1. Reducing Project Duration
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Reducing Project Duration

2. Why Reduce the Project Time?
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Time to Market
competition
technology
Unexpected delays
weather
equipment failure
design issues
Imposed deadlines
top management goals
Focus:
Reduce time at
Min Cost or Max profit
Reassignment of key resources
equipment
other priority project
people

3. Options Overtime Adding Resources easy if available use in moderation
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Overtime
easy
use in moderation
impact on morale
productivity
Core Project Team
allows for focus
shared goal
program manager control
Do it twice – Fast & Correctly
redefine task for interm solution
likely more costly, time & money
use only when agreed by client
Adding Resources
if available
issue of productivity
more coordination required
delay in training
Outsourcing
frees up internal resources
lose of control
may reduce costs
core competency issue

4. Options when resources are constrained
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Fast Tracking
review for parallel activities
reconsider precedents
Critical Chain
Individual buffers vs Aggregate buffers
Forward vs Backward scheduling
Worst Case vs Average time estimates
Reducing Project Scope
transfer some activities to client
Compromise Quality
establish what level of quality is required rather than is preferred.
Using the Critical Chain Method, projects can be completed more quickly and with greater scheduling reliability.
The difference between traditional and Critical Chain scheduling is in how uncertainty is managed. In traditional project scheduling, uncertainty is managed by padding task durations, starting work as early as possible, multi-tasking, and focusing on meeting commitment dates.
The following bullet points illustrate some of the problems associated with traditional project scheduling:
Padding task durations (providing worst-case estimates) is done to ensure a high probability of task completion. The knowledge that there is so much safety time built into tasks results in various time wasting practices, e.g., waiting until the last moment to complete a task. As a result, all the safety time can be wasted at the start of the task so that, if problems are encountered, the task over-runs.
Starting work as early as possible, even when not scheduled, is a response to worst-case estimates. When workers give worst-case estimates, they don’t expect to stay busy with just one task – so they multi-task, working on several tasks at once by switching between them. The result is that everything takes a long time to complete and very little completes early.
With the focus on meeting commitment dates (start and finish), output from a task completed early will rarely be accepted early by the next person needing this output. So, any effort spent in finishing early will be wasted. Early delivery of one task can’t be used to offset lateness on another. Lateness, however, is always passed on and the lost time can’t be made up without cutting the specifications or increasing resources allocated to subsequent tasks, if possible.
Given the these issues, it’s not surprising that the most projects are always late.
In Critical Chain scheduling, uncertainty is primarily managed by (a) using average task duration estimates; (b) scheduling backwards from the date a project is needed (to ensure work that needs to be done is done, and it is done only when needed); (c) placing aggregate buffers in the project plan to protect the entire project and the key tasks; and (d) using buffer management to control the plan. The key tasks are those on which the ultimate duration of the project depends, also known as the Critical Chain.

5. Project Costs to Consider
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Project Indirect Costs
overhead costs ( supervisor, admin, consultants, interest)
typically linear
cost increase as project time increases
Rate of change is constant
Project Direct Costs
labor, materials, equipment and sometimes subcontractors
mostly curvilinear
costs decrease as project time increases
longer time the resources can be spread out
short time requires more resources at premium costs
Source of Costs?
Objective is to find the Optimum Total Costs
Total Costs = Indirect costs + Direct Costs

6. Crashing A Project Characteristics Costs of crashing'
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Characteristics
Costs of crashing'
Shortening of completion time
Benefits of crashing
Effective reduction only when critical path is reduced
Steps
Identify regular time and costs
Identify crashing time & costs
Identify critical path(s)
Find the minimal crashing cost on the critical path
Subtract the associated time from the event on the critical path
Recalculate the cost and time to complete
Redefine critical paths
Continue until the all the available crashing time has been used
Select the min cost
Note: If there are more than one critical path then an equal amount of time must be removed from each critical path.

7. Practical Considerations
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Collecting Crash Times can be difficult
defining the cost and time an activity can be reduced by adding resources
can be subjective.
Relationship between Costs & Time may not be linear.
Some argue the relationship is curvilinear
Long projects may require NPV computations
Consider risks of crashing each activity, not all the same.
crashing an activity can add to potential for mistakes, while others not.
Impact of crashing on Morale & Motivation
forcing a crash of a project can foster resentment by WP owner.
overtime maybe a problem for those receiving and those not.

8. What if Cost is not the issue?
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Reduce Project Scope
Have Owner take more responsibility
Outsourcing part or all of the project
Brainstorm cost-saving options
Review Priority Matrix

9. PERT Example Enter tasks and relationships in a Gantt chart format
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Task Predecessor Optimistic time Pessimistic Time Most Likely time A B
C A,B
D C
E C
F E
G C
H D,F,G
I G,F
J H
K I,J
Enter tasks and relationships in a Gantt chart format
Enter times using PERT toolbar.
Determine Critical Path.
What is the range of completion times for the project?
Using MS Excel determine the probability of completing the project in 75 days?

10. Crashing Project Time
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Activity Normal Cost Max Crash Time Crash Cost/Day
A $ $ 500
B $ $1000
C $
D $ $3000
E $ $1000
F $ $1000
G $ $3000
H $ $2000
I $ $2000
J $ $1000
K $ $1000
What activities would you recommend “crashing” to reduce the time by 5 days?
If you could save $700 per day how far would you reduce the project?
What would be your cost savings?
Note: Use the expected times for Normal Project Time.