11-1 ELC 347 project management Week 12

11-2 Agenda Integrative Project –4 th part due –Outline of deliverables (posted in WebCT)Outline of deliverables (posted in WebCT) Quiz 2 Corrected –More effort wouldn’t hurt Today we will discuss Critical Chain Project Scheduling

11-3 Schedule for the final few Days Nov 28 –Assignment 5 due Nov 30 –IP part 5 due –Discussion on resource Leveling (Chap 12) Dec 7 –IP part 6 Due (will be corrected and returned within 24 hours) –Quiz 3 Assigned (Chap 10, 11, 12, & 13) –Discussion on Project Evaluation and Control (chap 13) Dec Midnight –Resubmission of IP part 1 – 5 deadline Dec 10 AM –IP project (complete) due –Resubmission of Part 6 –IP project Presentation Dec noon –Quiz 3 Due One less quiz and 2 less assignments then was identified in syllabus

11-4 Course Grading Rubric Exams 12% each)36% Assignments 7% each)35% IP Project19% Pre-professional Conduct10% Total100%

11-5 Critical Chain Project Scheduling Chapter 11 © 2007 Pearson Education

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11-7 BAE Systems

11-8 Theory of Constraints & Critical Chain Project Scheduling A constraint limits system output. The Goal – Goldratt TOC Methodology 1.Identify the constraint 2.Exploit the constraint 3.Subordinate the system 4.Elevate the constraint 5.Repeat the process

11-9 Dr J Edwards Deming

11-10 Variation Common Cause Inherent in the system Special Cause Due to a special circumstance Managers should Understand the difference between the two Not adjust the process if variation is common cause Not include special cause variation in risk simulation Not aggregate discrete project risks

11-11 CCPM and the Causes of Project Delay How safety is added to project activities 1.Individual activities overestimated 2.Project manager safety margin 3.Anticipating expected cuts from management time 25% 50% 80% 90% Gaussian Distribution

11-12 Wasting Extra Safety Margin 1.The Student Syndrome a.Immediate deadlines b.Padded estimates c.High demand 2.Failure to pass along positive variation a.Other tasks b.Overestimation penalty c.Perfectionism 3.Multitasking 4.Path Merging

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11-14 Critical Chain Solutions  Central Limit Theorem  Standard deviation of the sum is less than the sum of the standard deviations!  Aggregating risk leads to reduced risk  Activity durations estimated at 50% level  Buffer reapplied at project level –Goldratt rule of thumb (50%) –Newbold formula (2σ)  Feeder buffers for non-critical paths

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11-16 CCPM Changes  Due dates & milestones eliminated  Realistic estimates – 50% level not 90%  “No blame” culture  Subcontractor deliveries & work scheduled ES  Non critical activities scheduled LS  Factor the effects of resource contention  Critical chain usually not the critical path  Solve resource conflicts with minimal disruption

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11-20 Critical Chain Solutions Bob Feeder Buffer Project Buffer Bob Buffers protect constraints and prevent delays

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11-22 Critical Chain Project Portfolios Drum – system-wide constraint that sets the beat for the firm’s throughput Drum – person, department, policy, resource Capacity constraint buffer – safety margin between projects Drum buffer – extra safety before the constraint

11-23 Applying CCPM to Project Portfolios 1.Identify the drum 2.Exploit the drum a.Prepare a schedule for each project b.Determine priority for the drum c.Create the drum schedule 3.Subordinate the project schedules (next slide) 4.Elevate the capacity of the drum 5.Go back to step 2

11-24 Subordinating Project Schedules Schedule projects based on drum Designate critical chain Insert capacity constraint buffers Resolve any conflicts Insert drum buffers so the constraint is not starved

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11-26 CCPM Critiques  No milestones used  Not significantly different from PERT  Unproven at the portfolio level  Anecdotal support only  Incomplete solution  Overestimation of activity duration padding  Cultural changes unattainable

11-27 Problems on 373 Assignment 5 –Problems 1,2,3 4 & 5 on page 373 & 373 Pert to CCPM –Figure total Duration –Take 50% activity duration Figure new total duration –Project buffer = 50%(old –new) –If you have non critical path critical Change to Late start Feeder buffer is 50% of slack on non –critical path