Ben Fei, Jinbai Liu
IEEE Transactions on Neural Networks
This paper addresses the task of anomaly diagnosis when the underlying data generation process has a complex spatio-temporal (ST) dependency. The key technical challenge is to extract actionable insights from the dependency tensor characterizing high-order interactions among temporal and spatial indices. We formalize the problem as supervised dependency discovery, where the ST dependency is learned as a side product of multivariate time-series classification. We show that temporal positional encoding used in existing ST transformer works has a serious limitation in capturing higher frequencies (short time scales). We propose a new positional encoding with a theoretical guarantee, based on discrete Fourier transform. We also propose a new ST dependency discovery framework, which can provide readily consumable diagnostic information in both spatial and temporal directions. Finally, we demonstrate the utility of the proposed model, DFStrans (Diagnostic Fourier-based Spatio-temporal Transformer), in a real industrial application of building elevator control.
Ben Fei, Jinbai Liu
IEEE Transactions on Neural Networks
Fahiem Bacchus, Joseph Y. Halpern, et al.
IJCAI 1995
Leonid Karlinsky, Joseph Shtok, et al.
CVPR 2019
Barry K. Rosen
SWAT 1972