cumulative probability meaning in English

累积概率
累积机率
累计概率值

The cumulative probability distribution ( cpd ) and probability density function ( pdf ) of the magnitude of signals with noise are approximated by the cumulate percentage distribution ( cpd ) and percentage density ( pcd ) respectively by sorting and discretizing . the simulation verfies the following
含噪讯号强度之累积机率分布及机率密度特性，则依强度递增排序法，换算成累积百分比分布及百分比密度近似之。