[IEEE 2018 Fourth International Conference on Research in Computational Intelligence and Communication Networks (ICRCICN) - Kolkata, India (2018.11.22-2018.11.23)] 2018 Fourth International Conference on Research in Computational Intelligence and Communication Networks (ICRCICN) - Selection Of Optimum number Of Sensors Of An Electronic Tongue For Efficient Classification Of Black Tea: A Combinatorial Approach Based On Discrete Cosine Transform and Artificial Neural Network