The conceptual (or activity) model contains all the activities that the relevant system would have to perform. The model is usually drawn as a block diagram.
The objective of the comparison stage is to relate the conceptual model to the problem situation as depicted in the rich picture.
The idea is to highlight differences between the two so that potential improvements to the problem situation can be identified.
The comparison undertaken in the previous stage can have two results.
• It can cause opinions to change on the problem situation and the issues arising from it.
• It can provide an agenda for change.
In either case (though both may result), the objective of this stage is to debate, with all concerned, the changes proposed to ensure that they are both desirable and feasible. The aim is to arrive at consensus about the proposed changes.
However, as the soft systems approach specifically attempts to explore and reconcile different views and perceptions of the problem situation, this may not be totally achievable. Thus, soft systems seek accommodation between these different views to enable action to be agreed.
Finally, the agreed changes are implemented.
Like the hard systems approach, soft systems methodology is not seen as a ‘one pass’ procedure, but as a learning process. Iteration is a feature of the methodology's application. Learning is achieved in both approaches by the use of models, although soft systems has subsequently been enhanced to include a specific analysis of the culture and politics of the problem situation, as shown in Figure 38. This is important if changes are to be culturally feasible and politically acceptable. Combining these two approaches in soft systems leaves us with a picture of it as a learning system, as shown in Figure 39.
The two systems methodologies provide a framework for the application of problem solving, analysis and design techniques.
These fall into three groups:
• Diagramming: ranging from single systems maps to complex flow charts. Diagrams of one sort or another provide a method of analysis, design and communication.
• Modelling: simulation is used extensively to analyse the dynamics of an existing system and to predict the behaviour of a proposed one. Financial models are created to justify expenditure.
• Creativity: solving problems, large or small, requires creative thought. Various creativity techniques are commonly used in systems work.
• This topic has introduced the systems approach, which is the foundation of systems engineering. The systems approach consists of three elements:
1. A set of concepts that can be used to understand the structural and dynamic features of operations systems.
2. Methodologies for managing change. Two current methodologies have been presented: the hard systems approach can be applied in situations where there is a measure of agreement about the problem to be addressed and the soft systems approach is used where there is no agreement about the nature of the problem.
3. A set of techniques that are applied within the context of a methodology.
• The systems approach in various forms will be used, either explicitly or implicitly, as the basis for all of the other material in this course.