Signal Representation by Fuzzy Triangular Episodes

The analysis of process signals may be facilitated if the time series data can be cast into a symbolic form. The relevant trends and generic data features can then be extracted and monitored using this qualitative representation. Such a transformation is often carried out by defining a set of primitives (alphabet) that define a visual characteristic of the signal [78, 142, 247]. Here, the methodology proposed by Stephanopoulos and coworkers is discussed [9, 34, 35]. They treated the problem of trend representation graphically 

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