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The ecosystem model of surface water quality in the river basin was formalized on the basis of the theory of neural networks. The neural network is trained based on the observation data. Upon that the methods of environmental assessment and suitability of water for irrigation as well as for drinking needs can be used for the neural networking. The developed ecosystem model enables to improve significantly...
This paper presents a model of oil spill spread taking into account the evaporation of light, neutral and non-evaporating pseudofractions of oil spots, dissolution of oil spots and biodegradation. An approximation of the diffusion-convection problem is performed based on schemes of high order of accuracy. An experimental implementation, designed to model possible ecosystem scenarios of shallow waters...
The paper covers problems of solving tasks of water ecology on multiprocessor computer system (MCS). We proposed a new model of biological rehabilitation of shallow waters in view the factors that have a significant influence on the water quality. Its discretization was performed with using the balance method and the implicit scheme with central differences. The proposed numerical method for the solution...
This paper investigates the use of Artificial Neural Networks (ANN), more precisely Multi-Layer Perceptrons (MLP), as an alternative to the weighting function μ in a Multi-Model approach type Takagi Sugeno (TS) for an Activated Sludge Reactor. The reduced bio-reactor activated sludge ASM1 model, which describes the biological degradation of an activated sludge reactor, is designed based on several...
MODIS chlorophyll-a concentration (Chla) data were assimilated into a coupled hydrodynamic-biological model using an Optimal Interpolation method. Simulations were conducted using MODIS data covering Taihu Lake in May 2009, when algal blooms typically begin to occur. The results of the assimilation approach showed improvements in the estimation of Chla distributions in spatial coherency and temporal...
Shallow water simulation enables the study of problems such as dam break, river, canal and coastal hydrodynamics, as well as the transport of inert substances, such as pollutants, on a fluid. This article describes a GPU efficient and cost-effective CUDA implementation of a finite volume numerical scheme for solving pollutant transport problems in bidimensional domains. The fluid is modeled by 2D...
Aiming at the seriousness and harmfulness of nitrogen pollution, in order to protect water resources and human health, this paper outlines nitrogen transport and transformation process in the groundwater. Based on the analysis of the present research situation about nitrogen transport and transformation at home and abroad, the authors think that 0-level or first-order kinetics hasn't describe nitrogen...
Based on characteristics of lake eutrophication, total phosphorus (TP), total nitrogen (TN), chemical oxygen demand(CODMn), secchi disk depth (SD) and biomass (BIO) were chosen as evaluation indexes. Aiming at the problem being too complex for the present evaluation methods on lake eutrophication, a new method, improved set pair analysis model was used to solve the complicated non-linear relation...
There are a great many of solid refuse including mining abolish stone, wall rocks, tailings and so on. Which have polluted soil, water, air and ecological environment. Its comprehensive utilization has already caused the extensive attention. It is very necessary for the comprehensive utilization evaluation, which makes government decision more reasonable. In this paper, the tailing comprehensive utilization...
As a powerful global optimization approach, genetic algorithms (GA)can solve a variety of optimization problems in which the objective function is discontinuous, non-differentiable, or highly non-linear, to produce high convergence speed and vast search space. In this thesis, Genetic algorithm and BP algorithm can be combined to achieve complementary advantages in order to help solve the problem better...
The agricultural pollution of non-point sources is the main cause of the eutrophication of surface water environment in rural areas. The pollution loads of COD, TN and SS were estimated by investigating the non-point sources in the upper Zihe river basin. The results showed that the yearly pollution load of every pollutant of non-point sources was higher than that of point sources. In the normal year,...
Water quality maintenance is always a focus in a fishpond in order to achieve a high harvest and good scenery. A wetland fishpond in Yingdong Village on Chongming Island, Shanghai has been studied. Through a 2D modeling analysis it is found that the water diversion from the neighboring Yangtze River is feasible and effective. The diversion can be conducted once every 2 months to achieve the desirable...
Non-point source pollution is one of the major problems caused by agricultural activities especially from planting cultivation. This paper describes the application of the Soil and Water Assessment Tool (SWAT) model in agricultural non-point source pollution of the Laohahe River watershed, located in northeast China. This initial hydrologic modeling analysis will facilitate future applications of...
Marine water quality model is complicated because of its multi-parameter and multi-response characteristic. In this paper, a new method based on data-driven model (DDM) is developed to retrieve the value of model parameters for model calibration. All training data are calculated by numerical water quality model from results of multi-parameter matching design cases. The basic idea is to find out the...
Biosorption of organic pollutants, expressed as COD, by aerobic and anaerobic sludge was conducted to examine equilibrium and kinetic models. Freundlich and Langmuir models were mostly used for mathematical description of the biosorption equilibrium. Freundlich equation was more fit to describe the equilibrium of biosorption process in this study. Under the same experimental condition, biosorptive...
Water environmental pollution is a widely attended important problem. With the development of economy and improvement of living standard, the discharge quantity of city sewage, power plant cooling water, etc. is increasing gradually. Because the discharge process is concerned with jet behavior, so it is significant to study on flow behavior near discharge outlet of sewage treated building in the theory...
A ComGIS-based risk evaluation and warning system was developed to ensure the safety of water sources in lower reaches of the Yangtze River. The whole transaction of water sources protection including monitoring, risk evaluation and warning was covered by the system, and functions of online monitoring, water quality modeling, risk analysis and warning was developed and integrated on the same platform...
It is a multi-objective, multi-criteria, multi-level and high-dimensional comprehensive issue to assess groundwater resources and environment carrying capacity affected many factors. Projection pursuit (PP) technology was adopted to reduce dimension of the above non-linear and high-dimensional problem. Particle swarm optimization (PSO) algorithm was introduced to optimize projection index function,...
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