Classical epidemic model by Kermack and McKendrick
This information is part of the Business Simulation Library (BSL).
The SIR model is a classical approach in mathematical epidemiology to study the spread of infectious diseases. The model goes back to William Ogilvy Kermack and Anderson Gray McKendrick  and is also called Kermack-McKendrick-Model.
The whole population is separated into three stocks(→modelOutput):
As in the example →SimpleProductionChainIII we are using the →Diffusion component to model social diffusion, e.g., spread by contact. The
transmissionRate (β in the mathematical literature) is also sometimes called the effective contact rate which helps to understand why we have set the
inputDiffusion) at the scope of the model to establish connections for inputs to
becoming_infectedin compliance with Modelica specifications. SystemModeler will assist connections with a drop down list making this rather convenient.
Description: Value of constant output (R0.value)
Type: Time (s)
Description: Length of the infectious perid (infectiousPeriod.value)
Description: Order of the exponential delay (infected.n)
Description: The model's main output
Description: Collected (named) input for the infection process
Description: Population in the susceptible stage of the disease
Description: Population in the infectious stage of the disease
Description: The infection is spread by a process of social diffusion
Description: Time interval during which an individual is infectious
Description: Basic reproduction number for the infectious disease
Description: Effective contact rate
modelSettingsand modified plot in v2.0.0.