background: despite their simplicity and the low-cost, the conventional non-contact uv systems have low efficiency in water disinfection. the purpose of this study was to examine the possibility of upgrading these systems by some modifications in order to maximize the water contact with the uv radiation and as a result a better disinfection.    methods: in this study, two enhanced models of non...

abstract in this study, evaluation of swap model in simulating crop yield, water and salt movement in soil were investigated in the wheat- fodder maize cultivated units. the research was conducted in the voshmgir network, golestan province. the crop yield, soil humidity and moisture data in different times of agriculture year of 2007-2008 were measured. the measured and simulated data were anal...

abstarct precise knowledge of all components of water balance is essential to optimize water use in irrigated agriculture. however, water balance components are difficult to measure in required time intervals because their measuring is time consuming and costly. unsaturated zone simulator models are useful tools for predicting the effects of agricultural management on crop water use and can be ...

background: one issue of concern in water supply is the quality of water. measuring the qualitative parameters of water is time-consuming and costly. predicting these parameters using various models leads to a reduction in related expenses and the presentation of overall and comprehensive statistics for water resource management. methods: the present study used an artificial neural network (ann...

shortage of water resources and increasing demand to consumption of this scarce resource, leads to somenoticeable limitations. on the other hand, population growth and consequently, increasing demand for water in aridand semi arid regions , needs production in exchange of little amount of water consumption. to approach thisobjective, an experiment in the complete randomized blocks carried out i...

many mathematical models have been applied and developed for simulation of water and solute transport in irrigated agriculture. using a model, it should be first calibrated and validated for different regions. swap is a field scale model that simulates water, solute and heat movement in the soil profile. in this study, the swap model was evaluated for two years (2001 and 2002) on wheat in a sem...

a novel approach to determine optimal sampling locations under parameter uncertainty in a water distribution system (wds) for the purpose of its hydraulic model calibration is presented. the problem is formulated as a multi-objective optimisation problem under calibration parameter uncertainty. the objectives are to maximise the calibrated model accuracy and to minimise the number of sampling d...

soil erosion results from an interaction of several parameters, which vary in space and time. awareness ofenvironmental changes and their impact on the intensity and spatial pattern of water erosion can effectively help inrecognition of erosional reactions versus the affecting factors. the aim of this paper is to describe the development ofa methodology based on present knowledge and available ...

this research was carried out on corn in the orzuiyeh region of kerman province over two consecutive seasons (2005-6 to 2007-8). the experiment was done as a split plot with a completely randomized block design and four replications. four levels of consumed water (60%, 80%, 100% water requirement, water use based on regional custom) and three varieties (404sc, 700sc, 704sc) were the main factor...

gaz-angubin is a sweet exudate naturally produced by an insect from the gavan-e-gaz-angubin plant. adsorption and desorption isotherms for a gaz-angubin sample were determined at 15° and 25°c over a range of relative humidity from 0 to 90% using a dynamic vapor sorption system. at different levels of relative humidity, changes in sample mass were continuously measured versus time and described ...