In this study, PM2.5 was analyzed for heavy metals at two sites in industrial northeast China to determine their sources and human health risks during heating non-heating periods. A positive matrix factorization (PMF) model determined sources, US Environmental Protection Agency (USEPA) entropy weight methods were used assess risk. metal concentrations higher the period than period. period, coal...

The development of the digital economy has become a new way to respond epidemic impact effectively. With innovative breakthrough information and communication technology, real economies are deeply integrated. an important driving force for transformation economic momentum development. Panel data from 31 provinces in China 2010 2019 were selected analysis. In first stage, study constructed evalu...

Analyses the current road pavement maintenance technical specification, put forward a new evaluation method for maintenance and overlay of old asphalt pavement. Considering the uncertainty and complexity in the process of performance evaluation, and based on the entropy and the Kohonen network theory, the performance evaluation system is established in Kohonen network of fuzzy entropy method, c...

â â  the present study attempts to investigate the urban hierarchy in iran between 1996-2006. the research method is content and statistical analysis. the necessity data were collected by documental method. in addition to the analysis and sorting of the data regarding the situation of iranian cities based on different models such as entropy ,ginny coefficients, urban concentration index, and ra...