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Drought is one of the most serious hazards that has more effect on human societies than the others. Scentific researches have important roles in drought planning and management of water resources, especially in time of crisis and predicted big event by the event that the crisis management turnover. The main objective of this research is to develop an approach to analyze the spatial patterns of meteorological droughts based on annual precipitation data in Iran. By using a nonparametric spatial analysis neural network algorithm, the normalized and standardized precipitation data are classified into certain degrees of drought severity (extreme drought, severe drought, mild drought, and... 

In this paper with the use of fuzzy genetic algorithm combination with evolutionary algorithms, as a method for local searching, it has been tried to exploit high capabilities of genetic algorithm, as a search algorithm, beside to other evolutionary algorithms, as local search algorithms, in order to increase efficiency of a rule learning system. For this purpose three hybrid algorithms have been used for solving the intrusion detection problem. These three algorithms are combination of genetic algorithm and SFL and PSO as three evolutionary algorithms which try to introduce efficient solutions for complex optimization problems by patterning from natural treatments. © 2007 IEEE