Evolution of Trending Topics in Mechanical Engineering Research Theses

Abstract

As new concepts and technologies emerge, researchers in mechanical engineering have focused on various areas of study. This thesis seeks to understand the evolution of research topics over time and identify which subjects have been favored at different points.

To accomplish this goal, the titles of MIT Mechanical Engineering theses were analyzed to measure the frequency with which certain keywords appear each year. Text data from theses published between 1975 and 2021 (inclusive) was collected from two MIT websites using an automated script. Using R, the text data was broken up and processed to count the number of occurrences of a particular word in each year. To account for differences in the amount of available data each year, the annual number of occurrences of a word was normalized by the total number of words that appeared that year.

Through this analysis, several interesting trends are revealed. Key words and phrases tend to have small time windows (about 5 to 10 years) where they experience heightened popularity and then see decreased usage. This likely represents a rise in research interest when a technology is novel, followed by a decrease in interest once the technology becomes commoditized or obsolete. Furthermore, we will take a deep dive into trends in manufacturing technologies and explore a case study comparing various manufacturing techniques. We take particular interest in additive manufacturing as the research interest in this topic has grown in recent years.