A system and method for driving a drawer of a refrigerator are provided. In the method, parameters required for coding are determined according to a coding rate and a code length, a seed matrix is generated according to values of the parameters, a plurality of cell matrices are generated according to the values of the parameters, a parity check matrix is generated using the seed matrix and the cell matrix, and information bits are coded from the parity check matrix. An electrical circuit which includes an emitting device, a receiving device and an indicating device is electrically coupled such that upon activation, the emitting device emits a beam which passes through the beam passing member. The releasable connection arrangement is configured to maintain a rigid connection between the work contact element and the extension member during normal operation of the tool. Out of the multiple communication channels, a particular communication channel is selected for each video layer, which has the minimum transmission cost over the selected communication channel. In one example, there is provided a dopant delivery device configured to supply dopants to a spectrometry system comprising a tube including a first chamber and a second chamber, a first dopant source included in the first chamber, and a second dopant source included in the second chamber.