第四章尝试将粗糙集和神经网络应用于冷却塔的物料成本预估，探讨了基于粗糙集和神经网络的冷却塔的物料成本预估方法。

In chapter 4, the paper attempts to use rough set theory and Artificial Neural Network in the prediction of the material cost of the cooling tower.

youdao

如果希望某种技术在商业利用方面切实可行，首先在物料的预处理方面要求所得到的中间产品必须是容易发酵的糖份，产量高，浓度也较高，而且技术的实施成本还不能过高，还有生产过程中更不能使用有毒物质，不可以耗费太多能源，最后，所生产出来的草料油在价格方面必须能够与传统汽油一争高下。

They should not use toxic materials or require too much energy input to work. They must also be able to produce grassoline at a price that can compete with gasoline.

youdao

物料成本在很大程度上受世界市场燃料和矿产价格的制约。

Their materials costs are largely governed by prices on world markets for fuels and ores.

youdao