Setting the value to once is useful if a constraint is static once initialized, as it will then only be evaluated once and increase efficiency.

如果一个约束在初始化之后一直是静态的，那么可以将这个值设为once，这样可以使约束只计算一次，可以提高效率。

youdao

In 1925 only 1, 100 Kings were counted at St. Andrews Bay; since then there has been a 300-fold increase in the rookery.

据1925年在圣安德鲁斯海湾的统计，这里只有1100只王企鹅；此后这块繁殖地中王企鹅的数量增加了300倍。

youdao

And if we consume it at the present rate, 3% or increase maybe by only three percent per year, then we won't have any left in less than 100 years.

如果我们继续以现在的速度消耗下去，或者也许每年只增长,则我们在不到100年的时间里,将变得一无所有。

youdao

Noticing the circadian pattern of Charles B's depression, Dr Wehr asked him to get through a night without sleeping, and then to increase his nightly sleep only gradually, so that for almost a week he was awake during those crucial early-morning hours.

ECONOMIST: People, like all living things, are four dimensional

We have already shown that there is nothing in its character or uses that should prevent a corresponding increase of consumption, but, on the contrary, which would rather induce a greater increase: then the only other consideration is, would the facilities of obtaining supplies have been as great?

ECONOMIST: Sugar

It then leased back properties on increase-only rental agreements.

FORBES: To Whom Do I Owe a Duty of Care?