This paper was based on the Ganjiang Valley ‘s 50a rainfall data (1959～2010) and the WRF numerical weather prediction model rainfall to establish a new mathematical model for water level prediction in the valley through the excellent performance technique - Muskingum model parameters optimal estimation, which realized the quantification of water level forecast. In the last of this paper the rainfall data in April 2012 of this valley was used to test the new model and the experimental results show the error between the model and the observed data is varied in -15cm to 15cm, it is very small.

For the mobile cellular networks (MCN), a new analytical model which is the PH-renewal process to model is developed in this paper as a cost-effective performance tool to investigate the performance of the MCN. To the best of our knowledge, we have not found to analyze the performance of the MCN by the pure PH-renewal models. We apply the matrix-analytic approach and the PH-renewal process to explore the performance measure of the drop and block probabilities in the MCN. The numerical results show that the proposed analytical approach is more efficient than others.

This paper was based on the Poyang lake Basin’s 55a rainfall data (1959 ~2014). First, the recursive linear interpolation method was used to complete the daily precipitation observation data of 55a to establish the Poyang lake basin’s data. Then the linear regression method was used to study the change trend of Poyang lake basin: the number of days of rainfall, days of light rain, days of heavy rain, days of rainstorm and days of continuous no rainfall. The results suggest that: 1) In the past 55a, there is no apparently change trend in precipitation between the annual and flood season. The precipitation has been with cyclical fluctuations. 2) The monthly variation trends in the water level of stations in Poyang lake basin are basically in accordance with the precipitation’s trends. 3) The precipitation has similar characteristics in spatial distribution between the annual and flood season, most concentrates in Raohe basin and XinJiang basin. 4) The total number of rainy days and light rain days shows a decreasing trend, but the heavy rain days and rainstorm days increase significantly on versus. The precipitation intensity has enhanced, also the days of continuous no rainfall show an increasing trend. That is the drought flood risk increases.