An articulating deck mower comprises a frame unit, relatively movable cutter decks, and a deck height adjuster. The test apparatus and test method can be used for quality control purposes and for evaluation of experimental or new candidates for primary backing mats for making interim tufted products for carpets that are more resistant to tuft or loop defects. In addition, the client receives a secure area access password from the server, accesses the secure area by using the received access password, and performs a remote management through a DM command received from the server. The fatty acid alkyl ester rich stream is then purified to produce a purified biodiesel product and a glyceride rich residue stream. A second dielectric layer is formed over the metallic layer. Accordingly, the method can minimize loss of a silicon substrate by DHF and can thus control the depth of a moat.