A diagnostic algorithm is described in this article that is based on clustering qualitative event sequences called traces. A sufficient number of training traces are used instead of an internal model to specify the faulty models of the system. The diagnosis consists of two phases. In the off-line training phase diagnostic clusters representing nominal and faulty behavior are formed from the set...

Qualitative trend analysis (QTA) is a process-history-based data-driven technique that works by extracting important features (trends) from the measured signals and evaluating the trends. QTA has been widely used for process fault detection and diagnosis. Recently, Dash et al. (2001, 2003) presented an intervalhalving-based algorithm for off-line automatic trend extraction from a record of data...

Industrial processes are large scale, highly complex systems. The flow of mass and energy, as well the compensation effects closed-loop control systems, cause significance cross-correlation autocorrelation between process variables. To operate systems stably efficiently, it is crucial to uncover inherent characteristics both variance structure dynamic relationship. Long-term dependency slow fea...

A new fault-relevant KPCA algorithm is proposed. Then the fault detection approach is proposed based on the fault-relevant KPCA algorithm. The proposed method further decomposes both the KPCA principal space and residual space into two subspaces. Comparedwith traditional statistical techniques, the fault subspace is separated based on the fault-relevant influence. This method can find fault-rel...

An RNN-based forecasting approach is used to early detect anomalies in industrial multivariate time series data from a simulated Tennessee Eastman Process (TEP) with many cyberattacks. This work continues a previously proposed LSTM-based approach to the fault detection in simpler data. It is considered necessary to adapt the RNN network to deal with data containing stochastic, stationary, trans...

In this work, we apply the systematic approach to plant-wide control design presented in [1], based on the fundamentals of process networks, thermodynamics and systems theory, to the Tennessee Eastman (TE) Challenge Process, deriving robust decentralized controllers that will ensure the stability of the complete plant. We take one step further in the control design procedure by completing it wi...

Das/Cheng/Pai/AAPM//2002 Historical Perspective 1826 Joseph Niepce First Photograph 1836 J. M. Daguerre Concept of developer 1889 Eastman Kodak Cellulose nitrate base for emulsion 1890 Hurter &Driffield Defined the term optical density 1895 Roentgen First Radiograph 1896 Carl Schlussner First glass plate for radiography 1913 Kodak Film on Cellulose nitrate base 1918 Kodak Double emulsion film 1...

Low latitude boundary layer (LLBL) can be found at low latitudes on the whole dayside magnetosphere and along magnetospheric flanks. This layer is filled by magnetosheath-like and magnetospheric plasmas. The LLBL plays a crucial role in the solar wind-magnetosphere coupling. We used measurements of the five THEMIS spacecraft that crossed the dayside LLBL on June 3, 2007. Simultaneous observatio...