I am professor of astronomy at University of Massachusetts. My research has been focused on galaxy formation, large-scale structure of the universe, and cosmology. I construct models for the formation of disk galaxies, the formation and structure of dark matter halos, the connection between galaxies and dark matter halos, the structure of gaseous halos, and physical processes related to galaxy formation and evolution. I use galaxies and galaxy systems from observations and from simulations to understand the properties of dark matter halos and the distribution of dark matter in the Universe, as well as to reconstruct the current and initial density fields for the local Universe. I have coauthored a textbook on `Galaxy formation and evolution' which was published by Cambridge University Press. Please refer to my Research and Publications for details of my research interest.