first order level meaning in Chinese

精密水准仪

This paper analyzes the principle , error sources and precision of triangulated height surveying , points out the key problems about first order leveling replaced by triangulated height surveying ; and for the first time puts forward that in some given conditions , it is not only feasible but also valuable to replace first order leveling by precise triangulated height surveying , and proves it by experimentation as well
摘要通过对三角高程测量的原理、误差来源及精度分析，指出了用三角高程测量代替一等水准的关键问题，第一次提出了在特定条件下用三角高程测量代替一等水准是完全可行的，并在生产实践中得到了验证。