This article studies the optimal policy of production-inventory model in which time cycling is limited and cost parameter varies in stepped variation, and the definite way of cost parameter.

本文研究时间周期有限，费用参数呈阶梯变化的生产-库存模型的最佳策略及参数的确定途径。

youdao

But men who spend a lot of time biking should make sure their bike fits them properly, wear padded cycling pants, and stand up frequently while pedaling.

但是那些长时间骑自行车的男性应该要确保车子舒适，而且要穿充气的自行车裤，并在骑乘过程中要经常的站起来。

youdao

However, a UK expert said the average man cycling to work would be unlikely to suffer fertility problems because of their time in the saddle.

然而，一位英国专业人士提出，骑自行车上班，并不会影响男性的生育能力。毕竟，骑车的时间是有限的。

youdao

His nickname sprung from his time cycling the seven-mile journey to Westminster, followed by his family's appearance on a British Rail poster promoting the transport of bikes by train.

BBC: Profile: Sir George Young

Many users have their favourite items, including the time, cycling continuously, which allows surreptitious scanning of the latest sports results while sitting in a meeting.

ECONOMIST: MONITOR

Four of the events, the marathon, the walk, cycling road race and the cycling time trial, are free.

BBC: Commonwealth Games may not pay for India