PERTCPM By Bhupendra Ratha Lecturer S L I
PERT/CPM By Bhupendra Ratha, Lecturer S. L. I. Sc. , D. A. V. V. , Indore Email Id: bhu 261@gmail. com
PERT n Project Evaluation and Review Technique (PERT) – U S Navy (1958) for the POLARIS missile program – Multiple task time estimates (probabilistic nature) – Activity-on-arrow network construction – Non-repetitive jobs (R & D work)
Need of PERT/CPM n Prediction of deliverables n Planning resource requirements n Controlling resource allocation n Internal program review n External program review n Performance evaluation n Uniform wide acceptance
Use of PERT n In construction activities n Transportation activities n In oil refineries n Computer systemn For manufacturing electric generator machines n Medical and surgical sector n Library activities
Importance of PERT system n n n n n Reduction in cost Saving of time Determination of activities Elimination of risk in complex activities – Flexibility Evaluation of alternatives. Useful in effective control. Useful in decision making Useful is research work
History of CPM n Critical Path Method (CPM) – E I Du Pont de Nemours & Co. (1957) for construction of new chemical plant and maintenance shut-down – Deterministic task times – Activity-on-node network construction – Repetitive nature of jobs
CPM calculation n Path – A connected sequence of activities leading from the starting event to the ending event n Critical Path – The longest path (time); determines the project duration n Critical Activities – All of the activities that make up the critical path
Procedure of PERT/CPM n Develop a list of activities that make up project. n Estimate the completion time for each activity. n Draw a project network and t
Benefits of CPM/PERT n n n Useful at many stages of project management Mathematically simple Give critical path and slack time Provide project documentation Useful in monitoring costs
Limitations to CPM/PERT n n n n Clearly defined, independent and stable activities Specified precedence relationships Over emphasis on critical paths Deterministic CPM model Activity time estimates are subjective and depend on judgment PERT assumes a beta distribution for these time estimates, but the actual distribution may be different PERT consistently underestimates the expected project completion time due to alternate paths becoming critical
- Slides: 10