Project Management in Practice Second Edition Mantel, Meredith, Shafer, and Sutton Prepared by Scott M. Shafer Wake Forest University John Wiley and Sons, 5-1
Chapter 5 Scheduling the Project 5-2
PERT AND CPM NETWORKS 5-3
Tarihçe 1950 lerin sonlarında Program Evaluation and dreview Technique (PERT) Program değerlendirme ve gözden geçirme tekniği U.S. Navy, Booz-Allen Hamilton, and Lockeheed Aircraft Probabilistic faaliyet süreleri Critical Path Method (CPM) Kritik yol yöntemi Dupont De Nemours Deterministic faaliyet süreleri 5-4
PERT/CPM terminolojisi i Activity Faaliyet-İşlem Görev veya görevler seti Kaynak kullanır Event- Olay- Düğüm Bir yada daha fazla faaliyetin tamamlanması durumu Kaynak ya da zaman kullanmaz Öncel(öncül) faaliyetler tamamlanmalı 5-5
PERT/CPM terminolojisi Milestones- kilometre taşları events that mark significant ifi progress Network Ağ-Serimğ diagram of nodes and arcs used to illustrate technological relationships Path -Yol series of connected activities between two events 5-6
PERT/CPM Critical Path Kritik Yol set of activities i i on a path that if delayed d will delay completion of project Critical Time Kritik süre- Proje tamamlanma süresi time required to complete all activities on the critical path 5-7
Network- Ağı oluşturma AOA (Activity 0n Arc) Network (faaliyetlerin oklarla gösterimi AON(Activity on Node) Network (faaliyetlerin düğümlerle gösterimi) 5-8
Table 5-1 A Sample Set of Project Activities and Precedences Task Predecessor a -- b -- c d e f g a b b c, d e 5-9
Figure 5-1 Stage 1 of a Sample AON Network 5-10
Figure 5-2 Stage 2 of a Sample AON Network 5-11
Figure 5-3 A Completed Sample AON Network 5-12
Figure 5-4 Stage 1 of a Sample AOA Network 5-13
Figure 5-55 Stage 2 of a Sample AOA Network 5-14
Figure 5-6a A Completed Sample AOA Network 5-15
Figure 5-6b A Completed Sample AOA Network Showing the Use of a Dummy Task 5-16
Table 5-2 A Sample Problem for Finding the Critical Path and Critical Time Activity Predecessor Duration a -- 5 days b -- 4 c a 3 d a 4 e a 6 f b, c 4 g d 5 h d, e 6 i f 6 j g, h 4 5-17
Figure 5-7 Stage 1 of a Sample Network 5-18
Figure 5-8AC Complete Network 5-19
Figure 5-9 Information Contents in an AON Node 5-20
Figure 5-10 The Critical Path and Time for Sample Project 5-21
Faaliyetlerin Boşluk Sürelerini Hesaplama Slack or Float LST - EST = LFT - EFT = Slack (boşluk) 5-22
Figure 5-11 An MSP Version of PERT/CPM Network 5-23
Figure 5-12 A Modified Version of MSP Network 5-24
PROJECT UNCERTAINTY AND RISK MANAGEMENT 5-25
Calculating Probabilistic Activity Times Three Time Estimates Pessimistic i i (kötümser) (b) most likely(en olası)(m) Optimistic(iyimser) (a) 5-26
Figure 5-13 The Statistical Distribution of all Possible Times for an Activity (beta dağılımı) 5-27
Activity Expected Time and Variance T E = ( a + 4m 6 + b) σ = ( b 6 a) Var = σ 2 ( b a ) = 6 2 5-28
95 Percent Level Task will be a or lower 5 percent of the time Task will be b or greater 5 percent of the time σ = (b b a) ) 3.33 5-29
90 Percent Level Task will be a or lower 10 percent of the time Task will be b or greater 10 percent of the time σ = (b b a) ) 2.6 5-30
95 Percent Level (Alternative Interpretation) Task will be between a and b 95 percent of the time σ = ( b a) 3.92 5-31
90 Percent Level (Alternative Interpretation) Task will be between a and b 90 percent of the time σ = ( b a) 3.29 5-32
Figure 5-14 An AON Network 5-33
Figure 5-15 An MSP Version of a Sample Problem Network 5-34
Figure 5-16 A Pert/CPM Network for the Day Care Project 5-35
Figure 5-17 An MSP Calendar for the Day Care Project, 4/16/00 to 5/27/00 5-36
The Probability of Completing the Project on Time Z (D ) = D μ σ 2 μ =NORMDIST(D,μ,σμ σ μ,true) 5-37
Figure 5-18 The Statistical Distribution of Completion Times of the Path a-b-d-g-h 5-38
Sl Selecting Risk ikand Finding idi D D = μ + 2 σ = μ Z σ μ NORMINV(probability,μ,σ μ,true) 5-39
SIMULATION 5-40
Traditional Statistics Versus Simulation Similarities must enumerate alternate paths Differences simulation does not require assumption of path independence 5-41
THE GANNT CHART 5-42
Figure 5-23 A Gantt Chart of a Sample Project 5-43
Figure 5-24 A Gantt Chart of Sample Project Showing Critical Path, Path Connections, Slack, EST, LST, EFT, and LFT 5-44
Figure 5-25 A Gantt Chart of a Day Care Project Showing Expected Durations, Critical Path, Milestone, and Resource Requirements 5-45
Figure 5-26 A Progress Report on a Day Care Project Showing Actual Progress Versus Baseline 5-46
EXTENSIONS TO PERT/CPM 5-47
Precedence Diagramming i Finish-to-start linkage Start-to-start linkage Finish-to-finish linkage Start-to-finish linkage 5-48
Figure 5-27 Precedence Diagramming Conventions 5-49
Oh Other Methods Graphical Evaluation and Review Technique e (GERT) combines flowgraphs, probabilistic networks, and decision trees allows loops back to earlier events and probabilistic branching 5-50
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