UA 3851 then DL 1995 at Houston
Seoul → Houston → Atlanta
Timetable, Houston time
17:54UA 3851 from Seoul at the gate
16:55DL 1995 to Atlanta leaves the gate
23 h 01 apart on the timetable, overnight
DL 1995 leaves 23 h 01 after UA 3851 arrives on the timetable: more than half a day, so not a connection we count.