Description of common OSPF logs on S series switches

What do the following OSPF logs indicate?
The logs are described as follows:

Feb 13 2009 17:10:52 LL-NE40E-1 %%01OSPF/3/NBR_CHG_DOWN(l): Neighbor event:neighbor state changed to Down. (ProcessId=1, NeighborAddress=, NeighborEvent=InactivityTimer, NeighborPreviousState=Full, NeighborCurrentState=Down)
Log description: The status of the neighbor of which the IP address is turns from Full to Down due to InactivityTimer, which indicates that the switch does not receive a Hello keepalive packet from the neighbor within the period specified by DeadInterval.
The following causes also lead to changes in neighbor status.
KillNbr: An interface goes Down, the BFD session becomes Down, or a process is reset.
LLDown: A VLANIF, trunk, or serial port becomes Down.
SeqNumberMismatch: An error occurs when the two switches exchange routing information, or due to link transmission delay, the neighbor receives a Hello packet sent by the local switch after the neighbor relationship is interrupted and sends the local switch a DD packet. When the local switch in the Full state receives the DD packet, the event occurs.

May 10 2009 14:13:00 R13 %%01OSPF/6/NBR_CHANGE_E(l): Neighbor changes event: neighbor status changed. (ProcessId=1, NeighborAddress=, NeighborEvent=1-Way, NeighborPreviousState=Full, NeighborCurrentState=Init)
Log description: The status of the neighbor of which the IP address is turns from Full to Init due to 1-Way, which indicates that the switch receives a Hello packet from the neighbor that requires initializing the neighbor relationship.
The OSPF neighbor status on the neighbor switch turns Down, the neighbor then sends an initialization packet to the local switch, and the local switch disconnects the neighbor relationship after receiving the packet. The log is generated.

May 12 2009 14:23:58 R13 %%01OSPF/6/IF_CHG_E(l): Interface received event InterfaceDown, interface state changed from DR to Down. (Process ID=1)
Log description: The status of the interface with the IP address turns from DR to Down due to an interface Down event. For example, the physical interface goes Down.
The following cause also leads to changes in interface status.
NeighborChange: Generally, after the status of an interface on a broadcast network turns from DR to Down, the BDR becomes the DR.

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