Chapter 6
Project Implementation and Tools
Tools for Project Scheduling
The project manager uses a planning and scheduling process because most projects are
complex, of long duration, require visualization of their parts and the resources needed.
A planning and scheduling process:
•
•
•
•
Identifies project activities (tasks/steps)
Identifies the sequence and duration of project activities
Organizes project resources (labor, equipment, materials, technology, facilities)
Enables monitoring of project progress
In any project:
There will be many tasks to accomplish.
Tasks have to go through a sequence
Some tasks cannot start until others are finished (task dependency)
Some tasks are unconstrained.
Some are “critical tasks”
Some task will have flexibility in time, cost, resources
Some tasks will have uncertainty
Project scheduling involves determination of precedence relationship between work
elements(activities) determining extent of interdependency and developing the flow path of the
activities to reach the objectivities of the project.
Steps in Project Scheduling
1. Develop Work Breakdown Structure(WBS) to establish work elements constituting the
project
2. Determine Interdependency among various work elements or activities/tasks and
accordingly define logical sequence of the activities
3. Quantify each work element in terms of time/other resources requirements
4. Find out constraints, if any, external(e.g., Government policies, law and order problem,
inadequacies of infrastructure etc.). and internal(e.g., poor choice of site, inadequacies in
agreement with other stakeholders such as consultants etc.)
5. Review the work elements, their inter dependencies and quantification in light of the
identified constraints
6. Develop a flow path of activities satisfying the logic of interdependency and constraints
7. Develop a time schedule of activities satisfying the logic of the flow path and time
duration of the activities.
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Work Breakdown Structure (WBS)
First step toward a work plan
Helps to identify the tasks in a project
The concept of the WBS is simple: in order to manage a whole project, one must
manage and control each of its parts
What is a Work Breakdown Structure?
◙ The WBS is a graphical display of the project.
◙ WBS is a hierarchical listing of the sub-components of a project
◙ What is the purpose of the WBS?
The purpose of the WBS is to divide the total project into small pieces, sometimes called
work packages.
Dividing the project into work packages makes it possible to prepare project schedules
and cost estimates and to assign management and task responsibility
WBS components
Tasks
Dependencies
Start date
Duration
Resources
Milestones
Deliverables
The WBS should be divided into tangible deliverable items (hardware items, software
packages, interim reports in R & D, etc.).
WBS levels?
Typically 6 or fewer
1 Total project
2 Sub-project
3 Combination of tasks
4 Task
5 Sub-task
6 Individual processes or actions
At what level do you stop?
• Stop when you reach a point at which you can estimate required resources to the desired
degree of accuracy
• Or when the work will take an amount of time equal to the smallest units you want to
schedule days, weeks, months, etc.
• Or stop when the element is .5 to 2.0% of the project.
• Or stop once you’ve identified a “work package”
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A WBS planning key!!
REMEMBER the rule that the people who must do the work should participate in
planning it.
• Different levels may be done by different groups
– Top management may do the first level or two and pass it on down to the
operating levels for further amplification
– Software can help
A Gantt chart is a horizontal bar chart developed as a production control tool in 1917 by Henry
L. Gantt, an American engineer and social scientist. Frequently used in project management, a
Gantt chart provides a graphical illustration of a schedule that helps to plan, coordinate, and
track specific tasks in a project. It is a simple and widely used method of working out and
displaying the knotty problem of who does what and when. Typically it is used in a project
where a number of people are working on interlinked tasks.
How does it work?
The basic principle of the Gantt Chart is to show time in a number of columns and to draw bars
across those columns in order to show the usage of time. Each bar represents a task being
carried out by one or more people. The bars can be summed downwards into simple histograms
to show whether individuals are double-booked or have spare time on their hands.
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Additional symbols and colours may be added to the chart to show events and features such as
milestones (zero-length tasks), critical paths (which, if extended, will slip the completion date
of the project) and float (where tasks can be slipped without jeopardizing the completion date).
Characteristics of Gantt/Bar Chart
Popular tool for project scheduling
Graph with bar representing time for each task
Provides visual display of project schedule
Doesn’t show priorities
Gantt charts may be simple versions created on graph paper or more complex automated
versions created using project management applications such as Microsoft Project or
Excel.
How do you do it?
1. Break down the task into units that can be clearly allocated and tracked. In a typical project
this might be tasks of one week or less, allocated to one person each (although this can vary
widely with the type of project).
2. Identify skills and resources required by each task and allocate the task to a person or group,
along with appropriate resources. Be careful when allocating scarce resources, such as subject
specialists or expensive equipment; a person with less skill who can perform the task, albeit
over a longer period, can free up the expert for working on more critical activities.
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3. Revise the time estimate for each task in the light of the skills of the people on the task.
Beware of optimistic estimation. It can be helpful later if a 'safety factor' of anything from 10%
to 100% is added to allow for slippages. It is usually more acceptable to complete a project
ahead of schedule than have to continually move out the completion date.
4. Identify dependencies between tasks and other prioritisation that will allow you to put the
tasks into the correct order. For example, it is better to do high-risk tasks as early as possible,
to give you time to react to unexpected difficulties.
5. Draw up a blank Gantt Chart with enough lines on for all identified tasks and with columns
spanning the range of times and/or dates to be displayed. Make the period between each
column in the same range as the average task length, for example if most tasks are from one to
five weeks, make each column one week (provided there is space on the paper).
6. Write the tasks into the chart and add bars to indicate the start time and duration of each
tasks. This is where the real skill in scheduling is found as you need to position tasks carefully
to ensure that dependencies (where one task must follow another task) are preserved and that
people and other resources are optimally used.
Drawing a Bar Chart and Network
For the following problem, we can draw a Bar chart and Network
Activity
Designation
A
B
C
D
E
F
G
H
(1-2)
(2-3)
(2-4)
(2-5)
(3-5)
(5-6)
(4-6)
(6-7)
Immediate
Predecessor
None
A
A
A
B
D,E
C
F,G
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Duration
2
5
7
3
1
6
3
3
Bar Chart for the above Example
Activity/
Duration(Weeks)
A
5
10
15
20
B
C
D
E
F
G
H
17Weaks
Total duration of the project is 17 weeks as seen from the bar chart
Network technique used in project management
Network technique involves breaking down the project into work elements, which can be
quantified in term of time and other resources required to perform these. Once the entire project
has been broken down into such work elements or tasks/ activities, adequate enough to establish
their logical sequence and their inter dependencies, we try to develop, what a network diagram A
network for a hypothetical small project is shown below. 1 to 7 are nodes or events, as they are
called, and arrow or arcs, connecting the nodes, viz. A to H, are the activities. T he diagrams
shows the logical sequence in which the activities are to be performed, and their interdependencies. Whereas activities occupy time, nodes/ events are points in time, which mark the
start/ finish of the activities. Activity time in weeks is shown below each arrow in parentheses
( ):
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Fig: Project Network for the above hypothetical project
3
E
B
(5)
1
A
(2)
2
(1)
D
(3)
C
(7)
5
F
(6)
G
(3)
6
H
(3)
7
4
We may note from the network (Fig ), the event (1) marks the start of the project and ‘A’ is the
first activity to be performed, since there is no activity terminating at (1), i.e., there is no
predecessor to activity ‘A’ has been completed. Event (2), thus, marks the end of activity ‘A’
and start of activities ‘B’, ‘C’ & ‘D’. Similarly, activity ‘F’ cannot start unless activities ‘D’ &
‘E’ have been completed, which is marked by event (5), and so on. Event (7) marks the end of
the project, ‘H’ being the last activity to be performed, since no activity emanates from (7), i.e.,
there is no successor to activity ‘H’.
The network is based on the following table of activities and their logical sequence, as
determined by immediate predecessors of the respective activities indicated in Table 1:
ACTIVITY ON ARC/NODE
The above-mentioned way of representing activities in a network as shown in Fig, is called
activity on arrow/arc
There is an alternative way of drawing a network, in which we have activities on node, instead
of on arrow/arc in the alternative representation, the network look as show below in Fig. The
arrow connection the various activities, A to H, depict their interrelationship, or precedence
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Fig: Network of Activities of the Project
Showing Activities on Node
B
E
H
F
C
A
C
C
The former way of representation of network is also referred to as Arrow Diagram and the
latter, Precedence Diagram
In order to illustrate the bar chart further when each of the work packages have their tasks, such
an example is worked out below.
Bar chart - Example
Week 1
Week 2
Week 3
Work Packages
Tasks
Work Package 1
Task 1
Task 2
Task 3
Task 4
Work Package 2
Task 1
Task 2
Task 3
Work Package 3
Task 1
Task 2
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Week 4
Week 5
Week 6
It is necessary that the officers who are deployed in project Management need to undergo
training and equip themselves with the skills to apply the tools such as Bar/Gant charts, CPM
and PERT.
CPM - Critical Path Method
DuPont developed a Critical Path Method (CPM) designed to address the challenge of shutting
down chemical plants for maintenance and then restarting the plants once the maintenance had
been completed. Complex project, like the above example, require a series of activities, some of
which must be performed sequentially and others that can be performed in parallel with other
activities. This collection of series and parallel tasks can be modeled as a network. CPM models
the activities and events of a project as a network. Activities are shown as nodes on the network
and events that signify the beginning or ending of activities are shown as arcs or lines between
the nodes.
As a Planning and Scheduling Tool:
It is a formal, graphic means of determining the relationship between the activities
(tasks) in a project.
It enables systematic isolation of activities comprising the critical elements that set
the duration of a project.
It helps the project manager analyze a project before, during, and after operations.
The greatest asset of CPM is its portrayal of critical activities, giving the project
manager forewarning of where he or she might expect schedule problems.
The core of CPM is a network diagram that represents the manager's best effort at
efficient planning and scheduling of project activities.
The network diagram consists of arrows (activities) and circles (events). Activities
represent work and consume resources and time; events do not, rather they mark
points in time when activities begin or finish. The length of an arrow has no
relevance.
Eight Steps to Using CPM to Manage a Project
Identify the activities (tasks) in the project and their durations.
Determine for each activity the logic that governs when it can occur, i.e., what must
precede the activity, what can occur at the same time, and what must follow (precedence,
concurrence, succession).
Draw a network diagram that reflects the best progression of the project (i.e., order
activities in a logical sequence that minimizes project duration). For each activity, place
the name of the activity above the arrow and the duration of the activity below the arrow.
Determine the earliest event times (EETs) and latest event times (LETs) for each event in
the network diagram.
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Compute EETs
– The EET for Event 1 is 0 (representing the end of day 0 or the beginning of day 1).
– Trace each activity and add that activity's duration to the preceding EET. The sum will
be the EET for the next event, unless two or more activities enter that event. IF two or
more activities enter an event, the EET for that event will be the largest of the computed
EETs, SINCE activities leaving that event cannot begin until all activities entering the
event are complete. Place the EET in a box symbol adjacent to the event symbol.
Continue the procedure from left to right until reaching the end of the diagram.
The EET for the last event is the earliest possible time the entire project can be
completed, given the network as drawn and the activity durations assigned.
Determine and highlight the critical path (those critical activities that define the duration
of the project). Activities are critical if:
– The EET and LET at the tail of the activity are equal.
– The EET and LET at the head of the activity are equal.
– The difference between the EET (or LET) at the head and the EET (or LET) at the
tail equals the activity duration.
–
There will be at least one critical path extending from the beginning to the end of the project.
Tabulate activity times (early start, early finish, late start, late finish, total float, and free float)
that can help you schedule resources and identify schedule flexibility.
Early Start (ES) = The EET (entered in the box symbol) at the tail of the activity
arrow
Early Finish (EF) = ES + Activity Duration
Late Start (LS) = LF - Activity Duration
Late Finish (LF) = The LET (entered in the triangle symbol) at the head of the
activity arrow
Total Float (TF) = LS - ES = LF – EF
Free Float (FF) = EET (at the head) – EF
Interfering float (that which delays a subsequent activity, but not the total project) equals
TF - FF; for a given activity, it is also equal to the difference between the LET and EET
at the head of that activity's arrow. Schedule activities and allocate resources to maximize
efficiencies and minimize project time. During the project, measure progress; taking
action where necessary and modifying the network diagram as needed.
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For example, the Early start, early finish, late start and late finish times and the slack or the float
or the free time available for the activity to commence are worked out for the above project as
given in the table below.
Duration in weeks
Activity
A*
B*
C
D
E*
F*
G
H*
Duration
2
5
7
3
1
6
3
3
ES
0
2
2
2
7
8
9
14
EF
2
7
9
5
8
14
12
17
LS
0
2
4
5
7
8
11
14
LF
2
7
11
8
8
14
14
17
S
0
0
2
3
0
0
2
0
CPM Diagram
Activity
Event
1
Excavation
2
Event
2
Foundation
4
Event
3
Duration (Weeks)
The event circles bounding an activity are numbered, the number of the tail event is that
activity's 1 designation; the number of the head event is that activity's "2" designation. By
convention, 2 are numerically higher than 1, portraying left to right movement through the
network diagram. The 2 designation of a preceding activity is the 1 designation of the
succeeding activity.
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Steps in CPM Project Planning
1. Specify the individual activities.
2. Determine the sequence of those activities.
3. Draw a network diagram.
4. Estimate the completion time for each activity.
5. Identify the critical path (longest path through the network)
6. Update the CPM diagram as the project progresses.
1. Specify the individual activities
All the activities in the project are listed. This list can be used as the basis for adding
sequence and duration information in later steps.
2. Determine the sequence of the activities
Some activities are dependent on the completion of other activities. A list of the immediate
predecessors of each activity is useful for constructing the CPM network diagram.
3. Draw the Network Diagram
Once the activities and their sequences have been defined, the CPM diagram can be drawn.
CPM originally was developed as an activity on node network.
4. Estimate activity completion time
The time required to complete each activity can be estimated using past experience. CPM
does not take into account variation in the completion time.
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5. Identify the Critical Path
The critical path is the longest-duration path through the network. The significance of the critical
path is that the activities that lie on it cannot be delayed without delaying the project. Because of
its impact on the entire project, critical path analysis is an important aspect of project planning.
The critical path can be identified by determining the following four parameters for each activity:
• ES - earliest start time: the earliest time at which the activity can start given that its precedent
activities must be completed first.
• EF - earliest finish time, equal to the earliest start time for the activity plus the time required to
complete the activity.
• LF - latest finish time: the latest time at which the activity can be completed without delaying
the project.
• LS - latest start time, equal to the latest finish time minus the time required to complete the
activity.
The slack time for an activity is the time between its earliest and latest start time, or between its
arliest and latest finish time. Slack is the amount of time that an activity can be delayed past its
earliest start or earliest finish without delaying the project.
The critical path is the path through the project network in which none of the activities have
slack, that is, the path for which ES=LS and EF=LF for all activities in the path. A delay in the
critical path delays the project. Similarly, to accelerate the project it is necessary to reduce the
total time required for the activities in the critical path.
6. Update CPM diagram
As the project progresses, the actual task completion times will be known and the network
diagram can be updated to include this information. A new critical path may emerge, and
structural changes may be made in the network if project requirements change.
CPM Benefits
• Provides a graphical view of the project.
• Predicts the time required to complete the project.
• Shows which activities are critical to maintaining the schedule and which are not.
Concept of critical path Method (CPM), Tradeoff between Cost & Time,
Activity Crashing
In this method of network analysis, it is assumed that activity durations are deterministic, i.e.
known with certainty. Such projects are of repetitive and non- complex in nature, e.g.
stereotyped construction project. This can be successfully applied for projects employing fairly
stable technology, with well-established database, which are relatively time, though
deterministic, is not fixed, and varies according to changes in resources assignment to the
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respective activity. By analyzing the network and utilizing the quantified time-cost relationship,
we try to determine the project schedule, which minimizes or rather optimizes the total cost. We
know that any reduction in the duration of the critical activities (called crashing of the activities),
suitably, would result in reduction of the project duration. Main focus in CPM is tradeoff
between cost and time of project completion. Such activity crashing would , in most cases,
involve deployment of increased resources, e.g. manpower, construction plant “& equipment,
materials, etc., with attendant increase in the direct cost of the activity on the other hand,
reduction on project duration would simultaneously result in decrease in indirect cost of the
project (overhead items, viz. project establishment cost and other preoperative expenses which
have direct relationship with the project duration) Trade off tries to minimize total cost or project
duration or to adjust the duration to match the project cost with budget/ funds and/ or other
resource constraints.
CPM Limitations
While CPM is easy to understand and use, it does not consider the time variations that can have a
great impact on the completion time of a complex project. CPM was developed for complex but
fairly routine projects with minimum uncertainty in the project completion times. For less routine
projects there is more uncertainty in the completion times, and this uncertainty limits its
usefulness.
Program Evaluation and Review Technique (PERT)
The Program Evaluation and Review Technique (PERT) is a network model that allows for
randomness in activity completion times. PERT was developed in the late 1950's for the Navy's
Polaris project having thousands of contractors. It has the potential to reduce both the time and
cost required to complete a project.
The Network Diagram
In a project, an activity is a task that must be performed and an event is a milestone marking the
completion of one or more activities. Before an activity can begin, all of its predecessor activities
must be completed. Project network models represent activities and milestones by
arcs and nodes. PERT is typically represented as an activity on arc network, in which the
activities are presented on the lines and milestones on the nodes.
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PERT Chart
The milestones generally are numbered so that the ending node of an activity has a higher umber
than the beginning node. Incrementing the numbers by 10 allows for new ones to be inserted
without modifying the numbering of the entire diagram. The activities in the above diagram are
labeled with letters along with the expected time required to complete the activity.
Steps in the PERT Planning Process
PERT planning involves the following steps:
1. Identify the specific activities and milestones.
2. Determine the proper sequence of the activities.
3. Construct a network diagram.
4. Estimate the time required for each activity.
5. Determine the critical path..
6. Update the PERT chart as the project progresses.
progresses
1. Identify activities and milestones
The activities are the tasks required to complete the project. The milestones are the events
marking the beginning and end of one or more activities.
2. Determine activity sequence
This step may be combined with the activity identification step since the activity sequence is
known for some tasks. Other tasks may require more analysis to determine the exact order in
which they must be performed.
3. Construct the Network Diagram
Using the activity sequence information, a network diagram can be drawn showing the
sequence of the serial and parallel activities.
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4. Estimate activity times
Weeks are a commonly used unit of time for activity completion, but any consistent unit of
time can be used.
A distinguishing feature of PERT is its ability to deal with uncertainty in activity completion
times. For each activity, the model usually includes three time estimates:
• Optimistic time (OT) - generally the shortest time in which the activity can be
completed. (This is what an inexperienced manager believes!)
• Most likely time (MT) - the completion time having the highest probability. This is
different from expected time. Seasoned managers have an amazing way of estimating
very close to actual data from prior estimation errors.
• Pessimistic time (PT) - the longest time that an activity might require.
The expected time for each activity can be approximated using the following weighted
average:
Expected time = (OT + 4 x MT+ PT) / 6
This expected time might be displayed on the network diagram.
Variance for each activity is given by:
[(PT - OT) / 6]2
5. Determine the Critical Path
The critical path is determined by adding the times for the activities in each sequence and
determining the longest path in the project. The critical path determines the total time required
for the project. If activities outside the critical path speed up or slow down (within limits), the
total project time does not change. The amount of time that a non-critical path activity can be
delayed without delaying the project is referred to as slack time.
If the critical path is not immediately obvious, it may be helpful to determine the following
four quantities for each activity:
• ES - Earliest Start time
• EF - Earliest Finish time
• LS - Latest Start time
• LF - Latest Finish time
These times are calculated using the expected time for the relevant activities. The ES and EF of
each activity are determined by working forward through the network and determining the
earliest time at which an activity can start and finish considering its predecessor activities. The
latest start and finish times are the latest times that an activity can start and finish without
delaying the project. LS and LF are found by working backward through the network. The
difference in the latest and earliest finish of each activity is that activity's slack. The critical path
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then is the path through the network in which none of the activities have slack. The variance in
the project completion time can be calculated by summing the variances in the completion times
of the activities in the critical path. Given this variance, one can calculate the probability that the
project will be completed by a certain date. Since the critical path determines the completion date
of the project, the project can be accelerated by adding the resources required to decrease the
time for the activities in the critical path. Such a shortening of the project sometimes is referred
to as project crashing.
6. Update as project progresses
Make adjustments in the PERT chart as the project progresses. As the project unfolds, the
estimated times can be replaced with actual times. In cases where there are delays, additional
resources may be needed to stay on schedule and the PERT chart may be modified to reflect
the new situation.
Benefits of PERT
PERT is useful because it provides the following information:
•
•
•
•
•
Expected project completion time.
Probability of completion before a specified date.
The critical path activities that directly impact the completion time.
The activities that have slack time and that can lend resources to critical path activities.
Activities start and end dates.
Limitations of PERT
The following are some of PERT's limitations:
•
The activity time estimates are somewhat subjective and depend on judgment. In cases
where there is little experience in performing an activity, the numbers may be only a
guess. In other cases, if the person or group performing the activity estimates the time
there may be bias in the estimate.
•
The underestimation of the project completion time due to alternate paths becoming
critical is perhaps the most serious.
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Meanings of Network Terms
Activity
Critical Activity
An activity always consumes time and resources
Work
8 days
The word critical is applied to any activity or event that must be achieved
by a certain time and has no latitude whatsoever and failure to achieve the
specified time will result in the project end date slipping
Critical Path
Longest path through the project network and determines the earliest date
on which work can be completed
Dummy
Denotes nothing but dependency and carries no time and represented by
……………….. lines
Event
Beginning and ending points Denoted by
Event i
event j
Mile stone
A point in a project of special significance ie completion of a major phase
of work
Network
Graphical representation of a project plan showing the interrelationship of
activities
Burst event
Merge event
Network
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Network Rules
Rule.1
Rule.2
Before an activity may begin, all activities preceding it must be completed
Arrows imply logical precedence only, neither the length of the arrow nor its compass”
direction on drawing have any significance
x
6
y
wrong logic
7
Loop to e avoided
x
6
7
25
Install Machine
Inspect machine
Install
Hireoperator
Correct logic
Train operator
Inspect
Hireoperator Train operator
Basic scheduling computations
(1) Initial event is assuming to occur at time zero
(2) E1 =0
(3) EF time of an activity = early start of act + activity duration
Forward pass computations
Back word pass computations
183
y
Draw Backs of Project Implementation in an Urban Infrastructure Project
Project Implementation
Supervision
of Civil
Works
Suffered Lack of
Adequate
Technical
Staff
Delay in Land
Acquisition
Poor Co-ordination
among Line
Departments
•
•
Only two JEs
were working
Municipality
has no control
over other
departmental
projects
Integration
could not be
achieved
184
Finances
•
•
•
•
Interruption in
Flow of Funds
to the Project
Revolving Fund
was not created
Income
generated was
used for other
infrastructure
Separate
Account was
not opened
Corrections Required
Project Implementation
Inadequate
Technical and
Accounts Staff
Adequate
Technical and
Accounts Staff
Land Acquisition
•
•
•
•
Use tools
Gantt chart,
CPM/PERT
Networks
Land Pooling.
Land Bank by
ULB
Participation
of Land
Owners in
the Project
Guided Land
Development
Poor Coordination
Finances
Government to
evolve guidelines
for coordinated
project
implementation
State
and
Central
Share to
be
released
Single Window
clearance at
district and
state level
Create
Separate
Account
for
schemeo
ject
Budgets of each
to be prepared
keeping the
development
works of other
departments
Create
Revolving
Fund
185
State
Guarantee to
ULB for
Institutional
Loan
QUIZ
Chapter 6
1. Project schedule involves
a. Identifying activities
b. Sequencing
c. Determining duration & resources
d. All of above
2. First step towards a work plan is WBS
a. True
b. False
3. Purpose of WBS is
a. Dividing the project into work packages
b. Assign responsibility to each tasks
c. a & b
d. None of the above
4. Which tool and technique is used to Create WBS and Define activities?
a. Nominal group technique
b. Human resource assignment
c. Brainstorming
d. Decomposition
5. You have been assigned as a project manager to a software project. While you and
your team are working on a WBS (Work breakdown structure), estimations for
activity durations based on the activity list vary significantly. Which additional
documents may help you clarify this situation?
a. Milestone list and scope baseline.
b. Project schedule network diagrams and human resource plan
c. Activity cost estimates and scope baseline.
d. Activity attributes and project scope statement.
6. Gantt chart is invented by Hennery Gantt in 1917
a. True
b. False
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7. Which of the following is especially useful for monitoring project progress against
plan?
a.
Gantt charts.
b. Capacity loading graphs.
c.
Network diagrams.
d. Flow diagrams.
e.
All of the above.
8. Bar chart does not show priorities
a. True
b. False
9. Which of the following is not a reason to reduce project completion time?
a. Avoid penalties for late completion.
b. Reduce new product development time to market.
c. Gain incentives for early completion
d. Release resources for other projects
e. Eliminate project critical path
10. For the following problem, What is the total duration
Activity Designation
A
B
C
D
E
a.
b.
c.
d.
(1-2)
(2-3)
(2-4)
(2-5)
(3-5)
Immediate
Predecessor
None
A
A
A
B
Duration
2
5
7
3
1
19
30
17
9
11. In the network diagram arrows & circles indicate activities & events respectively
a. True
b. False
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12. In critical path, early event time & late event time at the tail of the activity are
equal
a. True
b. False
13. Total float in an activity is calculated as
a. Late finish –Early finish
b. Late finish –Early start
c. A &B
d. None of the above
14. In project management PERT refers to
(a) Project Energy Rating Time
(b) Project Energy Rating Terms
(c) Petroleum Energy Revolutionary Technology
(d) Program Evaluation and Review Technique.
15. Significance of critical path
a. Activities on it cannot be delayed without delaying the project
b. Longest duration path through the network
c. Activities on it have no slack/freetime
d. None of the above
16. Which of the following are benefits of the network analysis approach?
a. Allows progress to be monitored against plan
b. Derive error free forecasts.
c. Avoid need to use structured approach
d. Eliminate need for management judgment
e. None of the above
17. You have used estimates made by your team members and applied the Critical
path method to compute a Network logic diagram for your project. Then you
found out that it cannot be sufficiently optimized for scarce resources and fast
progress towards a given deadline. What should you do next?
a. Apply resource leveling heuristics to uncritical activities only.
b. Reduce estimates on duration and work efforts by an adequate percentage.
c. Apply Three-point estimation and Critical chain project management.
d. Remove physical constraints and replace hard logic with soft logic.
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18. A Gantt chart indicates: (Note: more than one answer is correct.)
a. The sequence of activities.
b. Elapsed time of different activities on project
c. Activities occurring in parallel.
d. Overall elapsed time on project
e. None of the above.
19. A project can be considered to have failed if it:
(Note: more than one answer is correct.)
a. Does not meet the business requirements
b. Does not meet the users' requirements
c. Was significantly over budget.
d. Overran significantly on estimated delivery date
e. None of the above
20. SWOT (Strengths, weaknesses, opportunities and threats) analysis can be used in
project management.
a. True
b. False
21. A PERT chart is a project management tool which illustrates how tasks depend on
each other.
a. True
b. False
22. With your team you are using judgment from subject matter experts to identify
and analyze project risks. There is a small number of experts available, but some
of them have long been in a teacher-student or manager-assistant relationship.
Which of the following techniques can ensure best that there is no dominating
opinion during an expert review?
a.
Peer review
b.
SWOT analysis
c.
Delphi technique
d.
Monetary value calculation
189
TEMPLATE
Case Example
Replacing an existing boiler with Solar Water Heating System
Activity Code
A
B
C
D
E
F
G
H
I
J
Activity
Prepare technical specifications
Tender Processing
Release of work orders
Supply of Solar equipment
Supply of Auxiliaries
Supply of pipes & pipe fittings
Civil Work
Installation of Auxiliary equipment &
piping
Installation of Solar water Heater
Testing Commissioning
Duration in days
10
25
3
60
20
10
15
5
Depends on
A
B
C
C
C
C
E, F & G
10
2
D&H
I
Gantt chart
The Figure shows a Gantt chart for a simple energy management project, i.e. Replacing existing
boiler with solar water heater
As already mentioned, Gantt chart is the simplest and quickest method for formal planning.
Gantt charts can be very useful in planning projects with a limited number of tasks and with few
inter-relationships. This chart typically depicts activities as horizontal lines whose length
depends on the time needed to complete the activities. These lines can be progressively
overprinted to show how much of activity has been completed.
Drawing a Gantt chart requires information on:
•
•
•
The logic of the tasks.
The duration of the asks
The resources available to complete the tasks.
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Task Duration
(days)
A
10
B
25
C
3
D
60
E
20
F
10
G
15
H
5
I
10
J
2
Prepare technical specifications
Tender Processing
Release of work orders
Supply of solar water heaters
Supply of equipment
Supply of pipes & pipe fittings
Civil Work
Installation of equipment & piping
Installation of solar heater
Testing and Commissioning
Simple Gantt Chart for Boiler Replacement
Also draw CPM Network.
191