Systems engineering as a ‘hard’ methodology has its roots in NASA and the early space projects of the 1960s. One of its more generally applicable variations is again presented by Flood and Carson (1988). It has four main phases: systems analysis, systems design, implementation and operation. The phase of systems design in this case belongs to a typically hard systems methodology. It should therefore not be compared with the same phase in van Gigch’s approach presented earlier in this chapter.
Phase 1: Systems analysis
- Recognition and formulation of the How did the problem arise?
Who are those who believe it to be a problem?
Who decided to implement a planning decision?
Is the problem the right one?
Will it save money?
Is it better to spend the money elsewhere?
- Organization of the project — A team composed of:
A team leader
Users
Model builders
Designers
Computer programmers
Mathematicians
Economists
Accountants
- Definition of the system
Breaking down into subsystems and identifying the interactions using flow diagrams representing:
money
energy
materials
information
decisions
- Definition of the wider system
The role of the system within the wider system of which it is a part, depicted in a flow diagram.
- Definition of the objectives of the wider system
By use of block diagrams from the system and the wider system, sets of objectives regarding the wider system can be formulated.
- Definition of the objectives of the system
Initially, these are dictated by the needs of the wider system. Conflicting objectives should be listed and ranked according to their importance. Definitions in economic terms should be used and the efficiency in reaching the objective calculated.
- Definition of the overall economic criterion
This economic criterion should be directly related to the objectives. Conflicting objectives could be handled by applying a weighting factor to each.
- Information and data collection
Data-gathering for future modelling of the system and forecasting of the future environment. Use of statistics.
Phase 2: Systems design
- Forecasting
This should be done regarding potential demands, potential activities, and environment for the short, medium and long-terms.
- Model building and simulation
Predicting the performance in potential operating conditions and real life environments.
- Optimization
Identifying the most favourable model performance according to the economic criterion chosen for the study.
- Control
The solution is checked by different kinds of control loops.
Phase 3: Implementation
- Documentation and approval
A report highlighting the implementation and its critical path should be prepared. This should be approved by all influenced by the planned change.
- Construction
Creation of hardware and software regarding special control and optimization systems according to a pre- planned schedule. Construction of the main system.
Phase 4: Operation
- Initial operation
Enhancing the cooperation between the systems team and the systems users in connection with the delivery of the system. Use of adequate documentation and training of personnel.
- Retrospective appraisal of the project
Making a report of the whole project. Prospective reoptimization of the project.
Source: Skyttner Lars (2006), General Systems Theory: Problems, Perspectives, Practice, Wspc, 2nd Edition.