Project Scheduling

Common terminology :

Early start- Early time in which an activity can start.
 Late start- Latest time by which an activity can start.
Early Finish- Earliest time in which an activity can finish.
Late finish- Latest time by which an activity can finish.
Optimistic Time: earliest time in which an activity can finish if no hurdles or complications arises.
Pessismistic Time: Maximum duration in which an activity can finish if any complications arises.
Most likely Time : Mid duration taken between Optimistic time and Pessismistic time.
Expected Complition Time: (optimistic time + (4*most likely time) + pessismistic time)/ 6
EOT(Early Occurance Time): Time in which event has been completed earliest.
Its computation procedure is refered to as FORWARD PASS.
LOT (Late Occurance Time) :Latest allowabletime in which an event can occur.
Computed by BACKWARD PASS: by moving in backward direction from end node.

PERT-(Project Evaluation and Review Technique)
# can determine slack
# time based analysis 
# can manage uncertain activites
#probalistic 
#focus on event
# suitable for research and development programs


CPM - (Critical path method)
# can't determine slack 
#cost based analasis
# can manage well defined activity
#deterministic
# focus on activity
# suitable for project like civil engineering project , ship project ...

# critical path is the longest path along with feasible time and the node appearing in the critical path are called critical node.