Only young magma intrusions contain the amount of heat necessary for the heat supply of an economical geothermal field . 只有年青的岩浆侵入体才能拥有一个经济性地热田热补给所必需的热能。
This may prove to be a much easier and more economical computation, whether an analog or digital computer is used . 可以证明，不论采用模拟计算机或数字计算机，这都是一个更容易和更经济的计算方法。
More research is needed to develop effective and economical methods for ultimate disposal of concentrated waste materials removed from wastewaters . 要进一步研究从废水中去除的浓缩污泥的有效而经济的最终处理方法。
Concrete arches are an economical way to transfer loads to the ground where foundation conditions are adequate to resist horizontal loads . 当基础条件足以承受水平荷载时，混凝土拱桥确是一种能使荷载传递到地基上去的经济有效的桥型。
A microprocessor can be used with a balance, weight set, and beaker to provide an economical and accurate measure of engine fuel consumption rate . 微处理机可以与一个天平、砝码和量杯一起使用，以实现对发动机燃料消耗率的经济而精确的测量。
It has been the responsibility of the engineers to synthesize this basic knowledge into practical systems of wastewater treatment that are effective and economical . 工程师们的任务就是把上述基础知识综合运用到经济有效的实际废水处理系统中去。
The developing of economical embed numericalcontrol system 嵌入式数控系统的研发
The theory and methodl of regional economical planning 区域经济规划的理论与方法
Some questions about building an economical society 关于构建节约型社会的几个问题
Economical operation of pumped storage station online 抽水蓄能机组在线经济运行
