Sensors Anomaly Detection of Industrial Internet of Things Based on Isolated Forest Algorithm and Data Compression

Algorithm 1

Sensor data compression algorithm.

	Input: data.txt sensor data T number of packets processed in a single group K, error threshold E.
Output: out1.txt, out2.txt.
(1)	for i = 1 to N
(2)	read the data from “test.txt”, and write them to “data.txt”
(3)	if e of the “test.txt”
(4)	break
(5)	end if
(6)	for i = 1 to N
(7)	read the data from “data.txt” to T[i + 1]
(8)	aver = sum(T)/i + 1;
(9)	end
(10)	if (aver < 0)
(11)	for i = 1 to k
(12)	aver < aver + T[i]
(13)	aver < aver/k
(14)	end
(15)	else
(16)	for i = 2 to n
(17)	temp < aver
(18)	for j = 0 to k − 1
(19)	if i + j ≥= n
(20)	temp < −1
(21)	aver < aver + T[i + j]
(22)	end if
(23)	end
(24)	end if
(25)	end
(26)	end if
(27)	aver < aver/k
(28)	if |aver-temp| >= e
(29)	put i + j −1 to “out1.txt”
(30)	put T[i + j −1] to “out2.txt”
(31)	end if
(32)	return “out1.txt”,“out2.txt”