Work is measured in proofs of work. Each proof of work is given a score equal to one divided by the difficulty at the time it was submitted. Proofs of work are grouped in shifts. A shift is completed when its total score passes 0.1. Whenever new coins are minted, they are divided between contributing members proportionally to the total score each member has within the last 10 completed shifts. If you are logged in you can see your score in each shift.
All timestamps are in Coordinated Universal Time (UTC).