Modeling and simulation of systems

Model building

Slovak University of TechnologyFaculty of Material Science and Technology in Trnava

The general stages of simulation models building

Definition of static structure Proposal of dynamic features Definition of stochastic features of model

(generation of random quantities) Realizing of output data or recording of state

changes Design and realization of model experiments Output and presentation of results Other functions – control, monitoring

Steps in a simulation study

Problem formulation Customer has to clearly define the problem

which should be solved by simulation Supplier (solver) has to be sure that the problem

was understood correctly The preparation of participants of project –

selection of stuff The goals and plan of project

Time plan Stuff Hardware and software Project costs

Steps in a simulation study

Design of conceptual model It is an abstraction of the real systems

which include mathematical or logical relationships of entities.

Has to independent on implementation language an architecture of computer

Determination of simulative systemDetail level Identification of system elements and

elements relationships

Steps in a simulation study

Data collection Important step – remember „Garbage In –

Garbage Out “ Input data have to represent the realityThe types of data and their format, description

of random input variables, selection of types of distributions are defined

Transformation of conceptual model into computer model

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Steps in a simulation study

Verification of computer model Defines if the computer interpretation of

conceptual model is right Validation

Defines if the conceptual model can substitute the real system for planned experiments

Design of experiments It is necessary to define for each scenario:

The length of simulation The number of runs and their repetitions Initialization setting

Steps in a simulation study

Experiments realization Each simulative run has to provide quantitative

evaluation of characteristics for given scenario Results analysis Presents the bases for results understanding.

Each results has to be documented Synthesis of knowledge

The results of analyses have to be summarized into clesr formulations

They provide alternatives for decisions processes

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