SCI和EI收录∣中国化工学会会刊

›› 2008, Vol. 16 ›› Issue (5): 746-751.

• • 上一篇    下一篇

Adaptive Soft-sensor Modeling Algorithm Based on FCMISVM and Its Application in PX Adsorption Separation Process

傅永峰1, 苏宏业2, 张英3, 褚健2   

  1. 1. Modern Education Technology Center, College of Education, Zhejiang University, Hangzhou 310027, China;
    2. National Laboratory of Industrial Control Technology, Institute of Cyber Systems and Control, Zhejiang University, Hangzhou 310027, China;
    3. BI Center of Competency, IBM China SWG, Shanghai 200021, China
  • 收稿日期:2007-06-22 修回日期:2008-05-28 出版日期:2008-10-28 发布日期:2008-10-28
  • 通讯作者: SU Hongye,E-mail:hysu@iipc.zju.edu.cn
  • 基金资助:
    the National Natural Science Foundation of China(60421002);priority supported financially by“the NewCentury 151 Talent Project”of Zhejiang Province.

Adaptive Soft-sensor Modeling Algorithm Based on FCMISVM and Its Application in PX Adsorption Separation Process

FU Yongfeng1, SU Hongye2, ZHANG Ying3, CHU Jian2   

  1. 1. Modern Education Technology Center, College of Education, Zhejiang University, Hangzhou 310027, China;
    2. National Laboratory of Industrial Control Technology, Institute of Cyber Systems and Control, Zhejiang University, Hangzhou 310027, China;
    3. BI Center of Competency, IBM China SWG, Shanghai 200021, China
  • Received:2007-06-22 Revised:2008-05-28 Online:2008-10-28 Published:2008-10-28
  • Supported by:
    the National Natural Science Foundation of China(60421002);priority supported financially by“the NewCentury 151 Talent Project”of Zhejiang Province.

摘要: To overcome the problem that soft sensor models cannot be updated with the process changes,a soft sensor modeling algorithm based on hybrid fuzzy c-means(FCM)algorithm and incremental support vector machines(ISVM)is proposed.This hybrid algorithm FCMISVM includes three parts:samples clustering based on FCM algorithm,learning algorithm based on ISVM,and heuristic sample displacement method.In the training process,the training samples are first clustered by the FCM algorithm,and then by training each clustering with the SVM algorithm,a sub-model is built to each clustering.In the predicting process,when an incremental sample that represents new operation information is introduced in the model,the fuzzy membership function of the sample to each clustering is first computed by the FCM algorithm.Then,a corresponding SVM sub-model of the clustering with the largest fuzzy membership function is used to predict and perform incremental learning so the model can be updated on-line.An old sample chosen by heuristic sample displacement method is then discarded from the sub-model to control the size of the working set.The proposed method is applied to predict the p-xylene(PX)purity in the adsorption separation process.Simulation results indicate that the proposed method actually increases the model's adaptive abilities to various operation conditions and improves its generalization capability.

关键词: soft sensor, fuzzy c-means, incremental support vector machines, heuristic sample displacement method, p-xylene purity

Abstract: To overcome the problem that soft sensor models cannot be updated with the process changes,a soft sensor modeling algorithm based on hybrid fuzzy c-means(FCM)algorithm and incremental support vector machines(ISVM)is proposed.This hybrid algorithm FCMISVM includes three parts:samples clustering based on FCM algorithm,learning algorithm based on ISVM,and heuristic sample displacement method.In the training process,the training samples are first clustered by the FCM algorithm,and then by training each clustering with the SVM algorithm,a sub-model is built to each clustering.In the predicting process,when an incremental sample that represents new operation information is introduced in the model,the fuzzy membership function of the sample to each clustering is first computed by the FCM algorithm.Then,a corresponding SVM sub-model of the clustering with the largest fuzzy membership function is used to predict and perform incremental learning so the model can be updated on-line.An old sample chosen by heuristic sample displacement method is then discarded from the sub-model to control the size of the working set.The proposed method is applied to predict the p-xylene(PX)purity in the adsorption separation process.Simulation results indicate that the proposed method actually increases the model's adaptive abilities to various operation conditions and improves its generalization capability.

Key words: soft sensor, fuzzy c-means, incremental support vector machines, heuristic sample displacement method, p-xylene purity