Hydrometer: An instrument used for measuring the specific gravity of a liquid or solution.
比重计：量度液体或溶液的比重的仪器。
2
Exact solution of a statistical model for laser beam scattering from diffusing surface has been obtained, the comparison with the approximation of center of gravity has been made.
本文对激光束在漫射表面上散射的一类统计模型给出了严格解，并与“质心近似”所得结果作了比较。
3
This article introduced the the solution procedure of structure stress by finite element software ANSYS, represent the application of ANSYS, at last we finished the stress analysis of a gravity dam.