Systems engineering and software engineering, contrasts and synergism

Systems engineers and software engineers work together in the development of modern complex systems. The two engineering cultures, the concepts, and the best practices have developed independently over four decades. Notations and naming conventions for the same things are often different. Yet the efficient exchange of engineering information and wisdom between the two professions is important to the successful development of large complex systems. The present record of success for complex computer intensive systems is that for every six systems put in operation two are cancelled; on the average, projects are 50% over schedule, and three quarters are failures that do not function as intended or are not used at all, (Gibbs 1994). Incomplete specifications, ambiguous specifications, and misunderstood specifications are a major contributor to these problems. Development of rigorous specifications that match user needs is critical. The need for synergism between systems engineering which develops specifications to meet user need and software engineering is particularly important because software portions of systems are increasingly complex and are often being coded in countries far from the country where the system is defined and utilized.