The Research On Linetype Selection Of Frequency Analysis About Design Discharge Of Xinjiang

The main method of analysis and calculation of design flood is frequency analysis, but also the important part of the engineering hydrology which has a direct impact of the safety and investment of various projects. The linetype selection is one of the important issues of frequency analysis of the hydrology; especially the extension of the rational curve directly affects the design value. Now the real work in the hydrologic design in Xingjian, linetype selection is usually based on experience, in general we take the Pearsonâ…¢distribution for theoretic linetype.On the basis of survey the damaged roads and bridges by flood in Xingjian, this article was launched for the research that if there existed a better frequency distribution model than Pearsonâ…¢in arid and semi-arid region in Xingjian.This article from the sum of squares of each of the smallest absolute value and the minimum deviation, the relative sum of squares and minimum standards for the fitting, using a variety of frequency distribution model parameter estimation method of a variety of general concept of parallel computing, combined with the causes of floods in Xinjiang , type, and the characteristics of the wide-shallow river, the six districts of the Xinjiang region of 38 hydrological stations for annual maximum flood peak discharge series of the preferred frequency distribution model, while identifying the optimal parameter estimation methods. The major results of the thesis is as follows:(1)The background of this topic and research purposes, based on detailed hydrological frequency analysis of the research progress, this article pointed out modern trends in flood frequency analysis and the advantages and disadvantages of various analytical methods.(2)An overview of Pearsonâ…¢distribution, two parameter lognormal, generalized extreme value distribution, Weibull distribution, generalized Pareto distribution, generalized Logistic distribution of flood frequency distribution model in six statistical features.(3)Traditional parameter estimation methods and The Parameter optimization theory of Simulated Annealing Algorithm, Genetic Algorithm and Particle Swarm Optimization is introduced.(4) Investigate the damaged roads and bridges in Xinjiang, Xinjiang broad and shallow, changing the characteristics of rivers and flood causes, types, have a better understanding.(5)38 stations in six districts of Xinjiang, on the basis of the maximum peak flow series data analysis system through a common frequency data for each station were used six different distribution method of five parameters, the three fitting criterion optimum curve and to determine the 38 annual maximum peak flow station optimal linear range, optimal parameter estimation methods, and calculate the optimal distribution of each station to design peak flow, and finally the design peak flow results of a comparative analysis of the frequency.