Based on the three basic principles of hydraulics,a discharge correlationequation and a new submergence standard for automatic turning gate controlled by hydraulic pressure are established.

Based upon the basic principle of hydraulics and the critical submerged theory presented,a critical submerged flow for broad crested weirs is studied,and the theoretical formula of critical submerged criterion for broad crested weirs which the results of computation coincide with the present experimental criterion is obtained in this paper.

This paper presents the experiential study on casingcutting with abrasive water jet under conditions of nonsubmergence, submergence and ambient pressure.

②The size and inundation of the reservoir can be expounded and proved through economic benefits.

A New DEM-based Method for Flood Area Calculation and Damage Evaluation;

Based on grid of DEM, we take the lower reaches of Weihe flood data as a basis, and combined with Virtual GIS module of ERDAS 8.

Correct flood simulation of intertidal zone is crucial to marine applications such as coastal management and anti-flood.