A hardness tester includes a supporting frame having a guiding channel, a driving axle slidably disposed in the supporting frame, and a penetrating pin, having a pin head, coaxially disposed in the guiding channel in a slidably movable manner to coaxially align with the driving axle for the pin head to penetrate on a testing surface of a tested object. In one implementation, the structure includes a substrate having base electrodes and gate electrodes coupled thereto and insulated from each other, and an emitting material deposited on active regions of the base electrodes. The stub in the higher tier is correctly restored using the higher-tier information thus recorded. Also provided are catalyst compositions, processes for forming catalyst compositions, and polymerization processes utilizing the catalyst compositions of this invention.