You stay in DUS for two years – just like everyone else, as engineering majors are “pre-engineering” for two years, for example – and complete your entrance-to-major requirements. At the end of your sophomore year, you apply to your major. It is based on GPA and completing ETM (a prescribed set of courses in which you need, usually, a C or better). There is no benefit to applying from DUS or from another college. Check out ugstudents.smeal.psu.edu for more info, specifically the page “Pre-Major Planning” (http://ugstudents.smeal.psu.edu/academics-advising/get-into-a-smeal-major/pre-major-planning)