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    15 December 2018, Issue 12
      
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  • China Rural Water and Hydropower. 2018, (12):  1-7. 
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    In order to explore the quantitative effects of salinity and nitrogen application on photosynthetic characteristics and dry matter accumulation (DMA) of crops, field experiments of sunflower were carried out under different soil salinity and nitrogen application in this study. The two estimation models using Gaussian integration (GIM) and population photosynthetic integration methods (PPIM) respectively for sunflower DM production were established, the accuracy of the two models were analyzed and evaluated using experimental measured values. The results showed: (1) Soil salinity inhibited the net photosynthetic rate (Pn) and stomatal conductance (Gs) of sunflower, while adding nitrogen fertilizer to some extent alleviated the stress on Pn and Gs; (2) The DM production of sunflower was gradually decreased with the soil salinity increase, although DM production increased with the nitrogen application increase, compared with N1(180 kg/hm2) treatment, the DMA was increased by 4.7%, 12.6% and 20.1% of three salinity levels under N2(270 kg/hm2); (3) The estimation accuracy of DM production models decreases with the soil salinity increase; (4) Compared with the GIM model, the PPIM model has a higher simulation precision to estimate DM production of sunflower in salinity farmland (RRMSEGIM>RRMSEPPIM), which could provide a reference for crop growth simulation, irrigation and fertilization management in salinity area.
  • China Rural Water and Hydropower. 2018, (12):  25-28. 
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    Aiming at the problem of large irrigation quota in some orchard in Shanxi, the orchard located in the Jiamakou Irrigation District was taken as the research object. Based on close-end border scale, topographic conditions and actual irrigation situation of the orchard, irrigation technical parameters including close-end border length and discharge per unit width were optimized in conditions of intense infiltration, less intense infiltration and moderate infiltration by using flow simulation technology and parameter optimization model of surface irrigation. The optimized irrigation technical parameters of border irrigation of three types of soil infiltration were obtained. The results could provide reference for the convenience of users.
  • China Rural Water and Hydropower. 2018, (12):  41-44. 
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    Water-saving irrigation is an effective way to solve the contradictions of the "water and field" in our country. The vast but there was a terrible shortage of water resources of western region, in order to improve the effective utilization of water resources, the construction of a large number of water-saving irrigation projects, but the post - evaluation work has not been carried out in a timely and effective way to find out the shortcomings of the irrigation projects and make an improvement. Taking the irrigation projects of Fenyang city, Shanxi Province from 2005 to 2013 as an example, conduct post-evaluation in accordance with national standards and norms. The grey relational degree method was used for post-evaluation on the basis of improving the post-evaluation index system and evaluation content. And the results pointed that in the system layer, the correlation degree of the construction implementation evaluation is the largest, followed by the effect evaluation. The correlation degree of the target evaluation and social impact assessment is relatively small, and the degree of reaching the expected target is not ideal, which needs to be further improved. And then, in the target layer, the correlation degree of process evaluation is the largest, which indicates that the process evaluation result of the project is better, and the reality is the closest to the expected target. The comprehensive evaluation has the smallest correlation degree, which indicates that the actual situation is far from the expected target and needs further improvement. In the index layer, the completion status of the index can be determined by the correlation coefficient, and then targeted improvement can be made, and scientific basis can be provided for the projects under construction and planned construction. At last, for this project, the overall evaluation result is good, but the project operation condition needs to be further improved.
  • China Rural Water and Hydropower. 2018, (12):  50-53. 
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    Take Qiangwei river in Yancheng city as the research object, based on factor analysis and optimized nonlinear grey Bernoulli model, combined with the water quality data from 2009 to 2017, the paper analysizes the water quality improvement and the governance effect of the main pollution factor of comprehensive treatment of black and smelly water. Results show that the implementation of comprehensive treatment of black and smelly water makes Qiangwei river water quality improved obviously, the life pollution and nutrient pollution control effect is obvious. But inorganic pollution and water physical environment improvement effect is not obvious, so further formulation and implementation of corresponding measures is needed.The results also provide reference and basis to plan the objectives and tasks in next phase of comprehensive treatment of black and smelly water.
  • China Rural Water and Hydropower. 2018, (12):  59-65. 
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    The channel-type reservoirs in southwest mountain areas have different characteristics from those in the plain areas, and they have both dual-morphological characteristics of rivers and lakes. Because of the deep water and low water temperature of the reservoir, seasonal stratification of the reservoir can cause changes in the physical, chemical, and biological processes of the reservoir. This paper the Zipingpu Reservoir, a typical river-type reservoir in the southwestern mountainous area as an example. Time cluster analysis was conducted on the monitoring data of the 12 cross-sections of the Zipingpu Reservoir from 2016 to 2017, with the characteristics of seasonal changes. The results showed that: ①Water quality showed two phases of change due to the seasonal changes: May to September was the river morphology phases, and January to April and October to December was lake morphology phases. ②Through principal component analysis and multiple linear regression analysis, it was found that the nutritional status of water bodies was influenced by different principal components in different phases. The water quality of lake morphology phases was mainly influenced by water pollution and phosphorus, followed by agricultural nutrient substances and biochemical factors. The water quality of river morphology phases was mainly influenced by biochemical factors and human activities, followed by organic matter. ③The correlation between water quality factors was simplified through principal component analysis and it was found that Chla was significantly related to each factor, and the main factors such as turbidity, TP and other morphological phases were closely related to the concentration distribution of Chla. The research in different phases of reservoirs can avoid the inaccuracy caused by the correlation between the water quality indexes during a single hydrological period, make the analysis of water quality more comprehensive. And it also make certain research significance to reflect the nutritional status of river-type reservoirs in southwest mountainous areas.
  • China Rural Water and Hydropower. 2018, (12):  70-76. 
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    It is essential for social and economic development to protect urban water sources. At present,the research on water source protection mainly focuses on two aspects:quality of water environment and quantity of water resource. From the aspect of water conservation capacity,this paper takes Songhuaba water source area as the typical area,and studies the influence of soil layers in various land use types on that capacity. Meanwhile,aiming to get the changing process of the indexes from various land use types,such as soil bulk density,natural water content, saturated water content, effective water conservation amount, water conserving precipitation,capillary porosity,non capillary porosity,total porosity, capillary storage,non capillary storage,total phosphorus content, total potassium content and organic matter content,etc. On this basis,quantitative analysis and comprehensive evaluation of water conservation capacity of soil layers in various land use types should take place to provide scientific basis for the formulation of water resource protecting strategy in water source area from the aspect of water conservation.
  • China Rural Water and Hydropower. 2018, (12):  82-86. 
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    The optimum adsorption conditions of F-removal by Mg/Al/Fe hydrotalcite (MLT) were studied. The Plackett-Burman experiment was used to select the main affecting factors of the F-removal rate. The Box-Behnken experiment in response surface method was used to optimize the design and get a regression model. The optimum adsorption conditions obtained from the model are as follows: calcination temperature 542.22°C, MLT dosage 17.11g/L, reaction time 235.11min. Under the conditions, F-removal rate is 99.39%, which was only 0.14% different from the predicted value, indicating the practicality of the model. Using MLT to treat actual groundwater, the treated F-concentration can meet Class III requirements of the groundwater quality standard, indicating that the hydrotalcite-like compound has good application value, and the MLT adsorption process conforms to the pseudo-second-order kinetics.
  • China Rural Water and Hydropower. 2018, (12):  87-89. 
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    The construction of water culture and wisdom community is a systematic project that requires universal participation. Under the background of the era of big data, water culture construction is facing new problems and severe situation. It is urgent to absorb and draw on modern science and technology to explore more effective innovation management system. The rise of the intelligent community provides a new perspective for the solution of this problem. At the same time, it also improves the efficiency of water culture and broadens the way of water culture communication. Therefore, starting from the definition of the water culture intelligent community, we can grasp the management system of the water culture Intelligent Community and explore the corresponding innovative implementation path.
  • China Rural Water and Hydropower. 2018, (12):  90-93. 
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    As an important branch of machine learning, deep learning shows bright eyes in image processing and speech recognition and has good prospects in the water conservancy industry. This article elaborated the development history of deep learning and introduced three algorithms that are used in deep learning: convolutional neural networks, deep confidence networks, and stacked automatic encoders, combined with the current application of deep learning in the water conservancy industry. Remote Sensing Image Classification, Water Quality Analysis and Hydrological Forecast Finally, the paper analyzes the problems and future trends of the application of deep learning in the water conservancy industry
  • China Rural Water and Hydropower. 2018, (12):  94-100. 
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    The east branch of Huangbai river basin is an important water source in yichang city, it is of great importance to accurately simulate the runoff process for water resource management. In this study, the distributed Soil and Water Assessment Tool (SWAT) model was used for monthly runoff simulation in the east branch of Huangbai river basin. Paramter sensitivity, calibration and uncertainty analysis was conducted with the observed data from 2008 to 2016 by SUFU-2 algorithm in SWAT-CUP. The sensitivity results showed that the selected 19 parameters have different influences on the simulated runoff process, among which CN2, ESCO and SOL_K are the most sensitive. Monthy calibration and validation results demonstrated good model performances. The Nash-Sutcliffe efficiency coefficient (NSE)、ratio of root mean square error to standard deviation (RSR) and percent bias (PBIAS) of all sites are within the error range.The uncertainty analysis shows that of all stations are greater 0.6 while is less than 1. Most of the observations fall within 95PPU, indicating the uncertainty of the model is small. In general,the SWAT model has good applicability in the study area, with high accuracy and small uncertainty, which can accurately simulate the runoff process
  • China Rural Water and Hydropower. 2018, (12):  101-105. 
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    In order to understand the overall status and development trend of water resources carrying capacity, the evaluation index system of water resources carrying capacity was constructed by taking Yancheng city as an example. Improved TOPSIS method was combined with the combined weighting method to evaluate water resources carrying capacity of Yancheng, and the main influencing factors were identified by the obstacle factor diagnostic model. The results show that the water resources carrying capacity of Yancheng has shown a trend of improvement from level 4 in 2005 to level 2 in 2020; from 2005 to 2020, the impact of the water resources subsystem on water resources carrying capacity in Yancheng City has been continuously increasing while the social and economic subsystems have shown the opposite trend,and the impact of the ecological and environmental subsystem on the water resources carrying capacity has changed little; according to the calculation, the obstacle degrees of per capita water resources, ratio of groundwater overdraft area, and urban green coverage ratio have been increasing, while the obstacle degrees of the indicators related to water use efficiency have been the opposite, and the obstacle degree of water quality compliance rate in water functional areas has shown a tendency to fluctuate. The evaluation results and methods are reliable and can be used as a reference for evaluation of water resources carrying capacity of other cities.
  • China Rural Water and Hydropower. 2018, (12):  106-109. 
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    Based on the daily temperature data from three stations in or around the Wushui River basin during 1958~2014, variations of the extreme temperature were analyzed in this study in using of statistical analysis methods. The result shows that: ①annual mean maximal and minimum temperature were ascending notably during the past 57 years, with the climate tendency of 0.08℃/10a and 0.19℃/10a.②Spring mean maximal temperatures rose the most significantly with the climate tendency of 0.16℃/10a, autumn and winter mean minimum temperature rose the most significantly with the climate tendency of 0.23℃/10a.③ The positive anomaly of annual mean maximal minimum temperature happen in the late 1990s. ④ Number of the frost day and old nights reduced significantly, while the warm night increased significantly. These three extreme temperature indexes changed dramatically since middle1980s.
  • China Rural Water and Hydropower. 2018, (12):  126-128. 
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    Guhai pumping station project is located in the Yellow River shelter-forest, there are some serious problems in the body and cover of the pump due to the influence of sediment wear, such as the pump body is serious perforated, tongue gap is smooth, flow geometry size is changed, and water leakage in high and low pressure area of water pump. These have seriously affected the operation efficiency of the pump station, increased the maintenance cost of electromechanical equipment and the workload of maintenance, and have long troubled the efficient, safe and economic operation of the project. The polyurethane composite resin mortar coating technology is developed by Yellow River Institute of Hydraulic Research, which the amino materials is used as curing agent to improve the peel strength and decrease the brittleness of epoxy resin, and the polyurethane composite resin mortar abrasion resistant coatings are formed by use of polyurethane materials strong resistance to cavitation performance. The technology is widely used in Changshantou pumping station pumps in the pump casing abrasion repair, the coating effect is obvious after a year to run, the operation of the pump efficiency is stable for a long time, which provides reference for water pump station and pump manufacturer to solve the cavitation problem of water pump case.
  • China Rural Water and Hydropower. 2018, (12):  134-137. 
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    In order to study the pressure pulsation law and the distribution law of the flow induced noise in the reverse power generation of the mixed flow pump, the three-dimensional numerical simulation of the full flow passage of the mixed flow pump is carried out. The maximum pressure fluctuation amplitude at the outlet of the runner is about 1.3 times that of the inlet of the runner, about 3 times the inlet of the guide blade, and the amplitude of the pressure pulsation from the hub to the wheel. The margin gradually diminished. The main frequency of the pressure pulsation at the inlet of the guide vane is the rotation frequency, and the main frequency of the pressure pulsation at the inlet of the runner is the blade frequency. The boundary element method is used to study the sound field of the mixed flow pump in normal power generation. The noise generated by the runner area and the guide leaf area is mainly discrete noise, and the maximum sound pressure level can reach 120dB. Because the solid structure of the mixed flow pump resonances with the water flow, the main frequency of the pressure pulsation is not consistent with the main frequency of the flow induced noise, which makes the sound pressure level of the three order leaf frequency of the noise increase, about 1.1 times that of the blade passing through the frequency sound pressure level.
  • China Rural Water and Hydropower. 2018, (12):  138-142. 
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    In order to solve the problem of large computational complexity and low efficiency caused by the optimization of the optimization algorithm and the finite element analysis, the non-overflow dam section of a concrete gravity dam is taken as the analysis object, and the Kriging model of safety factor and maximum width of cross-section and cross-sectional area of the dam are respectively constructed; combined with genetic algorithm, the dam body is optimized with the minimum cross-sectional area of the dam as the optimization target. On this basis, the functional gradient materials idea is applied to partition the optimal section material, which makes the stress distribution of key parts of the dam more reasonable. The results show that: 1) The calculation accuracy of the Kriging model satisfies the engineering design requirements, and the optimization algorithm based on the Kriging model greatly shortens the optimization time compared with the original algorithm; 2) the area of the dam body after optimization is reduced by 14.02%; 3) the dam heel is made of 14GPa concrete with the dam toe 25.5GPa and the elastic modulus gradient is not more than 11.5GPa which is beneficial to the stress distribution of the dam and has certain engineering application value.
  • QIU BingKun
    China Rural Water and Hydropower. 2018, (12):  143-148. 
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    In combination with the engineering practice of a pumped storage hydropower station, a finite element model of the underground powerhouse structure including surrounding rock was established in this paper. Introducing viscous-spring artificial boundary, the seismic responses under artificial waves and Koyna waves of the underground powerhouse structure are analyzed using the time history method. The results show that, the acceleration and displacement response under earthquake of underground powerhouse structure increase with the increase of elevation. However, the response of the mass concrete structure below the turbine floor is small with the change of elevation, and the response of the beam-column structure above the turbine floor is more obvious with the increase of elevation. The peak values of acceleration and displacement responses of the powerhouse structure are generally found in floors, holes, wall pillars, etc. Meanwhile, there are obvious stress concentrations in some local positions such as floor holes, staircase holes, and slab-column junctions. In addition, structural responses and seismic weaknesses presented under artificial waves and natural waves are basically the same. The difference in spectral characteristics between seismic waves causes the difference in response peak values. Thus, it is necessary to use multiple waves to study the seismic response of the structure.
  • China Rural Water and Hydropower. 2018, (12):  149-155. 
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    Take typical widened levee for example, taking clay and arenosol serve as materials of old levee body and widing body, the paper used numerical analysis software to calculate the seepage and deformation characteristics of widened levee under water level. The results show that the water content contour line is discontinuous at the intersection of the old and new levee body, the total water head contour line is rejected by the interface, and the water content and the total head appear sharply lower. Seepage slope significantly changed at the interface and widened subgrade toe. The change rate of water content, total water head and hydraulic gradient increase with height of subgrade. The maximum settlement of the widened levee appears at the shoulder of the new levee, and the settlement is related to the height of the water level. The vertical deformation of the levee foundation is saddle shaped. The lateral deformation of the widened levee shows the trend of the old and the new levee moving outwards.The change of the seepage field is caused by the difference of the new and old filling properties of the subgrade under the seepage action of river water. Deformation is caused by the influence of seepage field on the stress field under the effect of new levee self weight.
  • China Rural Water and Hydropower. 2018, (12):  156-160. 
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    With the improvement of construction technology for water conveyance projects, catenary-shaped sections have been more and more widely used. However, for the calculation of the normal depth of the catenary-shaped section, there is an analytical solution to the normal depth of the design flow, and the solution to the calculation of the normal depth of the non-design flow is beyond the equation and theoretically cannot be directly solved. Firstly, according to the geometrical characteristics of the catenary-shaped section, the hydraulic elements and the basic equations of normal depth, the analytical solution formula for the normal depth of the design flow is obtained. Second, by introducing appropriate dimensionless parameters, the implicit function equations for the normal depth of the catenary channel are derived. After the mathematical transformation, an iterative calculation formula of normal depth is obtained, and at the same time, the formula for calculating the initial value of normal depth is given, and the initial value function is brought into the iterative calculation formula to obtain a direct calculation formula for the normal depth of non-design flow. Finally, the error analysis and comparison of the formulas show that the absolute value of the maximum relative error of the initial value calculation formula is less than 0.054% within the applicable range of the project, and the absolute value of the maximum relative error of the direct calculation formula is less than 0.0083%. Far more than the accuracy of existing calculation formulas.
  • China Rural Water and Hydropower. 2018, (12):  161-164. 
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    In the area with large temperature difference, the temperature control of the RCC gravity dam during construction period is extremely difficult, which is a key concern in construction. The temperature field and stress field during the construction period of RCC dams is simulated fully by using the methods of “negatively hypothermal heat method” and “volume force method” in the paper. The discipline of Dam cracking is revealed by fluctuating the key parameters of temperature control measures, such as concrete pouring temperature and the temperature of cooling water pipe. And the Lagrange Method is used to find the best solution. The achievement have been applied to the construction of the Yunnan Lead Plant Dam and plays the important role in crack control, which can provides theoretical and technical reference for temperature control and crack prevention for RCC Gravity Dam in the area with large temperature difference.
  • China Rural Water and Hydropower. 2018, (12):  165-168. 
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    The existing construction equipment of cast-in-place covered pipelines is suitable for the casting of small diameter pipes, which cannot meet the construction needs of large diameter covered pipelines needed for irrigation canals and ditches. For the construction requirements of large diameter cast-in-place covered pipelines, the traction sliding mold large diameter construction equipment of covered pipelines and the self-propelled sliding mold large diameter construction equipment of covered pipelines improved on it have been developed, and a comparative analysis of technical and economic indicators of the two generations of equipment is carried out.
  • China Rural Water and Hydropower. 2018, (12):  169-172. 
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    Abstract: In this paper, a method based on wavelet transform and SVD is proposed to extract vibration fault characteristics of hydropower units. The wavelet transform was used to transform the de-noised vibration signal of hydropower unit. The wavelet decomposition coefficients of each branch of the signal are obtained by the transformation. After single branch reconstructing the differences of the branch coefficients, the SVD input matrix is formed and the singular value is extracted to obtain the feature vector. Probabilistic neural networks are used to classify the extracted singular value features. The test results show that the method is simple and stable, with higher division and better recognition rate, which can provide an effective basis for the diagnosis of hydropower unit fault.
  • China Rural Water and Hydropower. 2018, (12):  173-177. 
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    In the process of transformation and optimization of the turbine governing system of Xiaolangdi Hydropower Station, there are some problems caused by compatibility between old and new equipments and design omission, such as matching after changing the type of on-off valve, misopening of proportional valve and decreasing the quality of regulation. After detailed analysis and research, the technical personnel adopted measures such as changing the connection mode of start-stop loop nodes, redundant configuration of proportional valve input signal and optimizing the regulation parameters in power regulation mode to solve the optimization one by one. The overall operation stability and safety of the optimized governing system have reached a higher level, and the defect rate of the equipment has been significantly reduced. After optimizing the load pilot curve and other measures, the dynamic and static regulation quality has been greatly improved, and the load overshoot ing has been significantly decreased.
  • China Rural Water and Hydropower. 2018, (12):  188-192. 
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    The software development and design is used to compute the dimensions of flowing passage of the bulb turbine, to achieve the features of generating drawings of the flowing section and sectional drawings of power house. A software applied to calculating the dimensions of bulb tubular turbine flowing passage has been designed, which can generate drawings of the flowing passage and sectional drawings of power house automatically. It was programmed separately in chapters dealing with the preliminary turbine selection and compute by the programming language of C# and .NET platform technology, which includes bulb ratio, the height of guide vane, the width of inlet tube, the distance of units, the throat diameter of runner chamber, the inlet diameter of draft tube, the length of draft tube and the angle of cone. It was used to compute the diameter of draft tube inlet by the linear fitting methods; It can be achieved the function of drawing and the export of CAD drawing by using GDI + drawing technology and AutoCAD secondary development. The software was verified to achieve the compute of dimensions of flowing passage of the bulb tubular precisely by an example, and it can generate complete CAD drawings of the flowing passage and sectional drawings of power house, and it is of a certain guiding significance for the design of the bulb turbine.