Scholarly journal articles can be identified by:
Engineering Village and Scopus are two of the best databases for general engineering research. Both are expansive, containing a multitude of scholarly, citable sources. Scopus is an indexing database. If an item in Scopus seems promising but the FullText is not available, try searching the catalog (below) or using the library's Journal and Article Locator.
Tip: If you have an article that fits your research interests and answers important questions for you, a good way to continue finding success is to read the References section to get a feel for what related works are out there. Read the citations and see if you recognize common names or publications that have come up during your search. The reverse of this is also possible. Scopus features a "Cited By" function that allows the user to see papers that have been published citing a specific work. Engineering Village and Scopus both have "Related Documents" functions, as well.
Many professional societies publish scholarly journals within their discipline. The following databases include such information, and then some. Read the descriptions to learn if your project falls into the jurisdiction of a certain society. If so, view the Standards and Other pages for more information on what these digital libraries can offer.