Water resources in arid and semi-arid regions are heavily influenced by climate change, water shortage, water regulations, and increased water demands. Monthly discharge is one of the most important factors in hydrological studies. Some of the basins are not equipped with adequate hydrometric equipment. In such a case, average monthly discharge could be estimated by regional monthly water balan...

nowadays, increasing of greenhouse gases emissionscussed by human activities is the main factor of climate change. global warming has also changed the frequency of extreme rainfall events in many areas. this research presents an analysis of how the change in the frequency of maximum daily rainfall under three emission scenarios in 2021-2040 periods in the khorasan-razavi province. the maximum d...

A brief analysis on the distribution range of some of the species dominating in the arid and extra arid regions of North Africa and Arabian Peninsula is presented. These species are belonging to three phytogeographical categories namely: Saharo-Sindian, Sudano-Deccanian and Tropical African-Indian elements. Species included for this study are either disjunct or they have a wider distribution, s...

We develop a machinery which translates results on algebraic sums of sets of reals into the corresponding results on their cartesian product. Some consequences are: (1) The product of meager/null-additive sets in the Cantor space is meager/nulladditive, respectively. (2) The product of a meager/null-additive set and a strong measure zero/strongly meager set in the Cantor space has strong measur...

A $*$-reduction between two equivalence relations is a Baire measurable reduction which preserves generic notions, i.e., preimages of meager sets are meager. We show that orbit induces generically an embedding the associated Becker graphs. introduce notion dimension for Polish $G$-spaces preserved under $*$-reductions. For every natural number $n$ we define free action $S_{\infty}$ whose on inv...

Classically it is known that any set with packing dimension less than 1 is meager in the sense of Baire category. We establish a resource-bounded extension: if a class X has ∆-strong dimension less than 1, then X is ∆-meager. This has the applications of explaining some of Lutz’s simultaneous ∆-meager, ∆-measure 0 results and providing a new proof of a Gu’s strong dimension result on infinitely...