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Jiang Z.,Huazhong University of Science and Technology | Sun P.,Beijing Engineering Corporation Ltd | Ji C.,North China Electrical Power University | Zhou J.,Huazhong University of Science and Technology
Journal of Hydrology | Year: 2015

The dynamic control operation of reservoir flood limited water level (FLWL) can solve the contradictions between reservoir flood control and beneficial operation well, and it is an important measure to make sure the security of flood control and realize the flood utilization. The dynamic control bound of FLWL is a fundamental key element for implementing reservoir dynamic control operation. In order to optimize the dynamic control bound of FLWL by considering flood forecasting error, this paper took the forecasting error as a fuzzy variable, and described it with the emerging credibility theory in recent years. By combining the flood forecasting error quantitative model, a credibility-based fuzzy chance constrained model used to optimize the dynamic control bound was proposed in this paper, and fuzzy simulation technology was used to solve the model. The FENGTAN reservoir in China was selected as a case study, and the results show that, compared with the original operation water level, the initial operation water level (IOWL) of FENGTAN reservoir can be raised 4. m, 2. m and 5.5. m respectively in the three division stages of flood season, and without increasing flood control risk. In addition, the rationality and feasibility of the proposed forecasting error quantitative model and credibility-based dynamic control bound optimization model are verified by the calculation results of extreme risk theory. © 2015 Elsevier B.V. Source

Chen Y.,China University of Petroleum - Beijing | Zhang J.,Beijing Engineering Corporation Ltd | Zhang H.,China University of Petroleum - Beijing | Zheng W.,China University of Petroleum - Beijing | Cao J.,China National Offshore Oil Corporation
Ship Building of China | Year: 2015

Based on power strain hardening assumption, analytical solutions of ultimate bending capacity of offshore pipeline are presented. Analytical solutions with elastic-perfectly plastic assumption are provided as well. The proposed methods are able to account for the combined actions of internal pressure, axial force and bending moment. Good agreement is observed when ultimate bending capacities obtained from analytical solutions are compared with experimental results. It is shown that strain hardening pipes yield higher bending capacity than that of pipe with elastic-perfectly plastic material, and the ignorance of strain hardening, as commonly assumed in current code, may underestimate the ultimate bending capacity of steel pipes. The solutions presented in this paper are applicable in the structural design and safety evaluation of offshore pipelines. ©, 2015, The Editorial Board of Ship Building of China. All right reserved. Source

Zhang X.,Beijing Engineering Corporation Ltd | Hou X.,Sinohydro Bureau 3. Co. | Qi J.,Beijing Engineering Corporation Ltd
Modern Tunnelling Technology | Year: 2014

There are 4 inclined shafts for the headrace system of pumped-storage power station in Hohhot with excavation angles of 55° and 60° and lengths of 340 ~ 398 m(including bend section). In guide shaft excavation, a combined method of raise boring and Alimak climber raising was adopted. Namely, the raise boring machine drills from top to bottom, while the raise climber works from bottom to top; after connection, the raise climber continues to work to form a mucking shaft. With this method, the maximum drilling depth reaches up to 180 m per month. And this paper introduced the excavation techniques of guide shaft from the aspects of scheme selection and implementation, technical problems and their treatments, etc, thus providing experiences for similar constructions. ©, 2015, Editorial Office of "Modern Tunnelling Technology". All right reserved. Source

Zhang C.,CAS Institute of Policy and Management | Dong L.,Beijing Engineering Corporation Ltd | Liu Y.,CAS Institute of Policy and Management | Qiao H.,National Research Institute for Rural Electrification
Sustainability (Switzerland) | Year: 2016

Water is an essential foundation for socio-economic development and environmental protection. As such, it is very critical for a city's sustainable development. This study analyzed the changes in water utilization structure and its impact factors using water consumption data for agricultural, industrial, domestic and ecological areas in the city of Tianjin, China from 2004 to 2013. On this base, the evolution law and impact factors of water utilization structure were depicted by information entropy and grey correlation respectively. These analyses lead to three main results. First, the total amount of water consumption in Tianjin increased slightly from 2004 to 2013. Second, the information entropy and equilibrium degree peaked in 2010. From 2004 to 2010, the water utilization structure tended to be more disordered and balanced. Third, the economic and social factors seemed to influence the water utilization structure, while the main impact factors were industrial structure, per capita green area, cultivated area, effective irrigation area, rural electricity consumption, animal husbandry output, resident population, per capita domestic water etc. © 2016 by the authors. Source

Zhao H.J.,Beijing Engineering Corporation Ltd | Jin Y.D.,Beijing Engineering Corporation Ltd | Chai F.X.,China Institute of Water Resources and Hydropower Research
Progress in Civil, Architectural and Hydraulic Engineering - Selected Papers of the 4th International Conference on Civil, Architectural and Hydraulic Engineering, ICCAHE 2015 | Year: 2016

The digital stream network and spatial information were extracted from raster-based DEM data. The grid-based distributed hydrological and silty model was developed on the basis of excess infiltration mechanism in the areas with high and coarse sediment yield, considering the impact of structural measures for soil conservation on runoff routing. The model was implemented in the Chabagou basin of the Wuding River that is a tributary of the Yellow River from the year 1970 to 1989. The results show that the developed distributed model is suitable for the small watershed in the loess area. © 2016 Taylor & Francis Group, London. Source

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