shortage of water has been a great consideration since ancient times in iran. the yearly average atmospheric precipitation in iran is around 250 mm considering the total area of the country, it can be estimated that our share of water is 420 x 109 per year. due to evaporation and run off to the sea through rivers and infliction it has been estimated the available water can not be more than 120 ...

The objective of BASELINE is to publish short communications on different aspects of pollution of the marine environment. Only those papers which clearly identify the quality of the data will be considered for publication. Contributors to Baseline should refer to 'Baseline—The New Format and Content' (Mar. Effective metal concentrations in porewater and seawater labile metal concentrations asso...

soil unsaturated zone is one of the important parts of hydrological cycle that has an especial role in agricultural water resources management. the objective of this research was to determine the amount of root water uptake under simultaneous water, salinity, and nitrogen stresses as prevailing conditions in arid and semi-arid regions. to do so, the experiment was conducted with four quantitati...

A Generalized Temporal Role Based Access Control (GTRBAC) model that captures an exhaustive set of temporal constraint needs for access control has recently been proposed. GTRBAC’s language constructs allow one to specify various temporal constraints on role, userrole assignments and role-permission assignments. However, the presence of temporal constraints on role enablings and role activation...

RBAC model is renowned as a security model for corporate environment, since its components, especially role hierarchy, are suitable for modeling an organization structure. But the functional role hierarchy constructed through the existing role engineering approaches does not reflect an organization structure, because they do not take the structural characteristics of the organization into accou...