This book proposes tools for analysis of multidimensional and metric
data, by establishing a state-of-the-art of the existing solutions and
developing new ones. It mainly focuses on visual exploration of these
data by a human analyst, relying on a 2D or 3D scatter plot display
obtained through Dimensionality Reduction.
Performing diagnosis of an energy system requires identifying relations
between observed monitoring variables and the associated internal state
of the system. Dimensionality reduction, which allows to represent
visually a multidimensional dataset, constitutes a promising tool to
help domain experts to analyse these relations. This book reviews
existing techniques for visual data exploration and dimensionality
reduction such as tSNE and Isomap, and proposes new solutions to
challenges in that field.
In particular, it presents the new unsupervised technique ASKI and the
supervised methods ClassNeRV and ClassJSE. Moreover, MING, a new
approach for local map quality evaluation is also introduced. These
methods are then applied to the representation of expert-designed fault
indicators for smart-buildings, I-V curves for photovoltaic systems and
acoustic signals for Li-ion batteries.