Disclosed are a video encoding method and apparatus and a video decoding method and apparatus. In an example scenario, a call center maintains personal profiles of a number of clients, including contact information for persons or other entities designated by the clients to receive information about the clients. In some embodiments, the measurement technique may be selected based on the type of measurement that is desired. The slotted ring has a cutting slot, a narrow section and, a wide section. This process comprises the adiabatic nitration of benzene with a mixture of sulfuric acid and nitric acid, in which the sum of the concentrations in the reaction zone of the metal ions which form sparingly soluble metal sulfates is less than 900 mgl, based on the volume of the aqueous phase which contains sulfuric acid. The cover plate includes a pivot member along at least one edge, and the hinge piece defines a pocket for releasably receiving the pivot member.