Figure 3: The analysis of key words. The mapping on key words of lncRNA; the keywords were divided into two clusters: cluster 1: “application” and cluster 2: “characteristics.” In general, the smaller the distance between two terms, the larger the number of cooccurrences of the terms. A large size of a circle represents that the keyword appears more frequently. The line means that the topics connected on the same line are separated from each other by a comma, a semicolon, or a tab. Based on the average appeared time, key words in blue presented earlier than those in yellow or red. Two terms are defined to cooccur if they both occur on the same line in the corpus file. We set the “100” uppermost appeared lines to be shown.