Mathematics Department of Nanchang University, Nanchang,Jiangxi, China, 330031 
                                            
                                            Mathematics Department of Nanchang University, Nanchang,Jiangxi, China, 330031 
                                            
                                            Research Center for Quality & Reliability of Nanchang University,Nanchang ,Jiangxi, China ,330031 
                                            
                    
                          
                 Copyright ©    Ruliang  Liu, Qiuxian  Dong, Weidong  Liu  et al. This is 
                    an open access article distributed under the Creative Commons Attribution 
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