Project management teams use various tools and techniques to create work schedules and measure the performance of their projects. Project scheduling is one of the most important process which combines time, tasks, resources and costs in a project. Basically work schedules are created by listing the activities, determining activity durations and assigning activity dependencies. Gantt Charts, Pert Diagrams and CPM are the most common scheduling techniques used for creating work schedules. One or all of these techniques can be used based on the requirements and the complexity of the project.
Most Common Scheduling Techniques
Gantt Charts are also known as bar charts. Activities are represented as bars and the length of each bar represents the activity duration. The beginning of the bar shows the start date and the end of the bar shows the end date of the activity. Depending on the project execution plan and resource availability, these bars may be sequential, or run in parallel. Gantt Charts are simple tools therefore project management teams and stakeholders can easily understand it and manage their projects by the help of it.
Critical Path Method
Activities are linked to each other by using dependencies in a network diagram. These activity groups form paths. The critical path is the longest path of the network diagram. In this method, activities are listed, activity durations are determined, dependencies between the activities are established and the longest path is identified by making forward and backward calculations. The critical path method is a visual technique which enables to show activities, activity dependencies and durations in the same diagram.
PERT Program Evaluation Review Technique was developed by the US Navy in the late 1950’ s for Ballistic Missile Program in order to find a simple system to manage and organize complex objectives and thousands of contractors. In this method, activities are listed, activity durations are determined by using three estimate techniques, dependencies between the activities are established and the longest path is identified by making forward and backward calculations.
The three estimate techniques are;
• Most Likely Estimate
• Optimistic Estimate
• Pessimistic Estimate
Gantt Charts are the simplest methods used for creating work schedules. However the critical path and the project completion date can not be determined. The critical path method demonstrates the project completion date and the activities on the critical path. The PERT method is a complicated method which makes hard to analyze the results. Employing softwares enable to create work schedules, CPM and PERT calculations easier and fastly.