Method and system for determining a measure of quality for images by using multi-level decomposition are presented. First and second metal reinforcement rings include a body contacting one of front and rear surfaces of the backing disc adjacent a central opening. Methods of producing polysilicon using such apparatus, as well as methods for applying the quartz ceramic lining onto a reactor vessel, are also provided. A high water mark is maintained for tracking the stack pointer’s farthest location from the stack base during the execution of a program. The cap may be on a proximal end of the hub and may include an opening in the cap extending radially outward from a point near a radial center of the cap through a circumferential edge of the cap. The first coupler or second coupler includes at least one engagement assistor configured to rotate the outer auger prior to engagement between the first engagement cog and the second engagement cog.