In a method for producing a high quality silicon single crystal by the Czochralski method, a lower portion of a solid-liquid interface of a single crystal growth is divided into a central part and a circumferential part, and the temperature gradient of the central part and the temperature gradient of the circumferential part are separately controlled. The invention can be used for obtaining a fraction having a high concentration of hydroxylated or epoxydised functionalised fatty acid esters, and a solvent phase containing the other non-functionalised fatty acid esters directly from the seeds of oleaginous plants. A packet assembler extracts information from each data packet, particularly fields from the header information, and uses that information among other things, to determine if the data packet is fragmented or out of order, and to associate the data packet with a session id. A product transport is provided on the intermediate portion of the product support member. The forward data stream comprises a plurality of data samples representing voice and data streams and a plurality of fixed synchronization words. In operation, the cell’s operational history is incorporated into a model.