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According to underwater terrain characteristic, the multi-index synthetic evaluation theory is used for calculating matching area of an underwater terrain-aided navigation system in this paper. Considering the terrain elevation standard deviation, roughness, terrain correlation coefficient, topographic information entropy and other crucial terrain characteristic parameters on the effect of navigation...
Due to long-term exploration with insufficient conservation, the resources and environment in Heilongjiang state farms (HSFs) have been impacted and influenced to some extent. However, the environmental problem of HSFS has received minimum attention, so it is very important to evaluate the environmental production efficiency and the productivity of HSFs. In this article, methods of Data Envelopment...
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