Transcript Document

16.1
Project Planning & Control
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Operations Management, 4E: Chapter 16
16.2
Chapter Coverage
• What is a project?
• The project planning and control process
• Network planning – Critical Path Method (CPM)
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Operations Management, 4E: Chapter 16
16.3
Projects:
A project is a set of activities with a define start
point and a define end state, which pursues a
defined goal and uses a define set of resources.
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Operations Management, 4E: Chapter 16
16.4
Stages in project management
Stage 1
Understanding
the project
environment
Stage 2
Project
definition
Changes
Project
planning
Corrective action
Stage 3
Stage 5
Stage 4
Technical
execution
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Project
control
Operations Management, 4E: Chapter 16
16.5
Stage 1: Understanding project environment
The project environment comprises the
factors which may affect the project during
its life. See slide 16.6
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Operations Management, 4E: Chapter 16
16.6
Geo-social environment
• Geography
• National culture
Econo-political environment
• Economy
• Government
The Project
Business environment
• Customers
• Competitors
• Suppliers/sub-contractors
Internal environment
• Company strategy
• Resources
• Other projects
Examples of factors that may affect the project
environment
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Operations Management, 4E: Chapter 16
16.7
Stage 2: Project definition
Three different elements define a project:
• Its objective: the end state that project
management is trying to achieve
• Its scope: the exact range of the responsibilities
taken on by the project management.
• Its strategy: how project management is going to
meet its objective.
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Operations Management, 4E: Chapter 16
16.8
Project objectives
The hierarchy of objectives:
• At the top of the hierarchy is the overall
objective or goal of the project, lower levels of
the hierarchy are the objectives of each part of the
project (big projects consists of many parts).
• Objectives of each part must be related to its
overall objective.
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Operations Management, 4E: Chapter 16
16.9
Objectives must be clear:
Good objectives are those which are clear, measurable and,
preferably, quantifiable.
One method of clarifying objectives is to break down project
objectives into three categories:
– Purpose: to prevent production from failing to meet
output as forecast.
– End result: a report which identifies the causes of lost
production, and which recommends how the target output
can be met.
– Success criteria: the report should be completed by 30
June. The recommendations should enable output to reach
at east 70 tonnes per year. Cost of the recommendations
should not exceed RM200,000.
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Operations Management, 4E: Chapter 16
16.10
The three project performance objectives
Quality
New aircraft
project
Fixed grant
research
project
Cost
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Music
festival
Time
Operations Management, 4E: Chapter 16
16.11
Project scope
- Identifies the work content and the outcomes.
- Boundary setting exercise – divides work
content for each part of the project.
- Important for managing contractors –
commercial and legal aspect of the scope of
supply.
- Can change during the course of the project.
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Operations Management, 4E: Chapter 16
16.12
Project strategy
-
-
Defines in general how the organization is
going to achieve its project objectives and
meet the related measure of performance.
Two ways:
1) Define phases (time based sections) of the
project.
2) Set milestones at which specific reviews of time,
cost and quality are made.
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Operations Management, 4E: Chapter 16
16.13
Stage 3: Project planning
Fulfills four distinct purpose, it determines:
1.
2.
3.
4.
The cost and duration of the project.
The level of resources needed.
Helps to allocate work and monitor progress.
Helps to assess the impact of changes to the
project.
There are five steps…
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Operations Management, 4E: Chapter 16
16.14
Stages in the project planning process
Adjust as necessary
Identify
the
activities
in the
project
Estimate
the times
and
resources
for
activities
1
2
Identify the
relationships
and
dependencies
between the
activities
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
3
Identify
time and
resource
schedule
constraints
Fix the
schedule
for time
and
resources
4
5
Operations Management, 4E: Chapter 16
16.15
1. Identify activities: Work breakdown structure
1. Serve
breakfast in bed
2. Pour juice
in glass
3. Fetch
juice
4. Fetch
glass
5. Place
boiled egg in
egg cup
6. Boil egg
10.
Fetch
egg cup
11. Butter
the toast
12. Toast
bread
15. Fetch
butter
16. Arrange
tray
17. Fetch
tray, plates
and cutlery
13. Slice
bread
7.
Fetch
egg
8. Bring
water to
boil
14.
Fetch
bread
9. Fill pan
with water
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Operations Management, 4E: Chapter 16
2. Estimate times and resources
16.16
Table 16.1
Time and resources estimates for a breakfast-in-bed” project
No
Activity
Effort (person)
Duration (secs)
1
Serve breakfast in bed
1
120
2
Pour juice in glass
1
5
3
Fetch juice
1
10
4
Fetch glass
1
10
5
Place boiled egg in egg cup
1
3
6
Boil egg
0
240
7
Fetch egg
1
10
8
Bring water to boil
0
180
9
Fill pan with water
1
8
10
Fetch egg cup
1
10
11
Butter the toast
1
10
12
Toast bread
0
30
13
Slice bread
1
30
14
Fetch bread
1
10
15
Fetch butter
1
10
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Operations Management, 4E: Chapter 16
16.17
Typical subjective probability distribution
for an activity time estimate
Probability
Accuracy of estimates
comes with experience!
3
5 6 Activity duration 13
Optimistic time
Expected time
Most likely time
Pessimistic time
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Operations Management, 4E: Chapter 16
16.18
3. Identify relationship and dependencies
• All activities will have some relationship with
one another.
• Dependent or series relationship or
1 Slice bread
2 Fill pan with water
Toast bread
Bring water to boil
• Parallel relationship
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
1 &
Butter toast
Boil egg
2
Operations Management, 4E: Chapter 16
16.19
4. Identify schedule constraints
• Resource constrained – only the available
resource level are used in resource scheduling
and are never exceeded hence, project
completion might slip.
• Time constrained – priority is to complete the
project within a given time.
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Operations Management, 4E: Chapter 16
“Making breakfast” - Do activities at
earliest time
16.20
0
1
2
Time (mins)
4
5
3
6
7
8
9
Orange
Bread
Toast
Activities requiring
operator time
Butter
Boil water
Water
Bed
room
Boil egg
Staff required
Tray
4
3
2
1
0
0
1
2
3
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
4
5
Time (mins)
6
7
8
9
Operations Management, 4E: Chapter 16
“Making breakfast” – Minimizing staff
requirements
16.21
0
1
2
Time (mins)
4
5
3
6
7
8
9
Orange
Bread
Toast
Butter
Boil water
Water
Bed
room
Boil egg
Staff required
Tray
4
3
2
1
0
0
1
2
3
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
4
5
Time (mins)
6
7
8
9
Operations Management, 4E: Chapter 16
16.22
5. Fix the schedule
“Making breakfast” – Maximizing toast
quality
0
1
2
3
Time (mins)
4
5
6
7
8
9
Orange
Bread
Boil water
Staff required
Water
Toast
Butter
Bed
room
Boil egg
Tray
4
3
2
1
0
0
1
2
3
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
4
5
Time (mins)
6
7
8
9
Operations Management, 4E: Chapter 16
16.23
Stage 5: Project control
1.
Project monitoring: current expenditure to date, amount of
overtime authorized, inspection failure, progress of activities
etc.
2.
Assessing project performance: Compare planned and
actual expenditure
3.
Intervene to change the project: when the project is out of
control in the sense of cost, quality levels or time,
intervention is required.
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Operations Management, 4E: Chapter 16
16.24
Network planning
1. Use of Gantt chart is the simplest technique that
supports project planning and control.
2. More elaborate and detailed techniques are
collectively called network analysis.
3. We will consider a network analysis method called
Critical Path Method (CPM)
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Operations Management, 4E: Chapter 16
16.25
Critical Path Method
1.
2.
3.
Represents the project activities diagrammatically.
Project activities are represented by arrows (See 16.26).
At the tail (start) and head (finish) of each activity is a circle
which represents and event (See 16.27).
Rules for drawing a network diagram:
1. An event cannot be reached until all activities leading to it
are complete - (16.27 – event 5 is not reached until c and e
are completed).
2. No activity can start until its tail event is reached - (16.27 –
activity f cannot start until event 5 is reached).
3. No two activities can have the same heat and tail events
(16.28 – activities x and y cannot be drawn as first shown,
they must be drawn using a dummy activity (no duration and
shown as a dotted line)
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Operations Management, 4E: Chapter 16
16.26
Activities and network for a simple project
Activity
a
b
c
d
e
f
Remove furniture
Prepare bedroom
Paint bedroom
Prepare kitchen
Paint kitchen
Replace furniture
Remove furniture
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Immediate
predecessors
None
a
b
a
d
c, e
Activity duration
(in days)
1
2
3
1
2
1
Replace furniture
Operations Management, 4E: Chapter 16
16.27
Network diagram for simple decorating project
Activity reference
a
Activity duration
1
EET – the very earliest the event could possibly
occur if all preceding activities are completed as
early as possible.
LET – the latest time that the event could possibly
take place without delaying the whole project
1
Event number
3
An Event
1
a
2
b
c
2
3
5
1
Earliest Event
Time (EET)
Latest Event
Time (LET)
f
6
1
d
e
1
2
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
4
Operations Management, 4E: Chapter 16
Activity on arrow – Using “dummy”
activities
16.28
2
x
x
2
1
1
3
y
y
1
3
5
2
4
6
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Operations Management, 4E: Chapter 16
16.29
Critical Path
–
Network diagrams have more that one sequence of
activities which will lead from the start to the end of the
project – these sequence are called paths.
–
Each path has a total duration which is the sum of all its
activities.
–
The path which has the longest sequence of activities is
called the critical path.
–
It is called the critical path because any delay in and of the
activities on this path will delay the whole project.
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Operations Management, 4E: Chapter 16
16.30
Network analysis for simple decorating project
With earliest and latest event times
3
3
1
0
2
a
0
1
1
3
b
c
2
3
1
Chapter 16, Page 575
5
6
d
e
1
2
4
2
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
6
f
6
1
7
7
4
Operations Management, 4E: Chapter 16
16.31
Worked Example
• The chief surveyor of a firm that moves earth
in preparation for the construction of roads has
identified the activities and their durations for
each stage of an operation to prepare a difficult
stretch of motorway (see table below). The
surveyor needs to know how long the project
will take and which are the critical activities.
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Operations Management, 4E: Chapter 16
Road Construction Activities
16.32
Activity
Duration
Preceding activities
A
5
-
B
10
-
C
1
-
D
8
B
E
10
B
F
9
B
G
3
A, D
H
7
A, D
I
4
F
J
3
F
K
5
C, J
L
8
H, E, I, K
M
4
C, J
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Operations Management, 4E: Chapter 16
16.33
Network Diagram For Motorway Project
18
A
D
5
0 0
B
10
10
C
1
H
8
7
E
10
10
9
G
3
20
27
F
27
L
8
35
35
I
4
K
19
19
3J
22
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
5
M
4
22
Operations Management, 4E: Chapter 16
16.34
The End
© Nigel Slack, Stuart Chambers & Robert Johnston, 2004
Operations Management, 4E: Chapter 16