“…Figure 3 shows a sensor network (based on the river fragment of Figure 2), where the sets of sensor nodes are S = {1, 4, 8} and their times series, measuring water temperature (in degrees Celsius) at regular moments, are ts(1) = {(1, 12), (2,10), (3,8), (4,10), (5,12), (6,9), (7, 8.5), (8,8), (9, 10)}; ts(4) = {(1, 9), (2,10), (3,9), (4,10), (5,12), (6,9), (7,10), (8,11), (9,11)}; and (2,8), (3,10), (4,10), (5,9), (6,10), (7,11), (8,11), (9,12)}.…”