private List<Partion> getPartion_ByU_SubCategoryID(Clustering_Users_DAO dao, string U_SubCategoryID)
 {
     List<Partion> list = dao.getPartion_ByU_SubCategoryID(U_SubCategoryID);
     foreach (var item in list)
         item.UserCentroid = dao.getUserCentroid(item.ClusterID);
     return list;
 }