Research Article

Sliding Window Based Feature Extraction and Traffic Clustering for Green Mobile Cyberphysical Systems

Algorithm 2

The traffic clustering algorithm.
Input: Feature vectors of all traffic distribution samples .
Output: Traffic patterns .
 (1) Normalize Feature vectors to .
  (2) Determine the number of traffic patterns by the average silhouette method.
  (3) Construct an affinity matrix with Gaussian kernel function, in which
    holds for and .
  (4) Define the diagonal degree matrix . Normalize the affinity to , and .
  (5) Compute the first eigenvectors of . Construct a matrix .
  (6) Construct a matrix from by normalizing the rows of to norm 1, and .
  (7) Treating each row of as a point, cluster them into traffic patterns by -means.
  (8) Assign the original feature vector of traffic distribution sample to traffic pattern according
   to the assigned label of the row of the matrix .
  (9) Compute the features of traffic patterns, and .