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Network models. Forward and backward pass. Project planning Network analysis I Project planning Network analysis II. Project planning Resource analysis Risk management Quality Budgets and cost control Project teams. Plan. Introduction Project planning Gantt chart and WBS
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Network models Forward and backward pass
Project planning Network analysis I Project planning Network analysis II Project planning Resource analysis Risk management Quality Budgets and cost control Project teams Plan • Introduction • Project planning • Gantt chart and WBS • Project planning • Network analysis I • Project planning • Network analysis II
Why Network Diagrams? • Splits up the decision making process into • Method/logic - the order in which tasks have to be completed • Time – estimates for the time to completion can be added to each task • Resources – these can be added and then analysis carried out
Why Network Diagrams? • Splits up the decision making process into • Method/logic - the order in which tasks have to be completed • Time – estimates for the time to completion can be added to each task • Resources – these can be added and then analysis carried out
Two Parts to the Analysis • Forward Pass • Calculates the Duration of the Project • Backward Pass • Calculates the slack/float for each task and shows the critical path
Forward Pass In a game of rugby it is a means of cheating often missed by referees (BBC, 2005)
Forward Pass • …but in project management it is used • To calculate the total duration of the Project… • For each task: • Take the earliest start time (EST) • Calculate the Earliest finish time (EFT): EFT = EST+Duration
Exercise 1 – Forward Pass • Carry out a forward pass on Project in Exercise 1
Project Exercise 1 Dangler Dangler Dangler
Backward Pass • To calculate the float for each task? • For each task: • Take the latest start time (LST) • Calculate the latest finish time (LFT): LST = LFT-Duration
Exercise 1 – Backward Pass • Carry out a backward pass on project exercise 1
What about the float? • Float = LFT-EFT • Or • Float = LST-EST
What about the float? • Float represents the amount of time that the task can be delayed without affecting the outcome of the project • A task with zero float cannot be delayed and is therefore critical to the timely completion of the project
What about the float? • A time optimised project will have a sequence of tasks from start to finish that have zero float • This sequence of tasks is called the critical path
Exercise 1 – Critical Path • Calculate the float for each task and identify the critical path through the project
Questions • My Project has no critical path. What does this mean? • My programmer has broken his big toe in a skiing accident and cannot type for two weeks (he has a valid sick note). How will this affect my software delivery date?
Directed Study • Find the critical path for Project Exercise 2 (see Lecture 3). • Find the critical path for the large project in Exercise 3.
Project planning Network analysis I Project planning Network analysis II Project planning Resource analysis Risk management Quality Budgets and cost control Project teams Plan • Introduction • Project planning • Gantt chart and WBS • Project planning • Network analysis I • Project planning • Network analysis II • Project planning • Resource analysis • Risk management • Quality • Budgets and cost control • Project teams