no idea why your system shut down. EMS is Event Monitoring System that monitors the hardware (or at least generates messages for hardware problems. You can run the command specified from all (?) runlevels, just be sure the filesystems needed are mounted.
There is not really enough detail in syslog.log to determine the cause of the system shutdown.
Firstly check /etc/shutdownlog for any entries. System panics will usually write to this file.
There should also be a crash dump in /var/adm/crash and there should also be some files in /var/tombstones that can used for analysis (eg ts99).
Analysing the reason for a system crash usually requires some in depth knowledge of HP-UX. If your system has crashed you should log a call with HP or whichever organisation provides support for your systems.
There are multiple reasons for system crashes such as hardware failures (HPMC)or software failures which initiate a system PANIC.
Yes that is telling you someone shutdown the system at 11:39 on Sun 20 June. Is this the last entry in /etc/shutdownlog?? It appears your system was also shutdown on June 25?? Check /var/adm/crash for entries.
That means somebody shutdown the system, not reboot. Check the crontab file for any entries. If you don't know who did it after not finding anything, change your root password, and check any entries in your sudo file and wait to see who complains. Also have a look in the /var/adm/sulog for valid entries around the same time.
