A groping operation apparatus is provided in which a command action can be specified by groping operation in reliable way. The method includes two steps, the learning of the dynamic with historical data based on a recurrent neural network and a subsequent learning of an optimal regulation by coupling the recurrent neural network to a further neural network. The relay node has total path loss optimized to be minimum between relay nodes included in a relay route of the data packet or between the relay node and the core node or both. On the other hand, a groove is formed on a third substrate. The error correction operation then decodes the symbols in the identified locations as erasures.