It is hard to build a precise math model for counter-gravity casting process for its time lag, uncertainty and complexity.

由于反重力铸造过程的时滞性、不确定性、复杂性，难以建立精确的数学模型。

youdao

This paper introduces the craft characteristics of casting the shell of the gearbox, including the manufacturing of the resin moulding, the application of the hard sand core and so on.

针对变速箱壳体毛坯铸造的工艺特点，介绍了其树脂模具的制造、树脂自硬砂砂芯应用等关键环节的技巧和做法。

youdao

The cast precious metal alloy or master alloy has been found to have a reduced number of hard spots and reduced silicon contamination when compared to conventional casting methods.

当与常规铸造方法相比时，发现铸造的贵金属合金或母合金具有数量减少的硬点和降低的硅污染。

youdao

There is no open casting for actors in Saudi Arabia and it is hard to find either women or girls to appear on film because it is regarded negatively by conservatives in the country.

BBC: Haifa al Mansour becomes first female Saudi director