Lotka-Volterra Equations Revisited - FlowingSpecies

The Modelica By Example target code is:

within ModelicaByExample.Components.LotkaVolterra.Interfaces;
connector Species "Used to represent the population of a specific species"
  Real population "Animal population";
  flow Real rate "Flows that affect animal population";
end Species;

The exported Modelica code for interface block SpeciesFlowElement (using SysPhS-style naming) is:

model SpeciesFlowElement
  SpeciesFlowElement _SpeciesFlowElement;
  connector SpeciesFlowElement
    Population p;
    flow Rate r;
  end SpeciesFlowElement;
  type Population=Real;
  type Rate=Real(unit="1/s");
end SpeciesFlowElement;