How to refine this sentence？ Clausen [11], Miller [12] and Corona [13] studied the influence of loading path, friction, tension and pressure on the sectional deformation and springback, in order to reduce the deformation and springback to a minimum through optimizing the forming process.

Is the expression of the following simple sentence nice, and how to improve? Too many preposition? The springback amount of H-bending is too small to measure, so it is not used to verify the reliability of the H-bending FE model.

Is the following long sentence awkward? How to express is better? Please help. The sentence is " In addition, the stress difference before and after retracting mandrel is calculated, and it is found the reduction of the stress magnitude caused by retracting mandrel becomes larger with the increase of the core number, thus the reduction extent of springback angle in Table 1 nearly increases with the number of cores."