Both need know nothing about each other, but both will be used with the class module (though the form doesn't need to know anything about the class module instance).

The standard calculating module of the fluids 'physical properties and the calculating class module such as the convective exothermic coefficient at the side of flue gas are programmed.

First we discuss the structural module method to design the virtual battlefield simulators, then use class module method to discuss reusing methods in the distributed virtual battlefield simulators.