Project Management : PERT/CPM for Indian Students

This lecture and next two are taking you to the depth of the subject, by introducing to you the concept of floats and methods of calculation of them. Floats apply to only activities which are not on the critical path.

Here I am introducing you to the concepts of Early start, Late start, Early Finish and Finish and teaching you how to calculate them step by step. These four calculations will ultimately take you to the calculation of Free Float and Total Float in the next lecture.

In the earlier lecture we have covered Early Start (ES), Early Finish (EF), Late Start (LS) and Late Finish (LF). Now those data will be used first to calculate the Total Float (TF) and then to calculate Free Float(FF) . This will help us to identify which are the jobs that are on critical path. In fact in those jobs both TF and FF will be zero. The jobs that are not on critical path can have different FF  and TF. FF is a sub set of TF So FF can not be greater than TF.

Here I am showing you how to validate the Critical path, Total Float and Free Float by using the Excel model that you have downloaded earlier. Here in the resources section, I am giving the same file so that you can download it again.

Here I am explaining a CPM simulation module in Excel which you can download from the resource section and use it. You need not be a Excel expert to use it. There are only certain cells in the model relating to time dimension of each activity, which you can change and see the effect on the overall project. In certain case your experiment may reduce or increase the date of completion of the project and in certain cases it can even change the critical path.

In this lecture I am explaining the basics of PERT or Program Evaluation and Review Techniques. This concept will be reflected later in numerical problems in later lectures.

Here I have taken a PERT related question from a University examination and solved the same before your eyes. I have used Excel for calculation, but you can use calculators also to do the same calculation. The line diagrams shown there can also be drawn by hands.  I have also uploaded the calculation as a PDF file in the resource section of this lecture.

The last lecture had Activities on Node (AON). Although I am a get believer of AON, my training will remain incomplete if I do not convert this AON into Activities on Arrows (AOA). This is exactly what I have done in this lecture. 

In this lecture I am trying to give you an idea on how targets are fixed in a PERT environment and the same is communicated to the team with an upper and a lower time threshold, so that everyone is in sync with the implementation of the project.

In this lecture the concept of crashing of project duration is being discussed. In the next lesson you will see the numerical examples.

Here I am explaining the concept of cost slopes, which are so essential for setting priorities for crashing of jobs or activities on the critical path.

While you crash a project, you incur additional expenses. That is why we calculated cost slopes in the last lecture. But there is also a saving. You save in terms of administrative cost which is normally a fixed amount per unit of time. Suppose your project is implemented in weeks and you have a weekly admin expense of 100, if you crash the project for 5 weeks, you incur some extra expense, but you also save 100 x 5 = 500.

In this lecture I have explained step by step crashing of project duration. Here you will also see how critical path changes during crashing of project duration. The relevant model can be downloaded from the resource section of this lecture.

Here I have provided links to my other useful courses.