharmaceutical Engineering Nanjing Tech University

Through linear tracking method to deal with nonlinear systems, this paper proposed a dynamic state-feedback controller design method, to deal with the problem of stabilizing nonlinear systems. Under suitable assumptions on the linearized system, we prove that the proposed method can stabilize the system to the expected equilibrium state. The method can be implemented based on either model or data with high computational efficiency for only linear matrix inequalities to be solved. We make a certain extension for a more general situation, proposing the dynamic output-feedback controller design method. The effectiveness of the proposed method in nonlinear systems is illustrated through the simulation.

关键词： Feedback controller design Linear matrix inequality Linear tracking method Nonlinear system

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Chinese Journal of Chemical Engineering 2005年第6期13卷 849-852页

作者：施健刘兴高 National Laboratory of Industrial Control Technology Institute of Systems EngineeringZhejiang UniversityHangzhou 310027China

Prediction of melt index （MI）, the most important parameter in determining the product＇s grade and quality control of polypropylene produced in practical industrial processes, is studied. A novel soft-sensor model with principal component analysis （PCA）, radial basis function （RBF） networks, and multi-scale analysis （MSA） is proposed to infer the MI of manufactured products from real process variables, where PCA is carried out to select the most relevant process features and to eliminate the correlations of the input variables, MSA is introduced to a^quire much more information and to reduce the uncertainty of the system, and RBF networks are used to characterize the nonlinearity of the process. The research results show that the proposed method provides promising prediction reliability and accuracy, and supposed to have extensive application prospects in propylene polymerization processes.

关键词： propylene polymerization neural soft-sensor principal component analysis multi-scale analysis

一种求解最优控制问题的变时间节点控制向量参数化方法

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化工学报 2015年第2期66卷 640-646页

作者：李国栋刘兴高浙江大学控制系工业控制技术国家重点实验室浙江杭州310027

控制向量参数化方法是求解最优控制问题的一种常用数值方法。它通过离散化控制时域,将控制向量近似地表示成一组参数化的函数。离散化后的时间网格通常是固定的,其划分会影响到最优控制问题数值求解的精度和效率。为了同时优化控制参数... 详细信息

控制向量参数化方法是求解最优控制问题的一种常用数值方法。它通过离散化控制时域,将控制向量近似地表示成一组参数化的函数。离散化后的时间网格通常是固定的,其划分会影响到最优控制问题数值求解的精度和效率。为了同时优化控制参数和时间网格节点,提出了一种时间节点可变的控制向量参数化方法。推导出了最优控制性能指标对时间参数的导数与对时间分段长度导数之间的关系,得到了性能指标的梯度表达式。用两个经典最优控制实例对所提出的方法进行了测试,结果表明所提出方法能够更好地逼近最优控制轨迹。

关键词：过程控制控制向量参数化变时间节点优化算法

Protein complexes detecting for pharmaceutical processes control via Spectral clustering with local connectivity kernel

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Protein complexes detecting for pharmaceutical processes con...

第35届中国过程控制会议

作者： Wenjie Guo Wei Zeng Feng Li xinggao liu College of Control Science and Engineering Zhejiang University Yi Chang HEC Biochemical Pharmaceutical Co. Ltd.

Pharmacy is a complex process involving many variables. Among them, various proteins produced in the biological reaction process and protein complexes of them have an important influence on the control of pharmaceutical process. In addition, detection of protein complexes is also the most essential and fundamental problem in most Bionic manufacturing industry. However, most existing clustering technical for protein complexes detection focus primarily on the local information of the protein-protein interaction networks(PPI), which leads to the global distribution between proteins is lost and some protein complexes are further missed. Therefore, a method namely spectral clustering with improved connectivity kernel(SPICK) is proposed to detect protein complexes based on both local and global information of the protein-protein interaction networks. In SPICK, the improved connectivity kernel considers both Euclidean distance and connectivity kernel to calculate the affinity matrix, which combines local information with global distribution of PPI effectively. Experimental results show that our method performs better in comparison to existing protein complexes techniques.

关键词： protein complexes spectral clustering global distribution connectivity kernel PPI

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基于PSO_SA算法的聚丙烯熔融指数预报

化工学报 2010年第8期61卷 1955-1959页

作者：李九宝刘兴高浙江大学工业控制研究所工业控制技术国家重点实验室浙江杭州310027

实时准确的熔融指数预报在控制聚丙烯产品质量和提高聚丙烯生产的经济效益上有着举足轻重的作用。本文提出了一种粒子群优化(PSO)算法和模拟退火(SA)算法相结合的PSO_SA算法,该算法利用PSO和SA的优劣势进行互补,提高了算法寻优的能力和... 详细信息

实时准确的熔融指数预报在控制聚丙烯产品质量和提高聚丙烯生产的经济效益上有着举足轻重的作用。本文提出了一种粒子群优化(PSO)算法和模拟退火(SA)算法相结合的PSO_SA算法,该算法利用PSO和SA的优劣势进行互补,提高了算法寻优的能力和效果。利用此算法对建立的RBF聚丙烯熔融指数预报模型进行结构寻优,得到结构最优的预报模型。最后通过该模型对实际聚丙烯生产数据的预报研究,证明了PSO_SA算法寻优得到的预报模型具有很高的预报精度和可靠性能。

关键词：粒子群优化(PSO) 模拟退火(SA) RBF神经网络熔融指数预报

自适应粒子群优化算法在聚丙烯熔融指数预报上的应用

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化工学报 2010年第8期61卷 2030-2034页

作者：赵成业刘兴高工业控制技术国家重点实验室浙江大学控制科学与工程系浙江杭州310027

针对丙烯聚合生产控制中聚丙烯熔融指数在线测量的控制要求,以及过程变量间相关性高的特点,提出一种基于自适应粒子群优化算法和径向基函数神经网络的聚丙烯熔融指数预报新方法。该方法采用变参数的自适应粒子群优化算法提高优化算法的... 详细信息

针对丙烯聚合生产控制中聚丙烯熔融指数在线测量的控制要求,以及过程变量间相关性高的特点,提出一种基于自适应粒子群优化算法和径向基函数神经网络的聚丙烯熔融指数预报新方法。该方法采用变参数的自适应粒子群优化算法提高优化算法的效率和收敛性,并且融合了主成分分析、统计建模以及智能优化方法,从而降低了预报模型的复杂度。提出了一种基于径向基函数神经网络的统计预报模型的参数优化和结构优化方法。使用该统计模型对工厂实际生产过程进行预报,并与国内外相关研究报道相比较,表明了本文所提出的预报方法的有效性和更高的准确性。

关键词：聚丙烯熔融指数预报自适应粒子群优化算法径向基函数神经网络