本文根据盈亏平衡原理对酸化、压裂措施进行经济界限分析，并建立经济界限模型。
According to the principle of the balance between profit and loss, the paper analyzes the economic boundaries of acidification and fracturing and establishes the model of the economic boundaries.
依据经济评价中的盈亏平衡点，建立数学模型和成本预警机制，顺利实现成本的有效控制。
Based on the breakeven point in economic evaluation, a mathematical model and a cost-warning mechanism are established for effective control of cost.
模型计算的允许盈亏率(旱地23.4%，水稻田- 37.2%)评价表明，旱地和水稻田目前的氮素平衡基本上是合理的。
The allowable rates (23.4% for croplands and -37.2% for paddy) calculated out by mathematical appraisal model showed that, the nitrogen balances of croplands and paddies were relatively reasonable.
图书成本有一个完整的构成体系。创建图书成本管理模型，必须对图书成本、市场需求、盈亏平衡进行分析。
Starting from the reality of publication, we establish the compositive system of book cost based on qualitative and quantitative analysis of some compositive factors of book cost.
图书成本有一个完整的构成体系。创建图书成本管理模型，必须对图书成本、市场需求、盈亏平衡进行分析。
Starting from the reality of publication, we establish the compositive system of book cost based on qualitative and quantitative analysis of some compositive factors of book cost.
应用推荐