  Although the scientific digital library is growing at a rapid pace,
scholars/students often find reading Science, Technology, Engineering, and
Mathematics (STEM) literature daunting, especially for the
math-content/formula. In this paper, we propose a novel problem, ``mathematics
content understanding'', for cyberlearning and cyberreading. To address this
problem, we create a Formula Evolution Map (FEM) offline and implement a novel
online learning/reading environment, PDF Reader with Math-Assistant (PRMA),
which incorporates innovative math-scaffolding methods. The proposed
algorithm/system can auto-characterize student emerging math-information need
while reading a paper and enable students to readily explore the formula
evolution trajectory in FEM. Based on a math-information need, PRMA utilizes
innovative joint embedding, formula evolution mining, and heterogeneous graph
mining algorithms to recommend high quality Open Educational Resources (OERs),
e.g., video, Wikipedia page, or slides, to help students better understand the
math-content in the paper. Evaluation and exit surveys show that the PRMA
system and the proposed formula understanding algorithm can effectively assist
master and PhD students better understand the complex math-content in the class
readings.
