MEE 3164 Lecture 8 TMEE 3164 Lecture 8 T..pptx

MEE 3164 Lecture 8 T.pptx

1. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 1 Engineering Operation Management MEE 3166 Instructor : Dr Gaudence Lecture :8 PROJECT MANAGEMENT

2. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 2 Project Management Project : is an interrelated set of activities that has a definite starting and ending points, resulting in a unique product or service. That means projects are not repetitive. Interrelated activities are arranged in a logical sequence, which is referred to as a precedence relationship . Few examples of projects are : Constructing a bridge, dam, highway or building. Producing an airplane, missile or large machine. Introducing a new product. Installing a large computer system. Redesigning the layout of plant or office. Construction of a ship. Fabrication of a steam boiler . Project management: is a scientific way of planning, implementing, monitoring & controlling the various aspects of a project such as time, money , materials, manpower & other resources to achieve specific objectives.

3. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 3 Network Planning Methods Network: is a graphical representation of the project activities arranged in a logical sequence and depicting all the interrelationships among them . Methods used for network planning are: CPM PERT Managing a project with network planning methods involves four steps: Describing the Project. Diagramming the Network. Estimating time of completion. Monitoring Project Progress.

4. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 4 Network Diagram Concepts Activity: An activity is a task or any item of work to be done in a project. It is a time consuming process. It is represented by an arrow in the network diagram (AOA system ). Precedence relationship (predecessor: the activity which should be completed before starting another is called a predecessor) Successor: an activity that can only begin after the completion of its preceding activity Event: the beginning and ending points of activities are known as events

5. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 5 Guidelines for network diagram Before an activity can begin, its preceding activities must be completed. Arrows indicate logical precedence. Flow of the diagram is from left to right. Arrows should not intersect. Dangling should be avoided . Dangling: To disconnect an activity before the completion of all activities in a network diagram

6. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 6 Approaches for Network Diagram ACTIVITY ON ARC(AOA ): Uses arcs to represent activities and nodes to represent events. It is Event Oriented . Activities which don’t have predecessors should start at same starting node

7. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 7 DUMMY ACTIVITY AOA approach requires the addition of a Dummy Activity to clarify the precedence relationships between the two activities. It is a zero time activity and consumes no resources. Dummy Activity is used in two situations : When two or more activities start and end at the same nodes

8. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 8 DUMMY ACTIVITY 2. When two or more activities share the same precedence activity but not all the precedences are shared .

9. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 9 Approaches for Network Diagram ACTIVITY ON NODE(AON ): Uses nodes to represent activities and arcs indicate precedence relationships between them. It is Activity Oriented..

10. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 10 Estimating time of completion Planning schedule of project Time estimates include: Total time for completion. 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: equals to the earliest start time for the activity plus the time required to complete the activity. LF- Latest finish time: the latest time in 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. FORWARD PASS: The early start and early finish times are calculated by moving forward through the network and considering the predecessor activities. The maximum number of time is taken

11. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 11 Estimating time of completion BACKWARD PASS: The latest start and finish times are calculated by moving backward through the network. Considers minimum number of time 6) SLACK TIME: Slack time for an activity is the difference between its earliest and latest start time or between the earliest and latest finish time. Critical path is the path of activities having zero Slack time.

12. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 12 How to draw an AON Precedence Diagramming Method (Example 1)

13. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 13 Given the table of dependencies Construct a PDM (Example 2)

14. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 14 Determine the Early Start (ES) and Early Finish (EF) of activities in a PDM

15. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 15 Earliest start & earliest finish time This will help us in identifying the longest path through the network, i.e., the critical path. Starting at the network’s origin (node 1) and using a starting time of 0, we compute an earliest start (ES) and earliest finish (EF) time for each activity in the network . The expression EF = ES + t (duration) can be used to find the earliest finish time for a given activity. For example, for activity A, ES = 0 and t = 5; thus the earliest finish time for activity A is EF = 0 + 5 = 5 Each time multiple predecessor activities lead into the same activity, we pick the largest EF as ES for this next activity.

16. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 16 Determine Late Start (LS) and Late Finish (LF) of activities in PDM (AON) diagram

17. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 17 Latest start & latest finish time We also need LS & LF to find the critical path. To find them we perform a backward pass calculation. Starting at the completion point and using a latest finish time (LF) of 19 for activity F, we trace back through the network computing a latest start (LS) and latest finish time for each activity All we do, we come to the very end of the project and we take Earliest Finish and bring it down to the late finish Next we move backward, by substracting the activity duration from its LF number. Contrary to the forward pass ( for ES & EF) where we pick the larger value in the backward pass here we pick the smallest LS as the LF of the predecessor. The expression LS = LF – t can be used to calculate latest start time for each activity with t standing for duration. For example, for activity F, LF = 19 and t = 4, thus the latest start time for activity F is LS = 19 – 4 = 15

18. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 18 CRITICAL PATH DEFINITION : The Critical Path is the sequence of activities in a project that determines the longest duration for the project to be completed. Activities on the Critical Path are called “Critical Activities” Critical activities have no float or slack (explained later) Activities not on the Critical Path are called “Non Critical Activities To shorten the project duration, a scheduler must modify the critical path activities or dependencies

19. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 19 Critical Path Method Calculate Early Start & Early Finish dates (FORWARD PASS) Calculate Late Start & Late Finish dates (BACKWARD PASS) Calculate TOTAL FLOAT for each activity Identify activities with 0 (zero) TOTAL FLOAT (Activities having EF & LF being the same !) The critical path consists of activities that have zero slack/float.

20. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 20 Use forward and backward pass to determine project duration and critical path

21. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 21 Float (or Slack) Total Float – the total amount of time that a scheduled activity (or milestone) may be delayed or extended without delaying the project end date or violating a schedule constraint.

22. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 22 What is Total Float (Total Slack) and how to calculate it in a network diagram Critical path is the path of activities having zero Slack time.

23. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 23 Ex: Determine Total Float (Slack ) of activities in a network diagram Critical path is the path of activities having zero Slack time.

24. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 24 IMPORTANT QUESTIONS What is the total time to complete the project? 19 days if the individual activities are completed on schedule. What are the scheduled start and completion times for each activity? ES, EF, LS, LF are given for each activity. What activities are critical and must be completed as scheduled in order to keep the project on time? Critical path activities: A, B, D, G, and H. How long can non-critical activities be delayed before they cause a delay in the project’s completion time Slack time available for all activities are given.

25. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 25 PERT: TIME ESTIMATES PERT ( Programme Evaluation and Review Technique ) is similar to CPM, but the difference is in time estimates. CPM: Deterministic PERT : Probabilistic (have three time estimates) Optimistic time Most likely time Pessimistic time

26. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 26 PERT: TIME ESTIMATES Optimistic time (to) – It is the shortest time in which the activity can be completed. Most likely time (tm) – It is the probable time required to perform the activity. Pessimistic time ( tp ) – It is the longest estimated time required to perform an activity. Expected time:

27. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 27 STEPS IN PERT Identify the specific activities. Determine proper sequence of the activities. Construct the network diagram. Estimate the time required for each activity. Determine the critical path. Update the PERT chart.

28. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 28 Example 1 .

29. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 29 Example .

30. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 30 Example 2 A project consists of the following activities and time estimates. Construct the network. Determine the expected task time and the critical path.

31. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 31 Example 2 Solution: The network diagram is shown below:

32. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 32 Example 2 .

33. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 33 Advantages and Disadvantages PERT/CPM has the following advantages A PERT/CPM chart explicitly defines and makes visible dependencies (precedence relationships) between the elements, PERT/CPM facilitates identification of the critical path and makes this visible, PERT/CPM facilitates identification of early start, late start, and slack for each activity, PERT/CPM provides for potentially reduced project duration due to better understanding of dependencies leading to improved overlapping of activities and tasks where feasible.

34. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 34 Advantages and Disadvantages PERT/CPM has the following disadvantages: There can be potentially hundreds or thousands of activities and individual dependency relationships, The network charts tend to be large and unwieldy requiring several pages to print and requiring special size paper, The lack of a timeframe on most PERT/CPM charts makes it harder to show status although colours can help (e.g., specific colour for completed nodes ), When the PERT/CPM charts become unwieldy, they are no longer used to manage the project.

35. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 35 Advantages and Disadvantages PERT/CPM has the following disadvantages: There can be potentially hundreds or thousands of activities and individual dependency relationships, The network charts tend to be large and unwieldy requiring several pages to print and requiring special size paper, The lack of a timeframe on most PERT/CPM charts makes it harder to show status although colours can help (e.g., specific colour for completed nodes ), When the PERT/CPM charts become unwieldy, they are no longer used to manage the project.

36. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 36 Exercises 1.A project consists of five activities. Activities P and Q run simultaneously. The relationship among the various activities is as follows : Activity T is the last operation of the project and it is also immediate successor to R and S. Draw the network of the Project. 2 . A project consists of seven activities. Activities P, Q, R run simultaneously. The relationships among the various activities is as follows : Activity “V is the last operation of the project and it is also immediate successor to S, T and U. Draw the network of the project.

37. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 37 Exercises 3 . The activities along with the dependency relationship are given below. Draw the arrow diagram.

38. Operations Management - MEE 3164 UR - CST Semester I 2024/2025 38 Exercises 4. Draw the network for the following activities and find critical path and total duration of project: