Comparative analysis on convexity methods for proving blowup

In this paper, we consider three different convexity methods for proving blowup. First, we show principles of three different convexity methods by giving two lemmas. Then, by using respectively the three convexity methods we obtain the blowup result. Finally, we compare this three ways. This work aims to provide clear and comprehensive analysis for the researchers who are interested in the well-posedness of nonlinear evolution equations.