monotonic quantity meaning in English

单调函数
单调量

2 , the friction coefficient at the pitch point is not a monotonic quantity of the rational speed or the load , instead of having a maximum value . and the value of the friction coefficient is very small , its order of magnitude only being 10 - 3 . so , it is reasonable that the friction force on teeth surfaces are ignored when the gear - driven contact fatigue strength is designed
2 、当轮齿在节点啮合时，随着转速或载荷的变化，齿面摩擦系数并非呈单调变化，而是存在极值点;节点啮合处的齿面摩擦系数很小，其数量级为10一，，因此在做齿轮强度设计时，忽略齿面摩擦力的影响是有理论根据的。