Regardless of your major, start here. Very broad subject coverage of all engineering disciplines.
Scopus is the largest abstract and citation database of peer-reviewed literature: scientific journals, books and conference proceedings. Delivering a comprehensive overview of the world's research output in the fields of science, technology, medicine, social sciences, and arts and humanities, Scopus features smart tools to track, analyze and visualize research.
This database has a mix of science and engineering content. All content is full-text.
Google Scholar - located on the Databases list
Here are 2 video tutorials on searching Compendex.
Those primary artcle databases are crucial players in your research. Create keyword alerts on your research topic and get updates, automatically, on a regular basis.