Table 2: List of notations.

Notation Explanation Notation Explanation R The CPS dataset , The atypical data records S The sensor set , The sensors T The time period , The time windows SF The spatial feature TF The temporal feature The severity measure The total severity The atypical events The spatial region The analytical query The atypical clusters The agg. severity by The agg. severity by The time threshold The distance threshold The severity threshold The similarity threshold