This paper presented a mathematical model with the main controlling parameters of the main points of knowledge, coefficient of difficulty and the structure of test question.

以考查点、难度系数和题型为主要控制参数建立了组卷问题的数学模型，并给出了用遗传算法解决组卷问题的新方法。

youdao

For scattering of a bounded acoustic beam from a liquid-solid interface, the principal difficulty comes from the treatment of tie plane wave reflection coefficient.

分析有限声波束从平面液-固界面上散射的困难主要发生在平面波反射系数的处理上。

youdao

Therefore, the difficulty coefficient of road administration is determined by calculating the group utility function based on the normalized weights, utility function of every expert and the indexes.

用归一化的专家权重、专家个人效用函数的权重以及标准化后的指标，计算群效用函数，即可确定公路路政管理难度系数。

youdao