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Prediction of the Slope Solute Loss Based on BP Neural Network

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Computers, Materials & Continua 2021年第12期69卷 3871-3888页

作者： Xiaona Zhang Jie Feng Zhiguo Yu Zhen Hong Xinge Yun School of hydrology and water resources Nanjing University of Information Science&TechnologyNanjing210044China water resources Research Institute China Institute of Water Resources and Hydropower ResearchBeijing100044China Department of Geography and environmental Sustainability University of OklahomaNorman73071USA

The existence of soil macropores is a common *** to the existence of soil macropores,the amount of solute loss carried by water is deeply modified,which affects watershed hydrologic *** this study,a new improved BP(Back Propagation)neural network method,using Levenberg–Marquand training algorithm,was used to analyze the solute loss on slopes taking into account the soil *** rainfall intensity,duration,the slope,the characteristic scale of macropores and the adsorption coefficient of ions,are used as the variables of network input *** network middle layer is used as hidden layer,the number of hidden nodes is five,and a tangent transfer function is used as its neurons transfer *** cumulative solute loss on the slope is used as the variable of network output layer.A linear transfer function is used as its neurons transfer *** rainfall simulation experiments are conducted in indoor experimental tanks in order to verify this *** error analysis and the performance comparison between the proposed method and traditional gradient descent method are *** results show that the convergence rate and the prediction accuracy of the proposed method are obviously higher than that of traditional gradient descent *** addition,using the experimental data,the influence of soil macropores on slope solute loss has been further confirmed before the simulation.

关键词： Solute loss soil macropores improved BP neural network slope

Evaluation of Latest TMPA and CMORPH Precipitation Products with Independent Rain Gauge Observation Networks over High-latitude and Low-latitude Basins in China

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Chinese Geographical Science 2016年第4期26卷 439-455页

作者： JIANG Shanhu REN Liliang YONG Bin HONG Yang YANG Xiaoli YUAN Fei State Key Laboratory of hydrology-water resources and Hydraulic Engineering Hohai University School of Civil Engineering and environmental Sciences School of Meteorology University of Oklahoma

The Tropical Rainfall Measuring Mission （TRMM） Multi-satellite Precipitation Analysis （TMPA） and National Oceanic and Atmospheric Administration （NOAA） Climate Prediction Center （CPC） morphing technique （CMORPH） are two important multi-satellite precipitation products in TRMM-era and perform important functions in GPM-era. Both TMPA and CMORPH systems simultaneously upgraded their retrieval algorithms and released their latest version of precipitation data in 2013. In this study, the latest TMPA and CMORPH products （i.e., Version-7 real-time TMPA （T-rt） and gauge-adjusted TMPA （T-adj）, and Version- 1.0 real-time CMORPH （C-rt） and Version-l.0 gauge-adjusted CMORPH （C-adj）） are evaluated and intercompared by using independent rain gauge observations for a 12-year （2000--2011） period over two typical basins in China with different geographical and climate conditions. Results indicate that all TMPA and CMORPH products tend to overestimate precipitation for the high-latitude semiarid Laoha River Basin and underestimate it for the low-latitude humid Mishui Basin. Overall, the satellite precipitation products exhibit superior performance over Mishui Basin than that over Laoha River Basin. The C-adj presents the best performance over the high-latitude Laoha River Basin, whereas T-adj showed the best performance over the low-latitude Mishui Basin. The two gauge-adjusted products demonstrate potential in water resource management. However, the accuracy of two real-time satellite precipitation products demonstrates large variability in the two validation basins. The C-rt reaches a similar accuracy level with the gauge-adjusted satellite precipitation products in the high-latitude Laoha River Basin, and T-rt performs well in the low-latitude Mishui Basin. The study also reveals that all satellite precipitation products obviously overestimate light rain amounts and events over Laoha River Basin, whereas they underestimate the amount and events over Mishui Basin. The findings of

关键词： satellite precipitation Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) Cli-mate Prediction Center morphing technique (CMORPH) precision evaluation

Non-growing season soil CO_2 efflux and its changes in an alpine meadow ecosystem of the Qilian Mountains,Northwest China

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Journal of Arid Land 2013年第4期5卷 488-499页

作者： ZongQiang CHANG XiaoQing LIU Qi FENG ZongXi CHE HaiYang XI YongHong SU JianHua SI Alashan Desert Eco-hydrology Experimental Research Station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Gansu hydrology and water resources Engineering Center Academy of water Resource Conservation Forests in Qilian Mountains of Gansu Province

Most soil respiration measurements are conducted during the growing *** tundra and boreal forest ecosystems,cumulative,non-growing season soil CO2 fluxes are reported to be a significant component of these systems＇ annual carbon ***,little information exists on soil CO2 efflux during the non-growing season from alpine ***,comparing measurements of soil respiration taken annually versus during the growing season will improve the accuracy of estimating ecosystem carbon budgets,as well as predicting the response of soil CO2 efflux to climate *** this study,we measured soil CO2 efflux and its spatial and temporal changes for different altitudes during the non-growing season in an alpine meadow located in the Qilian Mountains,Northwest *** experiments on the soil CO2 efflux of alpine meadow from the Qilian Mountains were conducted along an elevation gradient from October 2010 to April *** measured the soil CO2 efflux,and analyzed the effects of soil water content and soil temperature on this *** results show that soil CO2 efflux gradually decreased along the elevation gradient during the non-growing *** daily variation of soil CO2 efflux appeared as a single-peak *** soil CO2 efflux was low at night,with the lowest value occurring between 02：00-06：***,values started to rise rapidly between 07：00-08：30,and then descend again between 16：00-18：*** peak soil CO2 efflux appeared from 11：00 to 16：*** soil CO2 efflux values gradually decreased from October to February of the next year and started to increase in ***-growing season Q10 （the multiplier to the respiration rate for a 10℃ increase in temperature） was increased with raising altitude and average Q10 of the Qilian Mountains was generally higher than the average growing season Q10 of the Heihe River ***,non-growing season soil CO2 efflux was relatively high in October and early spring and low in the *** soil CO2

关键词： non-growing season soil CO2 efflux spatial and temporal variation alpine meadow Q10 values Qilian Mountains

青藏高原东北部湖泊浮游植物对气候振荡的响应:来自1400年沉积物岩芯的证据

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Science Bulletin 2024年第9期69卷 1208-1211页

作者：张含笑郑佳楠王荣刘永高扬吴丰昌霍守亮 State Key Laboratory of environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China School of Geography and Ocean Science Nanjing UniversityNanjing 210023China State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China Key Laboratory of water and Sediment Science Ministry of EducationCollege of Environmental Science and EngineeringPeking UniversityBeijing 100871China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

The Tibetan Plateau, also known as the water Tower of Asia, is home to 1424 lakes with areas of greater than 1 km2, and supplies freshwater resources for more than 1.4 billion people [1,2]. In the context of recent global change, the warmer climate has caused prominent changes in the characteristics of the lake evolution on the Tibetan Plateau, such as changes in the hydrology.

关键词： Tibetan Plateau 青藏高原东北部

Prediction of Toxicity of Phenols and Anilines to Algae by Quantitative Structure-activity Relationship

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Biomedical and environmental Sciences 2008年第3期21卷 193-196页

作者： GUANG-HUA LU CHAO WANG XIAO-LING GUO State Key Laboratory for hydrology-water resources and Hydraulic Engineering College of Environmental Science and Engineering Hohai University Nanjing 210098 Jiangsu China

Objective To measure the toxicity of phenol, aniline, and their derivatives to algae and to assess, model, and predict the toxicity using quantitative structure-activity relationship （QSAR） method. Methods Oxygen production was used as the response endpoint for assessing the toxic effects of chemicals on algal photosynthesis. The energy of the lowest unoccupied molecular orbital （ELUMO） and the energy of the highest occupied molecular orbital （EHOMO） were obtained from the ChemOffice 2004 program using the quantum chemical method MOPAC, and the frontier orbital energy gap （△E） was obtained. Results The compounds exhibited a reasonably wide range of algal toxicity. The most toxic compound was α-naphthol, whereas the least toxic one was aniline. A two-descriptor model was derived from the algal toxicity and structural parameters： logl/EC50=0.2681ogKow-1.006△E＋11.769 （n=20, r^2=0.946）. This model was stable and satisfactory for predicting toxicity. Conclusion Phenol, aniline, and their derivatives are polar narcotics. Their toxicity is greater than estimated by hydrophobicity only, and addition of the frontier orbital energy gap AE can significantly improve the prediction of logKow-dependent models.

关键词： Toxicity QSARs Frontier orbital energy gap Prediction

An Improved Bald Eagle Search Algorithm with Cauchy Mutation and Adaptive Weight Factor for Engineering Optimization

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Computer Modeling in Engineering & Sciences 2023年第8期136卷 1603-1642页

作者： Wenchuan Wang Weican Tian Kwok-wing Chau Yiming Xue Lei Xu Hongfei Zang College of water resources Henan Key Laboratory of Water Resources Conservation and Intensive Utilization in the Yellow River BasinNorth China University of Water Resources and Electric PowerZhengzhou450046China Department of Civil and environmental Engineering The Hong Kong Polytechnic UniversityHong KongChina College of hydrology and water resources Hohai UniversityNanjing210024China

The Bald Eagle Search algorithm(BES)is an emerging meta-heuristic *** algorithm simulates the hunting behavior of eagles,and obtains an optimal solution through three stages,namely selection stage,search stage and swooping ***,BES tends to drop-in local optimization and the maximum value of search space needs to be *** fill this research gap,we propose an improved bald eagle algorithm(CABES)that integrates Cauchy mutation and adaptive optimization to improve the performance of BES from local ***,CABES introduces the Cauchy mutation strategy to adjust the step size of the selection stage,to select a better search ***,in the search stage,CABES updates the search position update formula by an adaptive weight factor to further promote the local optimization capability of *** verify the performance of CABES,the benchmark function of CEC2017 is used to simulate the *** findings of the tests are compared to those of the Particle Swarm Optimization algorithm(PSO),Whale Optimization Algorithm(WOA)and Archimedes Algorithm(AOA).The experimental results show that CABES can provide good exploration and development capabilities,and it has strong competitiveness in testing ***,CABES is applied to four constrained engineering problems and a groundwater engineeringmodel,which further verifies the effectiveness and efficiency of CABES in practical engineering problems.

关键词： Bald eagle search algorithm cauchymutation adaptive weight factor CEC2017 benchmark functions engineering optimization problems

A new assessment method for comprehensive impact of hydropower development on runoff and sediment changes

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Journal of Geographical Sciences 2012年第6期22卷 1034-1044页

作者：刘新有何大明 Asian International Rivers Center Yunnan University Yunnan Bureau of hydrology and water resources Management

The environmental impact assessment （EIA） of cascade dams building in international rivers has been widely discussed in China and ASEAN countries since the 1990s. In Southwest China, all the great mountainous rivers have been the major state base for large-scale hydropower development. Among these rivers, the environmental change and response of the watercourse under the cascade dams building in the upper Mekong （called Lancang River in China） has been the focus in recent 20 years. In this paper, the Lancang River, which has over 25 years of large-scale hydropower development, was chosen as a case study for establishing the affected evaluation indicators system and its regression model of runoff and sediment, determining the indicators weight by the hierarchy analysis method and factor analysis method, and setting up the quantitative evaluation models of indicators affected level based on the ＂marginal efficiency＂ principle. Using these methods and model established, the influence degree of runoff and sediment in the Lancang River from 1986 to 2007 were assessed. The major results are：（1） the impact of sediment transport change by the cascade development is much higher than that of the runoff change; （2） the years＇ number with different impact levels respectively are 72.7% as the ＂smallest＂ level, 18.2% as ＂smaller＂, and 9.1% as ＂general＂; （3） the change process of runoff and sediment shows a ＂U-shaped＂ pattern, which indicates the balance of sediment change because of the interaction of sediment reduction by Manwan reservoir storage and the increase by the Dachaoshan dam construction.

关键词： assessment method runoff and sediment features hydropower development Lancang River

Evaluation and Hydrological Application of CMADS Reanalysis Precipitation Data against Four Satellite Precipitation Products in the Upper Huaihe River Basin, China

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Journal of Meteorological Research 2020年第5期34卷 1096-1113页

作者： Shanhu JIANG Ruolan LIU Liliang REN Menghao WANG Junchao SHI Feng ZHONG Zheng DUAN State Key Laboratory of hydrology-water resources and Hydraulic Engineering Hohai UniversityNanjing 210098China hydrology and water resources Monitoring and Forecasting Center Ministry of Water ResourcesBeijing 100053China Department of Physical Geography and Ecosystem Science L und UniversityLund S-22362Sweden

Satellite-and reanalysis-based precipitation products are important data source for precipitation, particularly in areas with a sparse gauge network. Here, five open-access precipitation products, including the newly released China Meteorological Assimilation Driving Datasets for the Soil and water Assessment Tool(SWAT) model(CMADS)reanalysis dataset and four widely used bias-adjusted satellite precipitation products [SPPs;i.e., Tropical Rainfall Measuring Mission(TRMM) Multisatellite Precipitation Analysis 3B42 Version 7(TMPA 3B42V7), Climate Prediction Center(CPC) morphing technique satellite–gauge blended product(CMORPH-BLD), Climate Hazards group Infrared Precipitation with Station Data(CHIRPS), and Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks–Climate Data Record(PERSIANN-CDR)], were assessed. These products were first compared with the gauge observed data collected for the upper Huaihe River basin, and then were used as forcing data for streamflow simulation by the Xin’anjiang(XAJ) hydrological model under two scenarios with different calibration procedures. The performance of CMADS precipitation product for the Chinese mainland was also assessed. The results show that:(1) for the statistical assessment, CMADS and CMORPH-BLD perform the best, followed by TMPA 3B42V7, CHIRPS, and PERSIANN-CDR, among which the correlation coefficient(CC) and rootmean-square error(RMSE) values of CMADS are optimal, although it exhibits certain significant negative relative bias(BIAS;-22.72%);(2) CMORPH-BLD performs the best in capturing and detecting rainfall events, while CMADS tends to underestimate heavy and torrential precipitation;(3) for streamflow simulation, the performance of using CMADS as input is very good, with the highest Nash–Sutcliffe efficiency(NSE) values(0.85 and 0.75 for calibration period and validation period, respectively);and(4) CMADS exhibits high accuracy in eastern China while with significant negative BIAS,

关键词： reanalysis precipitation data China Meteorological Assimilation Driving Datasets for the Soil and water Assessment Tool(SWAT)model(CMADS) satellite precipitation hydrological evaluation Xin’anjiang(XAJ)hydrological model

Observed displacement data-based identification method of deformation time-varying effect of high concrete dams

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Science China(Technological Sciences) 2018年第6期61卷 906-915页

作者： WANG ShaoWei GU ChongShi BAO TengFei l School of environmental and Safety Engineering Changzhou University Changzhou 213164 China State Key Laboratory of hydrology-water resources andHydraulic Engineering Hohai University Nanjing 210098 China

The long-term safety of high concrete dams has become the focus and central issues of public attention. Deformation is an actual comprehensive reflection of concrete dams. Especially the deformation time-varying effect, is a key index for evaluating the structural behavior, health status, and their evolution of a concrete dam in long-term service. In this paper, causing factors of the deformation time-varying effect of concrete dams were analyzed, and the time-varying effect was divided into two parts, which are the inherent time-varying effect and the time-varying effect caused by the change of dam structural performance. Then, based on the observed dam displacement and the wavelet multi-resolution analysis, causal models for identifying the later deformation time-varying effect and the identification process were proposed. Finally, the efficiency and rationality of the proposed method were verified by two actual concrete dams with runoff reservoir and regulatory reservoir.

关键词： high concrete dam deformation time-varying effect causing analysis identification method