Research Article

An Efficient and Fast Model Reduced Kernel KNN for Human Activity Recognition

Algorithm 2

The working process of K-KNN.
Require: input data matrix, ; the target value, ; the parameter of K-KNN, K; the number of training data, L; the kernel parameter, .
Ensure: the forecasting output ().
Data Separation:
(1)Data matrix (X) is separated as and by equation (3) and (4), separately;
Kernel Computation Part:
(2)Calculate the kernel matrix of training features () by equation (6);
(3)Calculate the kernel matrix of testing features () by equation (7);
Loop:
(4)fordo
(5)fordo
(6)  Calculate the distance between and by equation (1);
(7)end for
(8) Sort the distance from smallest to largest value (in ascending order);
(9) Pick the top K vectors from the sorted collection as an index;
(10) Set the forecasting the class label based on the most frequent class of processed index.
(11)end for
return