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    15 May 2016, Issue 5
      
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  • China Rural Water and Hydropower. 2016, (5):  23-26. 
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    For the health of the river in Jiangsu Province, this paper proposes a new system of river health assessment method, This model consists of three prediction methods and three comprehensive index methods. Firstly, exploratory evaluating sixteen backbone rivers in Jiangsu Province, Filtering method of screening model system to assessment river health in Jiangsu Province, After the model is streamlined and then applying it to evaluate river health of the overall Jiangsu Province. The results show that overall rivers in Jiangsu Province are in the "sub-healthy" (Class II, etc.) level. So it is necessary to pay attention to river and lake health management, and maintaining healthy life of rivers.
  • China Rural Water and Hydropower. 2016, (5):  33-36. 
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    Land-use change and its response analysis has important practical significance to the sustainable development of the region. Based on the data of land use in 2005 and 2012 ,by constructing the Markov model and ecosystem service value table , its combined with the related general land use planning, and carries out dynamic simulation and prediction on the landscape pattern of Zhangjiagang and its ecosystem service value from 2019-2026. The results showed that between 2005-2012, changes in land use types plaque area of 9996.12hm2, arable land and waters appear relatively substantially reduced, main transfer for towns and construction land and garden plot; According to the current Temporal and Spatial Trends, 2019-2026, the construction area will continue to increase, water and arable land continues to decline. Leading to its ecological response is negative, and ecosystem service value reduced year by year, the rate is 11.5557 million yuan / a, including food production, gas regulation, climate regulation, hydrology regulation, maintain biodiversity and waste treatment significantly reduce, it may lead to the problem such as environmental deterioration, biodiversity loss in the study area. The government should take timely measures to strengthen the protection of arable land and water area, reduce the construction land expansion rate, change the present trend of land use change, keep the ecosystem health.
  • China Rural Water and Hydropower. 2016, (5):  37-40. 
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    In order to alleviate water crisis and the contradiction between supply and demand of water resources, water transfer project is one of the indispensable and effective measures. In the process of application and management, however, the project changes the water regime. The original ecological balance will be broken and the project also has negative effects on the society, ecology and economy. Therefore, it is necessary for us to analysis and assess the sustainability of the water supply areas. This article combines the emergy theory with the traditional method of ecological footprint, to construct emergy-ecological footprint analysis model. By calculating the per capita emerge ecological carrying capacity, per capita emerge ecological footprint and sustainability index, it measures the environmental sustainable development status of water supply areas of one water diversion project in northwest China, to provide references for the rational allocation of water resources, with the goal of sustainable development.
  • China Rural Water and Hydropower. 2016, (5):  55-57. 
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    Rain-water storage and controllable irrigation is an effective way to reduce the pollutant load of nitrogen and phosphorus in rice field. This paper analyzed the difference of concentration and load of nitrogen and phosphorus on the scale of farmland and farm ditch between the modes of light drought- low storage(T1) and light drought- hight storage(T2) throught plot experiment. The results showed that load of TP and TN in treatment T2 were absolutely lower than in treatment T1 on the scale of farmland, and the decreasing range was respectively 58.6% and 58.5%, and was respectively decreased 59.7% and 64.8% on the scale of farm ditch. The rainfall should be drained off as few as possible in the first 8 to14 hours, in order to let it stay in the chequered field for more than 14 hours.
  • China Rural Water and Hydropower. 2016, (5):  72-76. 
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    This paper taking Caitang-a medium reservoir irrigation district in the Nanfeihe canal as an example, constructing a comprehensive simulation model to calculate the water quantity balance in crop feilds, pools and reservoirs. Established in paddy field, dam, reservoir simulation model for water resources system using software Vensim .The results shows that the proposed model meets the demands of simulation on reservoir-pool water resources system in irrigation district, and provides the basic support for semi-distributed simulation of water resources system in large-scaled irrigation district.
  • China Rural Water and Hydropower. 2016, (5):  77-80. 
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    In this study, soil water infiltration pathway was studied by using single ring infiltration permeameter and dye tracer experiment. The experiment was implemented at an experimental station, viz., the Hemuqiao station located in the Jangwan catchment in Taihu basin. Research results show that preferential flow caused by the roots, wormholes and gravel channels widely exist in the soil at the humid hilly area of Hemuqiao station. Soil permeability is good and infiltration rate is greater than the regular rainfall intensity. That is to say, runoff will not occur until soil is saturated, i.e., saturated infiltration will prevail during the whole processes of runoff generation. In addition, the results of the dye tracer experiments also show that most of the soil water is vertical movement in the surface area of the hillside (<70cm, less than the depth of the impervious layer) and a small amount of lateral flow is mainly caused by soil macropores.
  • China Rural Water and Hydropower. 2016, (5):  81-87. 
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    Global climate change has become an unchangeable fact, it directly affects the land evapotranspiration and water balance. Located in the northwest inland areas of China, Heihe River Basin is lack of water resources and the ecological environment in this area is fragile. Based on the Gis technology, Mann-kendall nonparametric test and Pettitt change-point analysis, the temporal-spatial characteristics of wind speed, temperature, humidity, net radition and reference evapotranspiration were investigated for 16 meteorological stations including nine stations in Heihe River Basin and six stations near the basin during 1960-2012. Then, for the nine stations in the Heihe River Basin, by regression analysis, the influence of climate variables change on ET0 was also assessed quantitatively. The results showed that in the past 53 years annual wind speed, humidity and net radition had decreasing trends with time, while temperature had a significant increasing trend.Under the background of climate change, the changes of ET0 in Ejinaqi and Gaotai played a decisive role in the basin change,and ET0 in the river basin had a decreasing trend with an average value of 0.37 mm per year, Annual ET0 in every station was related positively to temperature,wind speed and net radition, but related negatively to humidity; Temperature and wind speed were the main factors influencing ET0. Both in climate variables and ET0, there were clear change-points and spatial-temporal differences, which were closely related to the complicated relation between ET0 and climate variables.
  • China Rural Water and Hydropower. 2016, (5):  97-100. 
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    The selection of typical hydrologic year is an important element in the research of water resource dispatch, which also plays a key role in hydrological characteristics analysis. In view of the defect of human subjectivity in conventional frequency method, a novel method that based on cloud model is proposed. In this method, the cloud transformation is first used to extract the conceptual models of runoff time series. Then, the historical data are elastically classified to new concepts by using a new conception zooming method, which takes the influence of the magnitude coefficient into consideration. Simulation experiment results show that the concept center extracted by the proposed method is in close to that obtained by conventional method. Besides, the results are different in that the proposed method can also describe the concepts with uncertainty, which makes it more accurate for the analysis of hydrological characteristics.
  • China Rural Water and Hydropower. 2016, (5):  109-112. 
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    With the development of society and economy, water intake project is becoming more and more important. There are more and more water source project with high amplitude water level. In order to reduce investment outlay and improve the working conditions, mobile water pump station is adopted. The design proposal of water intake project for Dakou waterworks in Wanshi Town Songzi City Hubei Province is given. The considerations, condition of compatibility and design of water intake are all addressed to fit for different kind of water intake structures in the proposal. Small mobile water pump station is worthy of promotion and application in all kinds of water intake projects.
  • China Rural Water and Hydropower. 2016, (5):  113-116. 
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    Aiming at the Kamalapur rainwater pumping station, his forebay is very complex turbulent flow. Using the standard k-ε double equation and Reynolds average Navier Stokes (N-S) equations, Turbulent flow model is established to apply in the forebay. The given boundary conditions, through the Fluent, the hydraulic characteristics of the forebay are studied by numerical simulation. The simulation results agree well with the hydraulic model test, the forebay operation flow conditions meet the requirements, no harmful vortex exists, These provide the basis for the safe operation of pumping stations, and also provide a reference for the similar rainwater pumping station design and operation.
  • China Rural Water and Hydropower. 2016, (5):  121-125. 
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    Abstract: Complex geological conditions is disadvantage to the stability against sliding of dam. Especially when there are many structural planes cut into rock each other,the rock mass integrity is crippled. It make a larger effect on abutment stability against sliding. A RCC high arch dam’maximum dam height is 132m,the geological conditions of dam site area is complicated, fault and fracture with dense are crisscrossed,interlayer shear zone across the valley, the stability of dam abutment is very serious. In order to explore the impacts of structural planes on dam abutment stability and deformation under complex geological conditions, the method of 3D geomechanical overload damage experiment and finite element calculation was used to analysis of structural plane displacement. It reveals that structural planes which influence the stability of the left abutment are f5、f4、Lp285、L2、fj2、fj3、fj4, structural planes which influence the stability of the right abutment are f4、Lp4-x、fj3、fj4. The test for overall stability of nonlinear deformation overload safety coefficient t is K2=3.4 ~ 4.3, finite element calculation conclusion that K2= 3.0 ~ 4.0, the overall stability of dam abutment meet the requirements. On this basis, according to the abutment structural plane occurrence and combination , using the block theory to study on the instability of the typical slide block, summarizes the critical slip surface instability of determining interval. The results show that, the "key block" of three typical blocks in dam abutment on both sides is located in the left bank. Its safety factor is 2.4~3.0. It indicates that complex structure plane will have weaken the stability of dam abutment which need to be further processed to improve the abutment stability against sliding.
  • China Rural Water and Hydropower. 2016, (5):  126-128. 
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    The activity of limestone powder, as well the effects of limestone powder on the properties of concrete were studied in this paper. The results show that the activity of limestone powder was weaker than the class I fly ash,the strengths of mortars and concretes added with 30% limestone powder were weaker compared with the plain concrete and fly ash concrete. The cooperation of limestone powder and fly ash together can improve the particle size distribution of the cementitious systems, thereby enhancing the early concrete strength slightly. The impermeability, frost resistance of concrete was not clearly weakened when less than 10% of powder was used.
  • China Rural Water and Hydropower. 2016, (5):  133-135. 
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    Little information could be found about formulas and coefficients for calculating the head loss of tube settler, which makes it difficult for the designers to get the values. Herein, using computational fluid dynamics software FLUENT as the platform, the hydraulic characteristics involving in water flow regime, velocity distribution and pressure distribution of flow were studied via the standard k-? turbulence model with the SIMPLEC algorithm and numerical simulation on the flow in tube settler based on the assumptions that the free water surface remains flat as a stress-free plane of symmetry and the velocity distribution and free outflow are prescribed on inlet and outlet boundaries respectively. The head loss of the tube settler was obtained from the numerical simulation, which was in good agreement with the measurement for actual engineering.
  • China Rural Water and Hydropower. 2016, (5):  141-144. 
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    In view of the characteristic that index concept randomness and fuzziness coexist in the process of reservoir slope stability evaluation, a new stability evaluation model was proposed to the evaluation of slope stability based on improved analytic hierarchy process and cloud model theory. On this basis , using the slope stability evaluation standard and the theory of cloud model to distinguish the certainty grade of evaluation index sample, and then determine it’s level. By this, a reservoir slope stability evaluation model was found which coupling improved analytic hierarchy process and cloud method ,then put forward the concrete implementation process. Finally, the model was applied to the slope stability analysis of the left bank hydropower station of Jin ping-I Hydropower Station, compared the evaluation results with other evaluation methods, the results show that the slope stability analysis model is effective and feasible, this model not only improves the analysis efficiency, but also consider the stability level of fuzziness and the randomness of the measured values.
  • China Rural Water and Hydropower. 2016, (5):  145-149. 
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    Abstract: In view of the serious situation that the concrete lining canals have been damaging by the frost heaving in the irrigation area of Ningxia, the mechanical model of frost heaving damage to the composite lining canal with splicing double arc-plates has been established. The internal force distribution and the anti-frost heaving effect of concrete lining have been investigated under considering the friction between the geomembrane and channel soil. And the analysis procedure was explained by using an example. Compared with the rigid concrete lining canal, the tangential force of constraint of the lining canal is reduced by adding the compound geomembrane, the stress condition of the lining structure is also improved because of a number of allowable displacements of frost heave, the distribution of the frost-heave capacity is more balanced, frost heaving force and frozen force is decreased while tensile strength is increased. So the anti-freeze bilge ability of concrete lining canal is enhanced.
  • China Rural Water and Hydropower. 2016, (5):  153-156. 
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    In order to study the stability of the spillway chute slabs, the characteristics of uplift force acted on the spillway chute slabs are investigated by performing model tests. Based on the model test results, Uplift force in unit area acted on the spillway chute slabs was increased as the flow-energy ratio (R) elevated;The irregularity had significant effect on uplift force acted on the spillway chute slabs. The standard deviation and maximum of uplift force was increased as the irregularity height elevated,at the same time, the standard deviation and maximum of uplift force was decreased as the relative irregularity height was increased. Probability density of uplift force was in accordance with normal distribution. The dominant frequency of uplift force distributed in low frequency. The smaller was the maximum of uplift force,the bigger was the area of chute slabs .
  • China Rural Water and Hydropower. 2016, (5):  157-159. 
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    Plate flat bit cutting groove method is based on shock into slot method, impact on cross drill bit (or circle) are replaced with plate sector bit to improve, to the construction of diaphragm wall strata cutting groove, to adopt positive and reverse circulation at the same time with the same slot method instead of the traditional sand suction tube is improved by the techniques such as slag forming a cut-off slot construction method. This method successfully solved the sandy pebble, boulder, boulders foundation and strong weathering difficulty in construction of diaphragm wall slot the batholith.
  • China Rural Water and Hydropower. 2016, (5):  160-162. 
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    Studies on concrete subjected to triaxial compressive properties of static and dynamic by using static and dynamic triaxial apparatus are carried out, analyzed the mechanical and deformation characteristics of concrete at different hydraulic(0MPa、2MPa、5MPa、10MPa、) and loading rate(10-5/s、10-4/s、10-3/s、10-2/s). Test results show that the compressive strength with strain rate increases, increases with confining pressure; peak strain with strain rate increases overall, with increasing confining pressure did not change significantly; elasticity modulus decreases with increasing loading rate showed an increasing trend, less loaded with relevance to the environment. The failure pattern of concrete with strain rate and loading conditions is considered less relevant
  • China Rural Water and Hydropower. 2016, (5):  163-170. 
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    Multiwavelets have such features as short support, orthogonality, symmetry and vanishing moments. Therefore, multiwavelets offer the possibility of superior performance for signal de-noising, compared with wavelets. After multiwavelets decomposition, if the current coefficient contains certain components of the signal, its neighboring coefficients may also contain these ingredients. Based on this, we put forward the multiwavelets neighboring coefficients de-noising method. We apply this method to hydropower unit vibration signal de-noising, settling down the contradiction between restraining noisy pollution and reserving signal details by the traditional wavelets threshold de-noising. After de-noising the simulation signal, we find that multiwavelets neighboring coefficients de-noising method gives better performance both at SNR and RMSE than wavelets threshold de-noising method. For the factual hydropower unit vibration signal, according to the integrity degree of vibration characteristic components, we discover that multiwavelets neighboring coefficients de-noising method can filter the noise more thoroughly and retain the characteristic ingredients more completely, showing a better performance.
  • China Rural Water and Hydropower. 2016, (5):  171-173. 
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    Hydropower station tailrace riverbed always become a narrow flow cross-section beam due to flood scouring and river dredging does not meet the design requirements,Then the rised tail water has great influence on the power generation efficiency. In this paper,We use catia to establish the numerical model,and use fluent to simulate the water surface profile and Flow Field . the Numerical simulation results have a good agreement with the experimental data which show that the computation method are very effective. Four dredging program numerical results indicate that Reasonable and effective dredging scheme can greatly reduce the power station tailrace and increase power generation efficiency.
  • China Rural Water and Hydropower. 2016, (5):  183-188. 
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    The AFSA, applied in reservoir generation optimal dispatching, is weak in searching capacity at the later searching stages. It is easy to fall into the difficulty of getting partial solving, and it runs a relatively long time. The precision of optimal solution can be improved by increasing the chaotic optimal searching function of one single fish, but the problem of computing time increased is produced. Based on multi-core computers interconnected, a double-layer parallel computing architecture is designed for CAFSA in reservoir generation optimal dispatching. The computing results of reservoir instance simulation show that the parallel strategy can effectively maintain the high quality of CAFSA. It can greatly reduce the computing time and provide a certain direction for improving the solving efficiency of the scheduling model.
  • China Rural Water and Hydropower. 2016, (5):  196-200. 
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    Comprehensive construction project for Smart grid is constituted by the distributed energy system, intelligent substation system, intelligent communication platform and other subprojects. Due to differences in technical characteristics and function orientation, These sub-projects are largely very in the benefits,thus make different contributions to the goal of the whole comprehensive construction project. By analyzing the contribution of each sub-project for integrated projects, not only can we scientifically evaluate the importance of each project to the total project, but also provide reference for comprehensive engineering development direction. In this paper, the general benefit evaluation index system of the smart grid comprehensive construction project is established, the direct contribution value of each subproject, the definition and calculation method of contribution matrix are proposed, Then the contribution analysis model of subproject to the whole construction project is put forward. Based on the smart grid integrated construction project in Zhengzhou high-tech development zone, the model results show that the sub-projects related to smart meters, monitoring equipment, and intelligent power transmission and distribution contribute more to the smart grid integrated construction project; the electric car related subprojects however contribute less. Therefore, The research and development, capital investment and construction quality of intelligent monitoring and power transmission systems must be attached great importance, the development of electric vehicles should be paid close attention, and the investment in electric car project need to be timely increased.