Iben 9417156 Stellar modeling calculations will be performed on a variety of phases in the lifetimes of certain classes of stars. These are well-observed cases which have not yet been modeled nor explained satisfactorily. They include low-mass asymptotic giant branch stars, stars with 9 to 11 solar masses, white dwarfs in the late stages of stellar evolution, symbiotic variable stars, cataclysmic variable stars, and mass transfer in close white dwarf-helium star binaries. ***
