asymptotictheory biomathematics calculus congresses controltheory coupledmodetheory degeneratedifferentialequations differentiabledynamicalsystems differentialequations differentialoperators diffusion dynamicalsystemsandergodictheory elliptic ellipticdifferentialequations ellipticfunctions evolutionequations fluidmechanics heat hyperbolic linearoperators masstransfer mathematicalanalysis mathematicalbiologyingeneral mathematicalmodels mathematicalphysics mathematics multipleintegrals nonlinear nonlineardifferentialequations nonlineartheories numericalsolutions parabolicdifferentialequations partial partialdifferentialequations population qualitativetheory stochasticprocesses transmission équationsdifférentiellesparaboliques