tailieunhanh - Fundamentals of Project Management Worksmart by James P. Lewis_6

Tham khảo tài liệu 'fundamentals of project management worksmart by james p. lewis_6', kinh doanh - tiếp thị, quản trị kinh doanh phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | I Producing a Workable Schedule 97 Figure 8-2. Diagram with EF times filled in. are called forward-pass computations to determine Earliest Finish times for all activities. Computer programs do exactly the same thing and additionally convert the times to calendar dates making quick work of the computations. RULE When two or more activities precede another activity the earliest time when that activity can be started is the longer of the durations of the activities preceding it. NOTE The time determined for the end or final event is the earliest finish for the project in working time. Once weekends holidays and other breaks in the schedule are accounted for the end date may be considerably later than the earliest finish in working time. Backward-Pass Computations A backward pass is made through the network to compute the latest start and latest finish times for each activity in the network. To do that we must decide how late the project can finish. By convention we generally don t want a project to end any later than its earliest possible completion. To stretch it out longer would be inefficient. American Management Association 98 Fundamentals of Project Management I When doing backward-pass calculations always use the smallest num- ber for the LF of previous activities. We also won t insist for now that the project end earlier than the earliest possible finish calculated in the previous steps. If we want to finish earlier we will have to redraw the network or shorten some activities . by applying more resources or working more efficiently . For now we will accept the 165-minute working time and let it be the Latest Finish for the project. If Hauling Away Trash has a Late Finish of 165 minutes and has a duration of 45 minutes what is the latest that it could start Clearly if we subtract 45 from 165 we have 120 minutes which is the Latest Start for the task. Proceeding in this manner we get LS times for Bagging Grass and Bundling Clippings of 90 and .