Abstract:Data-driven soft sensors provide a potentially cost-effective and more accurate modeling approach to measure difficult-to-measure indices in industrial processes compared to mechanistic approaches. Artificial intelligence (AI) techniques, such as deep learning, have become a popular soft sensors modeling approach in the area of machine learning and big data. However, soft sensors models based deep learning potentially lead to complex model structures and excessive training time. In addition, industrial processes often rely on distributed control systems (DCS) characterized by resource constraints. Herein, guided by spatial geometric, a lightweight geometric constructive neural network, namely LightGCNet, is proposed, which utilizes compact angle constraint to assign the hidden parameters from dynamic intervals. At the same time, a node pool strategy and spatial geometric relationships are used to visualize and optimize the process of assigning hidden parameters, enhancing interpretability. In addition, the universal approximation property of LightGCNet is proved by spatial geometric analysis. Two versions algorithmic implementations of LightGCNet are presented in this article. Simulation results concerning both benchmark datasets and the ore grinding process indicate remarkable merits of LightGCNet in terms of small network size, fast learning speed, and sound generalization.
Abstract:Incremental random weight neural networks (IRWNNs) have gained attention in view of its easy implementation and fast learning. However, a significant drawback of IRWNNs is that the elationship between the hidden parameters (node)and the residual error (model performance) is difficult to be interpreted. To address the above issue, this article proposes an interpretable constructive algorithm (ICA) with geometric information constraint. First, based on the geometric relationship between the hidden parameters and the residual error, an interpretable geometric information constraint is proposed to randomly assign the hidden parameters. Meanwhile, a node pool strategy is employed to obtain hidden parameters that is more conducive to convergence from hidden parameters satisfying the proposed constraint. Furthermore, the universal approximation property of the ICA is proved. Finally, a lightweight version of ICA is presented for large-scale data modeling tasks. Experimental results on six benchmark datasets and a numerical simulation dataset demonstrate that the ICA outperforms other constructive algorithms in terms of modeling speed, model accuracy, and model network structure. Besides, two practical industrial application case are used to validate the effectiveness of ICA in practical applications.