摘要
针对污水处理过程中存在的多变量耦合、强非线性以及参数时变等问题,提出基于多核学习相关向量机的软测量建模方法,并采用粒子群算法对多核权重以及核参数进行优化。同时,引入时间差分(time difference)方法改进多核相关向量机的动态特性。为了验证所提模型的有效性,通过一仿真案例与单核相关向量机、多层前馈神经网络和基于遗传算法的支持向量机进行对比研究。结果表明,所提模型具有更好的预测效果。最后,对模型的鲁棒性在数据漂移和异常的场景下进行了讨论。
Considering the characteristics of strong multivariable coupling, significant non-linearity and parameter time-varying in the wastewater treatment processes, a multi-kernel relevance vector machine(MRVM) is proposed for soft-sensor modeling. Particle swarm optimization algorithm is further used to optimize multi-kernel weights and kernel parameters. Meanwhile, the time difference(TD) method is introduced to improve the dynamic characteristics of MRVM. The proposed model was demonstrated through a WWTP simulated case study by comparison with relevance vector machine(RVM) with a single kernel, back propagation(BP) neural network and the genetic algorithm-based support vector machine(GA-SVM). Results showed that the proposed model achieved better prediction accuracy. Finally, the robustness of the models is discussed in the context of data drift and anomalies.
引文
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