Yes, you can. Use this command:
/gamerule doDaylightCycle false
and then set the time to whatever you wish using:
/time set (INSERT TIME HERE)
(0 for morning, 6000 for afternoon, 12000 for the beginning of night and 18000 for midnight)
For future record, though, this post is in the wrong section. This section is for published maps. If you wish to discuss maps or mapmaking, post inside Maps Discussion. Thanks!