SimulationSimulation

Presented by:Presented by: Bulbul SharmaBulbul Sharma Tanvi GuptaTanvi Gupta

ContentsContents

Simulation-meaningSimulation-meaning Steps in simulation processSteps in simulation process Advantages Advantages DisadvantagesDisadvantages Comparison of simulation Comparison of simulation

system with programming system with programming languageslanguages

Simulation-MeaningSimulation-Meaning

Simulation is a process of designing Simulation is a process of designing a model of real systema model of real system

conducting experiments with this conducting experiments with this model model

purpose of understanding the purpose of understanding the behavior for the operation of the behavior for the operation of the system.system.

System:System: Collection of entities, ex- people and Collection of entities, ex- people and

the machines that act and interact the machines that act and interact towards the accomplishment.towards the accomplishment.

State: State: Collection of variables necessary to Collection of variables necessary to

describe a system at a particular describe a system at a particular time relative to the objective of study.time relative to the objective of study.

-System can be discrete and -System can be discrete and

continuous.continuous.

Steps in Simulation ProcessSteps in Simulation Process

Formulate the problem and plan the studyFormulate the problem and plan the study

- problem of interest is stated by manager- problem of interest is stated by manager

- meeting conducted - meeting conducted

-overall objective of study and other issues -overall objective of study and other issues discusseddiscussed

-time frame for the study and required -time frame for the study and required resourcesresources

Collect the data and define the modelCollect the data and define the model

-collect information on the system layout -collect information on the system layout and operating proceduresand operating procedures

-Is the conceptual model valid?-Is the conceptual model valid?

Construct a computer programs and Construct a computer programs and VerifyVerify

-in programming languages( -in programming languages( cc++ or ++ or

FORTRANFORTRAN

-Simulation software (WITNESS, STELLA) -Simulation software (WITNESS, STELLA)

Make Pilot RunMake Pilot Run

Is the Programmed Model ValidIs the Programmed Model Valid

Design experimentsDesign experiments

Make production runMake production run

Analyze output data.Analyze output data.

Document, present and use resultDocument, present and use result

AdvantagesAdvantages

Estimates the performance of Estimates the performance of existing system existing system

Maintain much better controlMaintain much better control Allows to study a system with long Allows to study a system with long

time frametime frame Useful for sensitivity analysesUseful for sensitivity analyses Used as pre-test to try new policies Used as pre-test to try new policies

and decision ruleand decision rule

DisadvantagesDisadvantages

Some simulation may take longer Some simulation may take longer period of time to developperiod of time to develop

Produce different result in repeated Produce different result in repeated runrun

Does not generate optimal solutionDoes not generate optimal solution User has to provide all constraint User has to provide all constraint

Simulation packages Vs. programming Simulation packages Vs. programming languageslanguages

Provide most of the featuresProvide most of the features Result significant decrease in time Result significant decrease in time

and production costand production cost Provide natural framework for Provide natural framework for

simulation modelingsimulation modeling Easier to modify and maintainEasier to modify and maintain Detection of error and automatically Detection of error and automatically

checkedchecked

Advantage of programming Advantage of programming languages over Simulation softwarelanguages over Simulation software

Most modelers already know Most modelers already know programming languages but not programming languages but not simulation softwaresimulation software

require less execution timerequire less execution time Greater flexibilityGreater flexibility User friendlyUser friendly Cost should be lowCost should be low