key	tag	start	end	length(seg)	device	br_mean
1	ON	19:02:56	19:13:56	660.0	mobile	0.239393939394
2	ON	19:18:56	19:25:50	414.0	mobile	0.0845410628019
3	ON	18:30:02	21:29:58	10796.0	pc	2230.43821786
4	ON	18:49:00	21:21:27	9147.0	pc	2252.43183557
5	ON	18:44:30	18:57:00	750.0	pc	2526.38