The providing of pure water for human needs and irrigation is one of the most important problems of many countries in hot climate. Moreover waste water is not purified at all or insufficiently. Purified waste water could be used by mankind e.g. for irrigation in order to establish a closed water...

Asymptotic expansions for large deviation probabilities are used to approximate the cumulative distribution functions of noncentral generalized chi-square distributions, preferably in the far tails. The basic idea of how to deal with the tail probabilities consists in first rewriting these...