Researchers developed a model to geographically visualize supply chains, and applied the model for illustrative purposes to the grain farming industry. Feb 15, 2021 By Kristen Devlin UNIVERSITY PARK, Pa. — The COVID-19 pandemic dramatically exposed the economic vulnerability of U.S. businesses, primarily because they are so interconnected: when one region experiences a labor shortage or supply interruption, adverse effects reverberate throughout the global economy. Researchers at Penn State and the Korea Rural Economic Institute have developed a model to help visualize the interconnec...