The relations between the two tasks called Dependency, Lowery and Stover describes the task dependency as "the logical connection, or link, between two tasks", (Lowery & Stover, 2001, p. 58). These relations defined according to the tasks predecessors and successors. Wysocki states four dependencies to describe and explain the relation between two tasks (Wysocki 2012, p.204 & 205): Finish-to-start (FS), where task 2 cannot start unless the task 1 completed. Start-to-start (SS), where task 2 starts when the task 1 start. Start-to-finish (SF), where task 2 finish when task 1 starts. Finish-to-finish (FF) where task 2 finish when task 1 finished.
My example here from my specific job and so sophisticated, cementing job, for FS, we cannot mix the cement slurry unless we finished add the chemical the water, mixing fluid, and mix them properly. For SS, we start pumping cement slurry on fly when we start mixing of the mixing fluid and dry cement. For SF, when the pressure rising up this means pumping displacement fluid finished. FF, example for SS dependency can be applied here when in fly mixing cement slurry mixing finish pumping finishing.
The constraints between the tasks determine the dependencies between them. Single constrain can lead to any...