PERT-CPM for project management .pptx

Critical Path Method, or CPM, is a project modeling technique that helps project managers plan, schedule, and execute their projects effectively. It pinpoints the crucial tasks — the ones that, if delayed, would push back the project's entire timeline.

1. PERT/CPM Durga Prasad Pahari DCMFH, MMC, IOM

2. CPM: Critical Path Method (Industrial Origin) PERT: Program Evaluation Review Technique (Military Origin) Tools of Project Management Helps in Planning, Monitoring, Controlling and Decision making

3. Introduction - CPM Complex projects require a series of activities Some must be performed sequentially Others can be performed in parallel This collection of series and parallel tasks can be modeled as a network. In 1957, the Critical Path Method (CPM) was developed as a network model for project management. (Chemical Plant Establishment)

4. CPM Contd... The Critical Path Method (CPM) is one of the techniques for doing project planning. CPM is a method that uses a fixed time estimate for each activity. CPM does not consider the time variations that can have a great impact on the completion time of a complex project .

5. CPM is for projects that are made up of a number of individual ‘activities ’. CPM can help us figure out - how long our complex project will take to complete - which activities are "critical," meaning that they have to be done on time or else the whole project will take longer CPM Contd ...

6. CPM Contd... CPM analysis starts after we figured out all the individual activities in our project. Tasks which fall on the critical path should receive special attention by both the project manager and the personnel assigned to them.

7. CPM Contd .. Notice that there are three paths through the network: Path  A-C    B-D  A-D Length 6 7 8

8. CPM Contd .. The critical activities are those which lie on a longest path through the network - here A and D are critical. A longest path through a network is called a critical path .  

9. PERT PERT is a method to analyze the tasks involved in completing a given project, especially the time needed to complete each task. Developed by Booz-Allen Hamilton (US Navy special project office) in 1958 as a method to plan and control the Polaris Missile program. Developed to simplify the planning and scheduling of large & complex project Event oriented techniques applicable to projects where time rather than cost is a major factor . The Program Evaluation and Review Technique (PERT) is a network model that allows for randomness in activity completion times.

10. PERT Contd … The basic tools used in PERT approach is the network or flow plan. The network is composed of a series of related events and activities. Events are required sequential accomplishment points in the program or project Activities are the time consuming elements of the program and actually connects the various events Many activities and events are involved in a program or a project.

11. PERT can be very useful in planning and controlling Three basic characteristics of a program or project that is amendable to the PERT approach. Activities be such that time estimate can be made There must be starting and ending points There must be parallel activities – key to PERT usefulness PERT Contd …

12. PERT Contd .. The most recognizable feature of PERT is the "PERT Networks", a chart of interconnecting timelines. PERT is intended for very large-scale, one-time, complex, non-routine projects.

13. Importance and Use of PERT A PERT chart is a tool that facilitates decision making Two consecutive events in a PERT chart are linked by activities, which are conventionally represented as arrows in the diagram above. The events are presented in a logical sequence and no activity can commence until its immediately preceding event is completed. The planner decides which milestones should be PERT events and also decides their “proper” sequence. A PERT chart may have multiple pages with many sub-tasks.

14. Decision to develop Open heart surgery Unit. Planning complete Equipment ordered Equipment received Equipment ins talled Equipment and team tested and ready Operating room gutted Renovation complete Team recruited Team hired Team trained 5-7-9 1-2-3 10-12-14 3-4-5 1-2-3 2-3-4 2-3-4 3-4-5 2-3-4 2-3-4 4-5-6 1-2-3 Critical Path 1-2-3 = Indicates, in order of listing estimates of most optimistic, most likely, and most pessimistic completion times Source: Longest , Beaufort B, Example: PERT network for developing a open heart unit

15. PERT Contd .. To make the network understandable and usable, the time between the various events (activity time) must be computed. No accurate method to estimate time, however, optimistic time (OT), most likely time (MT) and pessimistic time (PT) can be estimated Calculate activity time by dividing OT+4MT+PT divided by 6 Critical path: the path that takes the longest period of time to complete

16. Steps in the PERT Planning Process Identify the specific activities and milestones. Determine the proper sequence of the activities. Construct a network diagram. Estimate the time required for each activity. Determine the critical path . Update the PERT chart as the project progresses.

17. Benefits of PERT PERT is useful because it provides 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 Activity start and end dates

18. Limitations The activity time estimates are somewhat subjective and depend on judgment. PERT assumes that the probability distribution of the project completion time is the same as the that of the critical path. PERT consistently underestimates the expected project completion time.

19. Thank You!!!