Dept. of Public Management,Beijing Information Science and Technology University,100192,Beijing, China 
                                            
                                            Dept. of Public Management,Beijing Information Science and Technology University,100192,Beijing, China 
                                            
                                            Dept. of Public Management,Beijing Information Science and Technology University,100192,Beijing, China 
                                            
                                            Dept. of automation, Beijing Building Engineering University, 100089, Beijing, China 
                                            
                    
                          
                 Copyright ©    Gang  Li, Yun-fa  Jia, Chun-fang  Deng, Ya-hui  Wang  et al. This is 
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                    medium, provided the original work is properly cited.