Project Networks

Abstract

Projects involving more than a few people, including different specialists, benefit from careful planning and control. This is true whether the project is the construction of a house, the launching of a new product or putting a satellite into space. Any such planning system should (Lock, 1971)

• (1) ensure that the project is based on feasible objectives and that individual tasks (or activities) are sequenced in a technologically feasible order;

• (2) have a proposed schedule based on reasonably reliable estimates for the duration of each task;

• (3) be capable of highlighting exceptions: when a task is behind schedule, expenditure is higher or lower than expected, etc.;

• (4) be flexible to change when things go wrong;

• (5) be matched to available resources, taking into account the requirements of concurrent projects.

For simple projects bar charts may be appropriate, but for more complex ones the critical path method (CPM) is to be preferred. Network aspects of this and related methods are brought together in this chapter, and presented in a graph theory context. For the wider aspects of project management the reader is referred to one of the specialist books (for example, Battersby, 1967, Moder and Phillips, 1970, Lock, 1971 and Burman, 1972). Elmaghraby (1977) may be consulted for a theoretical treatment of the area and for further information on resource allocation.