Based on the profit and loss analysis model the author concluded that increasing the first year premium per capita and decreasing the variable cost ratio are the main ways to raise the management level and keep sustained growth of the business .

本文在提出电销中心盈亏分析模型的基础上指出，提高人均新保保费和降低 变动 成本 率可以从根本上提高经营管理水平，从而使经营绩效可持续增长。

A bi-linear programming model with variable cost has been established based on the production flow scheme of a refinery and the hydrofining component ratio and process cost is added in the cost target function .

根据某炼油厂柴油生产流程，在成本目标函数中加入加氢精制的组分 比例和加工成本，建立 可变 成本的双线性规划模型。