The radial-tracing algorithm and the effective earth model are discussed.

讨论了大气折射的射线追踪算法和等效地球模型；

youdao

Application of effective earth radius and methods to derive it are discussed.

对有效地球半径的推导方法和应用进行了讨论。

youdao

The eco-light is good for earth, and it's cost-effective and convenient, because it doesn't have to be changed every few months.

环保灯对地球来说是好的，而且它很省钱、方便，因为它不需要每隔几个月就更换一次。

youdao

On Earth,biological activity is very effective in making methane.

VOA: special.2009.12.30

This includes a fundamental reorientation and restructuring of national and international institutions to move to effective Earth-system governance.

UNESCO: Providing scientific leadership towards Rio+20

"This requires fundamental reorientation and restructuring of national and international institutions toward more effective Earth system governance and planetary stewardship, " they write.

BBC: Gear change on road to Rio?

This bare, sandy earth then becomes an effective rain trap - with no vegetation, water cannot be lost through transpiration (the evaporation of water from plants).

BBC: Termites 'engineer fairy circles'