The concept of a selection loop

The cycle, also called the loop, is a general term for some operations that are close in nature and closely related. The intermediate products generally circulate in the loop. Usually means:
1. A general term for each job that selects a product. The crude is selected fro

Soil nutrient abundance index

The indicator of soil nutrient abundance is a correlation form between soil nutrient measurement value and crop yield measured by soil nutrient analyzer. Soil nutrient abundance indicators can be calculated from the ratio of the soil's