sharp notch generation for plate not working properly

When using the internal mesh for the rectangular plate, there is the option to generate a sharp notch. Originally, this should duplicate nodes to detach them from the elements at the discontinuity.

Currently, there are two bugs:

1. The coordinates of the crack are checked wrong (y-coordinates are compared with x-coordinates, line 120).
2. The duplication of the nodes break the elements (see figure).