47Nxx Miscellaneous applications of operator theory

47N10  Applications in optimization, convex analysis, mathematical
               programming, economics
47N20  Applications to differential and integral equations
47N30  Applications in probability theory and statistics
47N40  Applications in numerical analysis, See also {65Jxx}
47N50  Applications in quantum physics
47N55  Applications in statistical physics
47N60  Applications in biology and other sciences
47N70  Applications in systems theory, circuits, etc.
47N99  None of the above but in this section