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Dynamic slack-based measure model efficiency evaluation of the impact of coal mining characteristics
Peng Wu1, Yiqing Wang1, Chenyang Jiang1
1Business School, Sichuan University, Wangjiang Road No. 29, Chengdu, 610064 People's Republic of China.
Abstract:
Chinese coal enterprises are facing severe challenges due to low-carbon economy requirements and capacity reductions. This paper adopts a dynamic SBM model to compare the mining efficiency of each mining area of a coal company in China. We use total excavation footage, number of working platforms, and machine quantities as input indicators, and coal sales and CO2 emissions as output indicators. It was found that (1) both high efficiency and low efficiency mines maintained their production status each year and did not actively improve over time; (2) energy consumption was the primary indicator affecting comprehensive mining efficiency; and (3) while changes in the market environment did not have any significant impact on coal mining efficiency, coal mine characteristics were found to have some correlations with efficiency.
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