Emergency cooperative social networks (ECSNs) play a very important role in emergency management for magnitude emergencies in China recently. Based on the data set of cooperative fight against COVID-19 of the Beijing-Tianjin-Hebei region in China. using social network analysis (SNA) and asymmetric evolutionary game model. this study finds that the asymmetry between regions is comprehe... https://countryscenesaddleryandpetsuppliers.shop/product-category/western-clothing/