The main points from this model are:
Some of the most commonly used methods for modeling of the system are:
Data Model- It is the relationship between data entities.Process Model- the focus is on identifying the flows between the entities.Behavior Model- looks at the controlled and activation of various processes in the system.
Higraphs are generalization of complex ER diagrams. An enity is considered to be a set with multiple elements called a Blob.
Dataflow Diagrams (DFD)- In the data flow diagram, we try to identify. What processing is done? When, how, where, by whom?What data is needed? By whom, for what, when?
Basic constructs of DFD are Function, dataflow, store, and terminator.
Functional Flow Block Diagrams(FFBD)- this provides a hierarchical decomposition of the system function, and show a control structure that detects the order in which the function can be executed at each level of the decomposition.
FFBD is classified into 4 categoriesSeries ExecutionConcurrent ExecutionSelection StructureMultiple Exit
Petri nets were introduced by Carl Adam Petri in 1962 this is aa diagrammatic tool to model concurrency and synchronization in a distributed system.
Some behavioural prperties are:Reachability"can we reach one particular state from another?"Boundedness"Will a storage place overflow?"Liveness"Will the system die in a particular state?"
Models are used in engineering to seek answers to questions.Engineers seek to answer these questions:Will the system design work?which of the two system designs is better?Do I adequately understand the system?What kind of trade-off I can have?
Physical modeling provides a grasp of the problem that cannotbe achieved by any other techniques.
There are various methods of modeling the system or physical systems.
Heuristic modelingmathematical modelingphysical system model(Bongraph etc)dimensional analysisnumerical modeling(Finite difference, finite element, etc)
SimulationTime-domain analysisFrequency domain analysis
Bond graph is a physical system based modeling technique.