calculated_knots date distance_km distance_nm final_speed_knots geom_txt good_seg ihs_pull_date implied_speed_knots lat length_m lon mmsi num operator overlapping_and_short rgn seg_id segment_time_minutes source speed_knots speedbin_calculated_num speedbin_calculated_str speedbin_final_num speedbin_final_str speedbin_implied_num speedbin_implied_str speedbin_num speedbin_str timestamp timestamp_beg timestamp_end timestamp_lastmodified touches_shore weight_gt zone