Research On The Application Of Curve Fitting Based On Genetic Algorithm In The Ballistic Meteorology

In the local wars in conditions of information technology, the meteorology still had important effect on the weapon equipment and even the war. In recent years, theoretical research on cannon firing accuracy suggested meteorological condition had become the primary factor in calculation of cannon firing accuracy. So, it was an important way to improve the cannon firing accuracy and minish the influence of meteorological conditions that analysing the errors of meteorological element, improving the detecting accuracy of meteorological data and updating the method for computing ballistic meteorolpgical element.This thesis analysed the cause of meteorological element error at full length, laid stress on researching how to fit meteorological element curve varing with the height, presented the theory and method of curve fitting based on genetic algorithm, presented the continuous function method for computing ballistic meteorological element, minishing the meteorological element error. Specific content was as follows:(1) This thesis presented the general requirement of fitting the meteorological element curve by thhe B-Spline curve with the method of least squqres, set the less control points and better fairness of the B-Spline curve as the fitting conditions, and changed the fit of the meteorological element curve to solving the optimiaztion problems with double constraint conditions by genetic algorithm.(2) The Double Population Pseudo-Parallel Genetic Algorithms with the outbreeding elitist and inbreeding replacement policy was presented. The outbreeding elitist and local optimums in every generation was copied to slave population, which was created and evolved with setting principle. And the special individuals between the master and slave population would be changed with the principle. And the the global convergence and restraint upon premature convergence of DPPPGA had been proved.(3) The thesis analysed and dissertated the detail of fitting meteorological element curve varing with the height based on DPPPGA. Firstly, the feature points of curves were picked up and the initial population was created by certain method. Secondly, the punishing factor was set up and the process of fitting curves would be executed automatically on separating level principle level by level. (4) The continuous function method of computing the deviation value of the ballistic virtual temperature and air density was presented. The meteorological element curve varing with the height was fitted by the the B-Spline curve based on DPPPGA. And the integral mean of the B-Spline curve at every level was considered as the representative value of all the meteorological element at this level. So that the error of interpolation and computing method would be overcome.(5) The continuous function method of computing ballistic wind was presented. The way of small step and large interval was used to calculate direction and velocity of the true wind. And the vector of the true wind was resoved into two scalars in the north-south direction and the east-west direction. Then the two different scalars curve varing with the height were fitted separately by the the B-Spline curve based on DPPPGA. And the true wind at fixed height could calculated from this fitting curves directly.(6) New method of processing the meteorological element was presented. This thesis analysed the error caused by meteorological element during computing cannon firing element, presented the way of using the continuous function method with precise layer weight to calculate the ballistic meteorological element at the demanding height when the cannon firing element were cpmputed by precision method, and using the continuous function method to calculate demanging meteorological element at every step.(7) This thesis analysed the defect of the current meteorological report, and pointed out that the current meteorological report could not meet the precision demand of all kinds of fire control system in conditions of information technology, then presented the way of how to improve and reform the current meteorological report.