Diameter-class

基本解释

In order to forecast accurately height of each diameter class of poplar in Jiangsu Province,the quadric parabola function with five parameters was established.
用江苏省杨树解析木编制了杨树标准树高曲线模型,该模型引入了适宜的林分控制因子(树龄和地位指数),是具有统计学意义的树高曲线模型。
Study on Estimation of Stand Diameter Class Volume and Merchant Volume
林分径阶蓄积量与材种出材量测算的研究
This lens can magnify 20 diameter.
这个透镜能放大20倍。
Kindly send us two samples of each class quote for.
报价时，请对每一个等级的各寄两个样品。
The diameter of the tree-trunk is about 2 meters.
这树干的直径大约是2米。