4. Project Planning Phase
4.9 D EVELOP S CHEDULE
Figure 4-20- 6.5 Develop Schedule Process Source: PMBOK® Guide - Fourth Edition, page 152 1. Activity list
2. Activity attributes 3. Project schedule network diagrams 4. Activity resource
requirements 5. Resource calendars 6. Activity duration
estimates 7. Project scope
statement 2. Critical path
method 3. Critical chain
method 4. Resource
leveling
5. What-if analysis 6. Applying leads
and lags
Develop Schedule is the process of analyzing activity sequences, durations, resource requirements, and schedule constraints to create the project schedule.
Source: PMBOK® Guide – Fourth Edition, page 152
4- Planning Phase
PMP Exam Preparation Course Page 86
Process Interaction
Ø Organizational process assets Ø Enterprise
environmental factors
Ø Project Documents Updates Ø Project schedule
network diagrams Ø Activity list Ø Activity attributes
Involved Documents (IN) ØActivity list
ØActivity attributes ØProject schedule network
diagrams 5.2 Define Scope 9.2 Acquire
Project Team
Ø Project Scope Statement
Ø Project Schedule Ø Activity duration
estimates Ø Activity resource
requirements
Ø Schedule data
Ø Resource Calendars
Ø Schedule baseline
Source: PMBOK® Guide – Fourth Edition Diagram Developed by Techno Management Ø
Figure 4-21- Develop Schedule – Process Interaction
Schedule Constraints
Two categories of constraints are directly related to scheduled development:
Imposed Dates, they are:
- Key Events - Major Milestones Example of Constraints:
Constraint Type Description
Start No Later Than The task must start before or on
that date.
Start No Earlier Than The task may not start before this
date.
Finish No Later Than The task must be completed by
that date.
Finish No Earlier Than The task may not be completed
before this date.
4.9.1 Inputs to Develop Schedule 1. Activity list
2. Activity attributes
3. Project schedule network diagrams
4- Planning Phase
PMP Exam Preparation Course Page 87
4. Activity resource requirements 5. Resource calendars
6. Activity duration estimates 7. Project scope statement
8. Enterprise environmental factors 9. Organizational process assets Project Calendars
Project and resource calendars identify when work is allowed. They affect all resources. Resource calendars affect only that resource or group of resources.
4.9.2 Tools and Techniques for Develop Schedule 1. Schedule network analysis
2. Critical path method 3. Critical chain method 4. Resource leveling 5. What-if analysis
6. Applying leads and lags 7. Schedule compression 8. Scheduling tool
1. Schedule network analysis
Schedule network analysis is a technique that generates the project schedule. It employs various analytical techniques, such as:
Critical path method
Critical chain method
What-if analysis
Resource leveling
2. Critical path method
The critical path method calculates the theoretical early start and finish dates and late start and finish dates without regard for any resource
4- Planning Phase
PMP Exam Preparation Course Page 88
Free Float: is the amount of time that an activity can be delayed without delaying the early start of any immediately following activities.
Calculating Path and Float Forward Pass:
Early Start (ES) = Total of task durations for all precedent (necessary) tasks
Early Finish (EF) = ES + Task Duration Backward Pass:
Late Finish (LF) = Last day of project – Duration of sequential (necessary) tasks to end of project
Late Start (LS) = LF – Task Duration Float = LF – ES – Task Duration
Task Coding Convention - Early Start = ES - Early Finish = EF - Late Start = LS - Late Finish = LF - Duration = DU Process
a. Construct the Network Diagram b. Apply the Task Duration
c. Calculate the Forward Pass d. Calculate the Backward Pass e. Calculate Floats
a. Construct the Network Diagram
EF
LS LF
ES
DU
4- Planning Phase
PMP Exam Preparation Course Page 89
b. Apply the Task Duration
c. Calculate the Forward Pass
d. Calculate the Backward Pass
58
4- Planning Phase
PMP Exam Preparation Course Page 90
61
C
5
9 10
4
1
B
4
6 9
1
3
A
1
0 1
0
1
F
13
7 13
7
6
E
7
1 7
1
6
D
10
10 13
7
3
G
15
13 15
13
2
4- Planning Phase
PMP Exam Preparation Course Page 91
e. Calculate Floats
3. Critical chain method
The critical path methods calculates the theoretical early start and finish dates, and late start and finish dates without regard for any resource limitations. This is done by performing a forward and backward pass analysis through the schedule network. The resulting early and late start and finish dates are not necessarily the project schedule; rather they indicate the time periods within which the activity could be scheduled.
4. Resource leveling
Resource leveling is necessary when resources are over-allocated such as when the resource is:
- Assigned to two or more activities during the same time period - Shared or critical required resources are only available at certain
times
- Only available in limited quantities.
Resource leveling can often cause the original critical path to change.
It mostly results in extended schedule
Figure 4-22- Resource Leveling
63
4- Planning Phase
PMP Exam Preparation Course Page 92
5. What-if analysis
This is based on the calculation of multiple project durations with different sets of activity assumptions. “What-if analysis” using the logic in the network diagram. A well known technique of “What if analysis” is called Monte Carlo Analysis, it is:
- The most common technique.
- Distribution of probable results is defined for each activity, and then used to determine the distribution of probable results for the total project.
- Also used in Project Risk Management
6. Applying leads and lags
A lead allows an acceleration of the successor activity, while a lag directs a delay in the successor activity
7. Schedule compression
The two main techniques that are used to compress schedules are:
a- Fast tracking: A schedule compression technique in which phases or activities normally performed in sequence are performed in parallel.
b- Crashing: It is a schedule compression technique in which cost and schedule tradeoffs are analyzed to determine how to obtain the greatest amount of compression for the least incremental cost.
8. Scheduling tool
MS Project
Primavera
4.9.3 Outputs of Develop Schedule 1. Project schedule:
- Milestones charts - Bar charts
- Project schedule network diagrams 2. Schedule baseline
3. Schedule data
4. Project document updates:
- Activity resource requirements - Activity attributes
- Calendar - Risk register
4- Planning Phase
PMP Exam Preparation Course Page 93
Exercise 4-9- Develop Schedule
Exercise 4.9 – Develop Schedule
The following information and questions 1 through 9 refer to below network diagram
Assume that the work is on a single shift basis and will seven days per week until the job is done. The project is to begin on May 1.
B
H E
C A
F D
G
3
FS-2
1
3 4
5 4
2
7
1. What day in May will activity D have for its early finish date?
2. What is the free float for activity F?
3. What is the free float for activity D?
4. What is the critical path of the project?
5. What is the late start for activity F?
6. How long is the project in days?
7. What is the early start for activity F?
8. If there is a delay in activity F of six days, what is the effect on the project completion date?
9. What is the early finish date of activity A?
4- Planning Phase
PMP Exam Preparation Course Page 94