Modeling and simulation of systems Simulation languages Slovak University of Technology Faculty of Material Science and Technology in Trnava

Semantics of simulation languages  Semantics of language is the meaning or sense of texts which were created according to the right syntactic rules  Semantics is given by the compiler  Semantics of programming language represents rightly created sets of algorithms  The sets of these algorithms is called universe of semantics

Basic classification of simulation languages  According to elements of dynamic system which is simulated:  Elements which stay during all the simulation period in the system are called activities  Elements which input and output during the simulation from simulated model. These elements are called transactions.  Then dynamic systems are divided into the systems of type A, type T or AT according to presence of activities, transactions or both.

Basic classification of simulation languages  We also divide simulation languages into types in accordance with the previous :  A  T  AT  TA  We recognize languages AT and TA according to element which is the bearer of actions. The bearer is always in the second place.

Division according to state changes of the system  Languages for:  Continuous simulation  Discrete simulation  Combined simulation

Typical means of simulation languages  Planning systems  Means for solution of conflicting situations  Means for generating and disposal of transactions  Means for definition of the standard repetition of simulation runs.

The planning systems in simulation languages  Interrogative planning system Interrogative planning system includes typical planning statements. These statements have the shape as e.g.: “wait T”, “hold T”, “advance T”  Imperative planning system it uses events calendar  Automatous planning system the parameter of time delay is equal in all elements

The means for solution of conflicting situations Simulation languages have to have the possibility to solve the conflicting situation, it means that statements have to be realized at the same time for different elements of system. It is necessary to provide statement in such way that the statement is realized but simulation time is not changed. The easiest solution is to apply the priority system or to define ordered events calendar.

Generating and disposal of transactions  Division of transaction one transaction causes the origin of transaction of the same class with the similar values of attributes ( in a similar way of cells division)  Generating from the source or generator

Simulation software  Simulation languages – universal usage  Simulators – oriented to specific problem area  Simprocess - CACI  Witness - Lanner Group  Simple ++ AESOP, GmbH  Arena - Rockwell Software  Simul8 – Simul8 corporation

The areas of simulation software usage  Production, supply chain  Designing  Planning and control  Services  Banks  Shops  Transport

The criteria of simulator evaluation  Area of usage  System's requests  OS  RAM  Building of model  Graphical design of model (Icons, drag&drop)  Programming  Program debuggining  Object templates

The criteria of simulator evaluation  Visualization of the process  Animation  Animation in real time  Export of animation (mpeg)  Price  Support and maintenance  Dealer

Development of simulators  Minimizing of programming  Object oriented graphical environment for model building with animation of simulation run  The possibility to add interface for graphical support (plug-in modules)  Hierarchical model building  The possibility to realize outputs of results into spreadsheets  Tools for results analysis  Cost analysis  statistics  reports  Specializations to problem areas

Development of simulators  Plug-in modules  Model documentation  Optimization  Virtual reality  Cooperation with other software products