Applied Mechanics and Materials Vols. 405-408

Abstract: JiYin hydraulic project is located at the branch of Keliya River, Yutian county of Xinjiang. During the stage of its planning and design, a magnitude 7.3 earthquake occurred 43km away from the southeast of the dam. As the earthquake was in the southeastern part of Altyn Tagh Fault which was recognized in the past as a low seismicity segment, the cognition about seismic surroundings had changed totally. Based on comparison between the two seismic safety evaluations on JiYin before and after the earthquake, epistemic uncertainties in probabilistic seismic hazard assessments have a significant effect on final results. Therefore, in order to mitigate earthquake disasters of dams, combination of probabilistic and deterministic methods should be applied for evaluating seismic hazards when large dams are constructed in strong seismicity regions.

Abstract: To solve the contradiction between Three Gorges reservoir impounding and downstream drought resistance in flood recession period, impounding in advance scheme is studied in this paper. Firstly, an improved impounding mode by strictly satisfying the downstream drought resistance discharge constraints is proposed. Then, by comparing from the aspects of annual average fill storage rate, final water level, power generation, surplus water and flood risk of different impounding time schemes, the optimum improved impounding scheme is determined and validated by typical year 1996. The study can proved scientific guidance for drought control of Three Gorges reservoir.

Abstract: The decision support system (DSS) developed to support the management of the water resource system of Ningxia are presented. The DSS includes information component system that performs data acquisition, management and visualization. In GIS module, Google Earth and ArcGIS are integrated, through KML (KMZ) files for data exchange, provides integrated services and decision support for the management of water resources. Model component performs simulation and optimization of the water resources. The models, which are the focus of the present work, reorganized into two main parts. The first one is water demand forecast model, which, based on the analysis of historical hydrological data, generates forecasts of the water demand amount. The second one allows the detailed study of the water resources implementing the optimization methodology. The mathematical method performs the allocation of the water resources to the different system components, keeping the number of control variables small, even for complex water resources like the one under study. The DSS is now in the final stage of its development and its results, some of which are summarized in the paper, have been utilized to support the water resources management. This template explains and demonstrates how to prepare your camera-ready paper for Trans Tech Publications. The best is to read these instructions and follow the outline of this text.

Abstract: Climate is an important factor which formed and affected surface water resources. Through sensitivity analysis of natural runoff towards climate change, assuming the main factors effect runoff are precipitation and temperature, then according to the possible tendency of climate changes in the future, set climate scenarios, and use the hydrological model simulate the changes trend of runoff under different climate scenarios, thereby analyze the climate change impacts on surface water resources. The results show that annual runoff will be increased with the increasing annual precipitation, and it will be reduced with rise of annual temperature, the sensitivity that annual runoff towards the change of precipitation and temperature are equally notable, both of them are two major factors impact on the change of runoff and the precipitation change impacts on annual runoff will be even more obvious in flood season. Last, with the global warming trend, put forward the corresponding adaptive measures of energy conservation and emissions reduction。

Abstract: Based on the hydro-geological survey, sampling analysis and combined with ground water flow systems theory, the work studied coal gangue leachate of a typical sandy base coal waste field in Erdos on ground water environmental impact. The results showed that pile of coal waste change the original characteristics of ground water flow systems, coal waste field from ground water discharge areas change into the runoff area, the bottom of Gangue heap immersion in ground water long term, the toxic and hazardous substances released and spread to the downstream by ground water runoff. Chromium, arsenic, fluoride, sulfateradical, copper, zinc, nickel, manganese and other pollution factors in the downstream ground water of gangue field and surface outlet is much higher than background value, where concentration of arsenic and NO_3–N is 1.013mg / l and 31.2 mg / l, respectively higher than the background value which is 148 and 3 times.

Abstract: Based on site investigation data and historical data of characteristic hydrological years in Tigris River, the natural conditions and sediment environment were analyzed, a 2D mathematical model of flow and sediment was used to analyzed the intake schemes in Wassit power station (4×330MW). The calculation results based on the data of flow and sediment in representative year show that the erosion and deposition will occur in the region of water intake engineering. So the reasonable design parameters related to water intake by pump vessel should be provided by designer.

Abstract: The hydrological processes are becoming more and more complex. Fractal dimension is one of the important measurements of complexity. This paper utilizes wavelets transform technique to calculate the fractal dimension of runoff for eight stations (Zhimenda, Shigu, Ganzi, Yajiang, Guili, Luning, Xiaodeshi, Pingshan ) in the Jinsha River Basin. The results show: the runoff series in the Jinsha River Basin is fractal; the approach for estimating the fractal dimension by using wavelet transform coefficients is feasible and effective; the fractal dimension of runoff reflect the influence of factors on the runoff.

Abstract: The Particle Swarm Optimization (PSO) method was used to calibrate the Xinanjiang (XAJ) conceptual rainfall-runoff flood forecasting model, using a 7-year record of historical data of Yandu river watershed. Based on results of calibration runs using different objective functions, it is concluded that parameters optimization has a certain relationship with the choice of objective functions and the results vary with different functions. The simulation and prediction results were reasonable, as PSO method was used in XAJ model with observed data of Yandu river, combined with layer-debugging theory of Zhao Ren-jun.

Abstract: Based on the MIKE21 software, the water quality model to simulate flow field, velocity, and proliferation of pollutants before and after ecological islands is established in Wohushan Reservoir. It consists of mass equations and momentum equations. The results indicate ecological islands can ease the phenomenon of reservoir circulation and speed up the water exchange rate in the vertical direction that shortens the recovery time of water. The study provides a strong guarantee for water resources regulation, management and protection of Wohushan Reservoir.

Abstract: The optimal selection of irrigation systems is a complex process that contains lots of uncertainty factors, such as the influence of natural resources, technical level, the environment, economic and society conditions. With analyzing the present water resources utilization of Ordos City and considering the available research achievement of water-saving irrigation, this paper select technology, resources, environment, economy, society as the primary indexes that contains its 28 subordinate secondary indexes, establish irrigation systems optimization model, then determine the appropriate value of decision under the effects of different indexes and establish a corresponding knowledge matrix. In the last, DS combination rule is used to calculate the optimal value of different knowledge matrixs basic probability assignment, and the research results shows that the optimal value of Ordos city from high to low in turn are reeling sprinkler irrigation, large clockwise sprinkler irrigation, mobile sprinkler irrigation, low pressure pipe irrigation.