Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT

Fengcheng, China

Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT

Fengcheng, China
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Gao F.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT | Huang Q.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT
Shengtai Xuebao/ Acta Ecologica Sinica | Year: 2011

A watershed is not only a complete natural geographical unit, with a defined ecological and hydrological pattern, but is also an area with concentrated human activity. Because of these features, it is widely recognized as the optimal scale to analyze ecological environments. However, one of the problems that arise when analyzing data at the watershed scale is how to store and manage the necessarily large data sets, specifically through database design and implementation. In China, there has been a lack of database design and application for multi-source, multi-scale, cross-band environmental data. Theory of the integrative spatial and attribute data, the "3S"(geographic information system; remote sensing and global positioning system), a spatial data engine (SDE) and spatial data warehouse techniques were used to build a large environmental database to analyze the present situation and the future requirements of the Tarim River Basin. In this paper, several important issues are discussed including methods for seamless integration of multi-source data, database specification design, element coding design, spatial index design, characteristic display table design, and input with one key design, among others. Initially, the physical data layer and logical data layer are separated, followed by the vector data and the raster data, and data is fully integrated in a unified multi-scale space frame system for the crack problems after cross-band operation in the Tarim River Basin. Database specification design, particularly the database naming convention, is an important part of data design and storage. Based on the relevant principles, and standards, the names of six categories of data sources, metadata and index graph were standardized by English abbreviations to improve user access of the large database. Element coding design aims to provide a unified correspondence for data storage, query, and analysis. Element coding design standards can be established according to the scales of graphics data, which is the basis for information sharing. Spatial index design is a key determinant of the efficiency of database access. The use of ArcSDE to provide a spatial index of vector data and the construction of a multi-level pyramid structure for raster data can improve the efficiency of data search. The characteristic display table is based on a data dictionary and meta table, mainly for its system information display service. By constructing the characteristic display table, the corresponding code is only called by the system when it is needed, which greatly improves the efficiency of display and response. Input with one key is proposed to solve problems associated with ineffective data storage and complicated operations, and to promote the reliability of data storage. Collectively, the above steps help achieve seamless integration and unified management of multi-source, multi-type, and large scale eco-environmental data collected at the watershed scale, which can offer possible data support for dynamic monitoring of the environment. The theory and practical application of this study can be extended to other basins or other database types.


Wang Y.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT | Shao L.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT | Zhou X.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT
Shuili Fadian Xuebao/Journal of Hydroelectric Engineering | Year: 2012

This paper proposes an improved set pair analysis (SPA) method using malleability of original relation degree to solve the problem of subtle differentiation between uniform, different and reverse in standard SPA. A water quality evaluation model was developed with this method for evaluation of the excellent and inferior tendency degree of the samples in the corresponding rank. It introduces a discrepancy coefficient and an entropy method to optimize the index system and adopts a superstandard multiple method to determine the synthetic weight of index. Combined with a fuzzy method, it was applied to evaluation of the surface water quality in Shanxi province. A comparison of the SPA method with gray classification method, synthesis index method, fuzzy neural networks and projection pursuit method, shows that its evaluations are closer to the real situation. It is a better method for evaluation and decision-making of water environment and has good potential application. © right.


Zhang H.,Chang'an University | Wang Y.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT | Jiang X.,Yellow River Institute of Hydraulic Research
Shuili Fadian Xuebao/Journal of Hydroelectric Engineering | Year: 2011

The difficulty in quantifying the ecological target is a general scheduling problem in the field of reservoir ecological regulation, and the micro-ecological requirements for the macro-control of river are often hard to satisfy. In the paper, a flow restoration method is adopted to obtain the flow process that is needed for the restoration of river eco-hydrological system health, and by this method a model is developed for the integrated scheduling of cascade reservoirs on the Yellow River mainstream. Through controlling the flows at the Yellow River eco-sections, water allocation schemes under different ecological requirements in the present conditions are obtained by applying this model. The calculations show that the eco-flow control greatly increases the design probability of water supply in the lower reaches of Yellow River, while causing small changes in water stress index, power generation and ecological damage rate. In the future 2020, however, the eco-flow control only brings about some increases in water stress index and ecological damage rate, but nearly no improvement on water supply or power generation. Thus, we conclude that the indicators' responses to reservoir ecological regulation in the Yellow River basin was not significant at present, while after 2020 the regulation will play an important role in the ecological protection to this basin and nearly no role in the power generation of cascade reservoirs. In the future, ecological regulation may become a crucial technique in relieving the pressure of increasing ecological damage rate and a possible measure for protecting the ecosystems. To meet the ecological water demand along the Yellow River mainstream, however, greater difficulties remain, unless drawing water resources from other river basins. © Copyright.


Zhang X.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at Xaut | Zhang X.,Shaanxi Provincial Academy of Environmental Science | Yu G.Q.,Key Laboratory for Geo hazards in Loess Area of Ministry of Land and Resources | Li Z.B.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at Xaut | And 2 more authors.
Water Resources Management | Year: 2014

The relationships between precipitation, vegetation and erosion are important yet unresolved issues in the field of earth surface processes. Vegetation plays an important role in controlling soil erosion. Through field simulated rainfall experiments, we analyzed the characteristics, regulation of, and correlation among the slope rainfall-infiltration-runoff, erosion and sediment under different vegetation types. The results showed that the forest effectively improved soil structure, had stronger runoff and sediment regulation and was influenced less by rainfall intensity than those under other vegetative conditions. In addition, the efficiency and pattern of the regulation of runoff and sediment varied with vegetation types as did the mechanism of action. The soil and water conservation function of forest was water storage and sediment reduction by plant root systems to reduce erosion power, increase infiltration, decrease runoff and reduce flow speed. The function of grassland was direct sediment interception based on surface vegetation canopy for runoff and sediment regulation. The root contribution to runoff and sediment reduction was relatively greater than the shoot contribution under forest conditions, whereas, the effect of shoots and roots on soil loss was almost equivalent under grassland conditions. The different spatial structures of vegetation affected runoff and sediment regulation in different ways, and plant root systems were crucial for soil and water conservation. The cumulative sediment yield of the slopes increased as a statistically significant power function of cumulative runoff. The coefficient and curve shape of function were dependent on vegetation type, soil properties, rainfall intensity and surface roughness. The process of slope runoff and sediment was divided into development, active and stable stages. These stages correlated with each other to constitute a complete rainfall-runoff and erosion-sediment process, which exhibited their own features at each stage. This study furthers understanding of the relationships between vegetation, soil erosion and precipitation. © 2014 Springer Science+Business Media Dordrecht.


Wu H.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT | Huang Q.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT | Xi S.,Sun Yat Sen University
Shuili Fadian Xuebao/Journal of Hydroelectric Engineering | Year: 2015

This paper applies a variable fuzzy set method based on entropy weight to construction of a framework of classified real-time flood forecasting using the concepts of clustering and classification. Fuzzy clustering was used to classify historical floods based on the flood antecedent impact factors and time-varying rainfall information. In the present study, this conceptual hydrological model was calibrated for each type of flood. In application, a fuzzy diagnosis model was used to identify the types of floods in future by using the flood information obtained. Results show that the classified framework gives a fast and accurate diagnosis of the type of flood and significantly improves the accuracy of flood forecasting. © Copyright.


Chen T.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT | Chen T.,Shanxi Company of Real Estate Service | Xie J.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT | Zhang G.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT | He W.,China Communications Construction Company Ltd.
Shuili Fadian Xuebao/Journal of Hydroelectric Engineering | Year: 2012

This paper purposes a dynamic parameter estimation method of Muskingum routing model for real-time flood forecasting based on BP artificial neural network to overcome the low accuracy problem of averaging and grading method in parameter calibration. In this new method, first flood characteristics are analyzed to obtain BP inputs and then an optimization algorithm is used for calibration of model parameters, i.e. BP outputs that are used for neutral network training. Application of this calibrated BP model to real-time flood forecast shows that the model is simple and more accurate. © right.


Xiao G.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT | Xie J.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT | Luo J.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT
Shuili Fadian Xuebao/Journal of Hydroelectric Engineering | Year: 2012

To provide more information support to decision making, this paper puts forward an improved NSGAII algorithm for multi-objectives reservoir flood dispatching (RFC-I-NSGAII), using the framework of evolutionary multi-objective optimization algorithm NSGAII. In this algorithm, coding based on discharging flow is adopted and a novel inver-over mutation operator is designed for reservoir flood dispatching. Simulation tests indicate that it can produce a set of Pareto optimal scheduling schemes with faster convergence and wider distrib ution, realizing the flood peak reducing goal. The efficiency of this operator, a contributor to acceleration and improvement on solution efficiency, was verified by the experiment. © right.


Zhang G.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT | Xie J.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT | Luo J.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT
Shuili Fadian Xuebao/Journal of Hydroelectric Engineering | Year: 2011

An immune clonal selection algorithm (ICSA) is described and analyzed and it is used to calibrate the ideal hydrological data generated by a hydrological model of Xin'anjiang hydropower. To calibrate the model parameters, four algorithms are examined and compared, shuffled complex evaluation algorithm (SCE-UA), parallel genetic algorithm (PGA), and parallel-swarms shuffling evolution algorithm (SMSE-PSO) and immune clonal selection algorithm (ICSA). The results show higher efficiency and accuracy of ICSA, and its application to analysis of practical data satisfies the design requirements. ICSA is a more effective method for calibrating hydrologic model. © Copyright.


Wan F.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT | Yuan W.,Zhengzhou University | Huang Q.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT | Chang J.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT
Shuili Fadian Xuebao/Journal of Hydroelectric Engineering | Year: 2010

Optimal operation of a complex cascade reservoirs system, mathematically high dimensional, often encounters dimension disaster and is trapped into a local optimum. This paper suggests a method of particle swarm optimization that is solved by the immune evolutionary algorithm. The algorithm combines the abilities of global searching of immune evolution with local searching of particle swarm, and hence avoids dependence on initial population and local trapping. A test case shows this new algorithm superior to progressive optimization.


Chang J.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT | Wang Y.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT | Huang Q.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT | Sun X.,Key Laboratory of Northwest Water Resources and Environment Ecology of MOE at XAUT
Shuili Fadian Xuebao/Journal of Hydroelectric Engineering | Year: 2014

The output of windpower plant is random, discontinuous and uncontrolled, so it is difficult to be absorbed by power network. Hydropower is advantageous in response rapid and adjustable; the disadvantage of windpower can be made up by compensation operation of hydropower plant and windpower plant. Based on analysis of the principle of compensation operation, this paper first demonstrates some objective and rules for such compensation, namely, output-electricity balance rule, and abandoned-water minimization rule. Then we present calculation methods for different conditions by using these rules and complementation calculations for joint operation of hydropower and windpower plants of the Northwest Grid in 2015. This work would provide a theoretical basis and practical approach to compensation operation of power plants. © Copyright.

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