The weir is one of the hydraulic structure which is supposed to be used to store water quantity against drought. To solve the disturbance of flood control caused by soil sediment and environment problems from the severance of moving sediment, movable weir is currently set up so as to solve that serious problem. There have been many studies focusing on the weir in specific target area. however, it is not applicable for all kinds of moveable weir. Therefore, In this study, experiments for moveable weir typed sluice gate are performed and hydraulics characteristics are measured depending on gate operation. According to comparison results between apron length calculated by Bligh's equation and hydraulic jump length by experiments, hydraulic jump length is bigger than apron length by Bligh's equation where oscillation jump happens. Therefore, it is necessary to set the energy dissipator up for improving stability of hydraulic structure.

Abstract-An accurate estimation of sediment discharge in rivers and streams should be solved for the appropriate river management and monitoring. In this study, a new formula which has minimum parameters considering existing ones with a concept of entropy by a probabilistic approach, was developed and mean suspended sediment concentration were estimated. Results of this new formula were verified with the experimental results which were conducted with a steady state and gradually injecting sediment (D= 105 ㎛) in a rectangular cross-sectional flume previously. The relationship between the measured sediment distribution and the estimated sediment distribution has a good agreement.Index Terms-Entropy, entropy suspended sediment parameter, mean suspended sediment concentration, Probabilistic approach.