SUMMARY

Using Lagrangian polynomial to interpolate monitoring data and forecast groundwater regime

 

Đặng Hữu Ơn, Nguyễn Chí Nghĩa

 

The Lagrangian polynomial is being largely used to found relations between function and variable from factual observations or test data. When adjusting monitoring data we need to define the change law of regime factors following space and time. Basing on experience data we have been using the interpolation by the Lagrangian polynomial for solving this problem. The Lagrangian polynomial has the following form:

P_n(x) =

Using the Lagrangian polynomial we can determine the function demonstrating the relation between the groundwater table and the distance from boreholes to river. From these results the following conclusions may be drawn:

- When adjusting the groundwater monitoring data the Lagrangian interpolation allows to determine the change law of regime factors (elevation of water table, discharge, temperature, chemical composition of water, etc.) by space and time, as well as by the change of factors influencing to the regime.

- The combination between the Lagrangian interpolation and statistics allows to extrapolate the tendency for forecasting the development of groundwater regime by space and time.

        

Ngày nhận bài: 28-5-2004

Người biên tập: Trần Minh