,Modelling & Simulation 2
Week 1 Statistics
What is simulation?
- imitation of the operations of a real-world process or system,
over time.
- methods and applications to imitate or mimic real systems,
usually via computer.
What is DES ( discrete - event system) simulation?
Discrete-event simulation is concerned with
- modelling of a system as it evolves over time by a representation in
which the
- state variables change instantaneously at separate points in time.
Continious Discrete
,Modelling & Simulation 2
Week 1 Statistics
DES:
Stochastic:
Some state variables are random
Dynamic:
Time evolution is important
Discrete:
System state changes when an event occur (that is: significant changes
occur at discrete time instances )
Where is DES used?
• Analysis of passengers or baggage flows in an airport terminal
• Runway capacity planning
• Airport gate assignments
• Flight scheduling
• Crew scheduling
• Fleet assignment
, Modelling & Simulation 2
Week 1 Statistics
Steps in simulation:
1. Problem formulation
2. Setting objectives and overall project plan
3. Model conceptualization
4. Data collection Phase 1: initial phase
5. Model translation Phase 2: model building &
6. Verification Data collection
7. Validation Phase 3: run the model
8. Experimental design Phase 4: implementation
9. Production runs & analysis
10. More runs ?
11. Documentation and reporting
12. Implementation
Verification & validation of the models
Verification Validation
• Building the model correctly • Building the correct model
• Model has the right input and • Accurate representation of
structure the real system
• Performed during building the • Performed after finishing
model the model
Week 1 Statistics
What is simulation?
- imitation of the operations of a real-world process or system,
over time.
- methods and applications to imitate or mimic real systems,
usually via computer.
What is DES ( discrete - event system) simulation?
Discrete-event simulation is concerned with
- modelling of a system as it evolves over time by a representation in
which the
- state variables change instantaneously at separate points in time.
Continious Discrete
,Modelling & Simulation 2
Week 1 Statistics
DES:
Stochastic:
Some state variables are random
Dynamic:
Time evolution is important
Discrete:
System state changes when an event occur (that is: significant changes
occur at discrete time instances )
Where is DES used?
• Analysis of passengers or baggage flows in an airport terminal
• Runway capacity planning
• Airport gate assignments
• Flight scheduling
• Crew scheduling
• Fleet assignment
, Modelling & Simulation 2
Week 1 Statistics
Steps in simulation:
1. Problem formulation
2. Setting objectives and overall project plan
3. Model conceptualization
4. Data collection Phase 1: initial phase
5. Model translation Phase 2: model building &
6. Verification Data collection
7. Validation Phase 3: run the model
8. Experimental design Phase 4: implementation
9. Production runs & analysis
10. More runs ?
11. Documentation and reporting
12. Implementation
Verification & validation of the models
Verification Validation
• Building the model correctly • Building the correct model
• Model has the right input and • Accurate representation of
structure the real system
• Performed during building the • Performed after finishing
model the model
