OR(Operation Research) | Simulation | Types of Models | Advantages | Disadvantages

Simulation

Simulation is the imitation of the operation of a real-world process or system over time. The act of simulating something first requires that a model be developed; this model represents the key characteristics or behaviors/functions of the selected physical or abstract system or process.

Type of models 

Active models

Active models that attempt to reproduce living anatomy or physiology are recent developments. The famous "Harvey mannequin" was developed at the University of Miami and is able to recreate many of the physical findings of the cardiology examination, 

Interactive models

More recently, interactive models have been developed that respond to actions taken by a student or physician. Until recently, these simulations were two dimensional computer programs that acted more like a textbook than a patient. 

Computer simulators

Simulators have been proposed as an ideal tool for assessment of students for clinical skills. For patients, "cyber therapy" can be used for sessions simulating traumatic experiences, from fear of heights to social anxiety.

Programmed patients and simulated clinical situations, including mock disaster drills, have been used extensively for education and evaluation. These "lifelike" simulations are expensive, and lack reproducibility. A fully functional "3D" simulator would be the most specific tool available for teaching and measurement of clinical skills. 

Advantages

1. Simulation is best suited to analyze complex and large practical problems when it is not possible to solve them through a mathematical method.
2. Simulation is flexible, hence changes in the system variables can be made to select the best solution among the various alternatives.
3. In simulation, the experiments are carried out with the model without disturbing the system.
4. Policy decisions can be made much faster by knowing the options well in advance and by reducing the risk of experimenting in the real system

Disadvantages

1. Simulation does not generate optimal solutions.
2. It may take a long time to develop a good simulation model.
3. In certain cases simulation models can be very expensive.
4. The decision-maker must provide all information (depending on the model) about the constraints and conditions for examination, as simulation does not give the answers by itself.