runoff simulation is a vital issue in water resource planning and management. various models with different levels of accuracy and precision are developed for this purpose considering various prediction time scales. in this paper, two models of ihacres (identification of unit hydrographs and component flows from rainfall, evaporation and streamflow data) and ann (artificial neural network) mode...

[1] A technique to estimate the uncertainties of the parameters of a neural network model, i.e., the synaptic weights, was described in the work of Aires [2004]. Using these weight uncertainty estimates, we compute the uncertainties in the network outputs (i.e., error bars and correlation structure of these errors). Such quantities are very important for evaluating any application of the neural...

Long-term surveillance of aquatic environments is a costly endeavor, thus a sound strategy is necessary to select the locations of monitoring stations to improve the quality of a monitoring system. This can be accomplished by optimizing the locations of a sensor network with respect to the hydraulic and fate and transport characteristics of the surface water system. It is expected that such an ...

batiaghata upazila, khulna district in south-west coastal region of bangladesh is the mostly saline affected area, where agriculture activities are mainly dependent on rainfall. 23 water samples from surface water and shallow tube well (stw) were collected in the monsoon season and analyzed for physico-chemical properties to classify them according to salinity hazard. electrical conductivity (e...

We assessed the total nitrogen (N) concentrations of 28 still surface water (lake and pond), and 42 flowing surface water (river), monitoring sites under 29 typical terrestrial ecosystems of the Chinese Ecosystem Research Network (CERN) using monitoring data collected between 2004 and 2009. The results showed that the median total N concentrations of still surface water were significantly highe...

The unique structure and dynamics of the water hydrogen (H)-bond network enable a multitude of structures and chemical reactions in both bulk solutions and at interfaces. The underlying molecular interactions between water and dissolved electrolytes, organic molecules, and nanoscale interfaces are difficult to study and hence not fully understood, especially when it involves interactions of len...

introduction: given its low and sparse precipitation both in spatial and temporal scales, iran is nestled in an arid and semiarid part of the world. on the other hand, because of population growth, urbanization and the development of agriculture and industry sector is frequently encountered with increasing water demand. the increasing trend of water demand will widen the gap between water suppl...

a new sorbent composed of 3-aminopropyltriethoxy-silane-coated magnetic nanoparticles, functionalized with rhodium(iii) porphyrin complex was synthesized and characterized by elemental analysis, x-ray diffraction (xrd), transmission electron microscopy (tem), fourier transform infrared spectroscopy (ft-ir) and thermogravimetric analysis (tga). the effect of some co-existing anions present in aq...

the relative impacts of different types of land use on the surface water quality are yet to be ascertained and quantified. in this paper, the influence of different types of land use on surface water quality is investigated. rain events samples from different land use in the central plateau, iran, were analyzed for major ions. statistical analyses were employed to examine the statistical relati...

the world is facing severe challenges in meeting the rapidly growing demand for water resources. in addition,irrigation water which is the largest use of water in most developing countries and arid and semi arid regions, will likelyhave to be diverted increasingly to meet the needs of the households in urban areas and industry sectors whilst remaining aprime engine of agricultural growth. a lin...