Route Anomaly Detection Using a Linear Route Representation

Algorithm 3

Route Checking for Unordered Routes

(1) Every stored route is an available route and every sub-route

 of an available route is an available sub-route.

(2) Find the start location of the traveler in an available sub-

 routes of an available route 𝑖 and set the current line segment

 𝑖_𝑐 to the first matched segment.

(3) 𝑑₀ = the distance between the current location and the current line

 segment 𝑖_𝑐.

 𝑑₁ = the shortest distance between the current location and

 the line segment 𝑖_𝑐+1 among the ones connected to 𝑖_𝑐.

 if [𝑑₀≤𝑒 (the allowable error)], then do nothing,

 else if [(𝑑₀>𝑒) and (𝑑₁≤𝑒)], then mark the 𝑖_𝑐 unavailable and 𝑖_𝑐=𝑖_𝑐+1,

 else remove the route from the available routes. If the

 available routes are empty, report an anomaly and stop.

(4) Repeat the above step for the next location of the traveler until

 the traveler ends the route checking.