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Effects of Rainfall and Underlying Surface on Flood Recession——The Upper Huaihe River Basin Case

International Journal of Disaster Risk Science 2021年第1期12卷 111-120页

作者： Yashan Cheng Yanfang Sang zhonggen wang Yuhan Guo Yin Tang Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

The effects of rainfall and underlying surface conditions on flood recession processes are a critical issue for flood risk reduction and water use in a region.In this article,we examined and clarified the issue in the upper Huaihe River Basin where flood disasters frequently occur.Data on 58 rainstorms and flooding events at eight watersheds during 2006–2015 were collected.An exponential equation(with a key flood recession coefficient)was used to fit the flood recession processes,and their correlations with six potential causal factors—decrease rate of rainfall intensity,distance from the storm center to the outlet of the basin,basin area,basin shape coefficient,basin average slope,and basin relief amplitude—were analyzed by the Spearman correlation test and the Kendall tau test.Our results show that 95%of the total flood recession events could be well fitted with the coefficient of determination(R2)values higher than 0.75.When the decrease rate of rainfall intensity(Vi)is smaller than 0.2 mm/h2,rainfall conditions more significantly control the flood recession process;when Vi is greater than 0.2 mm/h2,underlying surface conditions dominate.The result of backward elimination shows that when Vi takes the values of0.2–0.5 mm/h2 and is greater than 0.5 mm/h2,the flood recession process is primarily influenced by the basin’s average slope and basin area,respectively.The other three factors,however,indicate weak effects in the study area.

关键词： Backward elimination China Correlation test Flood recession Huaihe River Basin Rainfall intensity

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基于变速趋近律的PMSM复合速度控制

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制造技术与机床 2024年第6期 95-101页

作者：朱小兵王仲根高晓嵩安徽理工大学电气与信息工程学院安徽淮南232001

为了提高永磁同步电机速度控制器的性能,文章提出一种新型变速趋近律滑模控制策略。变速趋近律在传统指数趋近律的基础上引入关于系统状态的幂次项和关于滑模函数的变速项,并采用双曲正切函数来减小高频切换项的影响。该控制策略有利于... 详细信息

为了提高永磁同步电机速度控制器的性能,文章提出一种新型变速趋近律滑模控制策略。变速趋近律在传统指数趋近律的基础上引入关于系统状态的幂次项和关于滑模函数的变速项,并采用双曲正切函数来减小高频切换项的影响。该控制策略有利于减小电流和转矩脉动,提高了系统运行的稳定性和响应速度。另外,针对系统受未知干扰影响的问题,设计了一种滑模扰动观测器来估计系统的总扰动,并将估计的扰动补偿到复合速度控制器中。最后,利用Matlab/Simulation仿真和电机实验平台对所提出的控制策略进行验证。仿真和实验结果表明,复合速度控制器与扰动观测器相结合的控制策略具有更快的收敛速度、更小的抖振和更好的抗扰性能。

关键词：永磁同步电机滑模控制变速趋近律扰动观测器

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Multilevel Characteristic Basis Function Method with ACA for Accelerated Solution of Electrically Large Scattering Problems

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第3期35卷 449-454页

作者： Li Chenlu Sun Yufa wang zhonggen wang Guohua Key Laboratory of Intelligent Computing & Signal Processing Ministry of EducationAnhui University College of Electrical and Information Engineering Anhui University of Science and Technology

The multilevel characteristic basis function method(MLCBFM)with the adaptive cross approximation(ACA)algorithm for accelerated solution of electrically large scattering problems is studied in this paper.In the conventional MLCBFM based on Foldy-Lax multiple scattering equations,the improvement is only made in the generation of characteristic basis functions(CBFs).However,it does not provide a change in impedance matrix filling and reducing matrix calculation procedure,which is time-consuming.In reality,all the impedance and reduced matrix of each level of the MLCBFM have low-rank property and can be calculated efficiently.Therefore,ACA is used for the efficient generation of two-level CBFs and the fast calculation of reduced matrix in this study.Numerical results are given to demonstrate the accuracy and efficiency of the method.

关键词： multilevel characteristic basis function method(MLCBFM) adaptive cross approximation(ACA) characteristic basis functions(CBFs) electromagnetic scattering

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Two universal runoff yield models： SCS vs. LCM

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Journal of Geographical Sciences 2015年第3期25卷 311-318页

作者： LI Jun LIU Changming wang zhonggen LIANG Kang Key Laboratory of Water Cycle & Related Land Surface Processes Institute of Geographic Sciences andNatural Resources Research CAS Beijing 100101 China

Runoff calculation is one of the key components in the hydrological modeling. For a certain spatial scale, runoff is a very complex nonlinear process. Currently, the runoff yield model in different hydrological models is not unique. The Chinese LCM model and the American SCS model describe runoff at the macroscopic scale, taking into account the rela- tionship between total actual retention and total rainfall and having a certain similarity. In this study, by comparing the two runoff yield models using theoretical analyses and numerical simulations, we have found that：（1） the SCS model is a simple linear representation of the LCM model, and the LCM model reflects more significantly the nonlinearity of catchment runoff. （2） There are strict mathematical relationships between parameters （R, r） of the LCM model and between parameters （S） of the SCS model, respectively. Parameters （R, r） of the LCM can be determined using the research results of the SCS model parameters. （3） LCM model parameters （R, r） can be easily obtained by field experiments, while SCS parameters （S） are difficult to measure. Therefore, parameters （R, r） of the LCM model also can provide the foundation for the SCS model. （4） The SCS model has a linear relationship between the reciprocal of total actual retention and the reciprocal of total rainfall during runoff period. The one-order terms of a Taylor series expansion of the LCM model describe the same relation- ship, which is worth further study.

关键词： rainfall infiltration runoff calculation nonlinearity the SCS model the LCM model

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Assessing the impacts of climate variability and human activities on streamflow in the water＇ source area of Baiyangdian Lake

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Journal of Geographical Sciences 2012年第5期22卷 895-905页

作者： HU Shanshan LIU Changming ZHENG Hongxing wang zhonggen YU Jingjie Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100049 China College of Water Sciences Beijing Normal University Beijing 100875 China

As the largest wetland in the North China Plain （NCP）, the Baiyangdian Lake plays an important role in maintaining water balance and ecological health of NCP. Ir the past few decades, the decreasing streamflow in the Baiyangdian Basin associated with climate vari- ability and human activities has caused a series of water and eco-environmer,tal issues. In this study, we quantified the impacts of climate variability and human activities on streamflow in the water source area of the Baiyangdian Lake, based on analyses of hydrologic changes of the upper Tanghe river catchment （a sub-basin of the Baiyangdian Basin） from 1960 to 2008. Climate elasticity method and hydrological modeling method were used to distinguish the effects of climate variability and human activities. The results showed that the annual streamflow decreased significantly （P〉0.05） by 1.7 mm/a and an abrupt change was identi- fied around the year 1980. The quantification results indicated that climate variations ac- counted for 38%-40% of decreased streamflow, while human activities accounted for 60%--62%. Therefore, the effect of human activities played a dominant role on the decline of the streamflow in the water source area of the Baiyangdian Lake. To keep the ecosystem health of the Baiyangdian Lake, we suggest that minimum ecological water demand and in- tegrated watershed management should be guaranteed in the future.

关键词： climate variability human activities climate elasticity hydrological model Baiyangdian Lake Tanghe River

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Spatial and temporal variability of daily precipitation in Haihe River basin, 1958-2007

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Journal of Geographical Sciences 2010年第2期20卷 248-260页

作者： CHU Jianting XIA Jun XU Chongyu LI Lu wang zhonggen Key Laboratory of Water Cycle ＆ Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100039 China Institute of Physics ＆ Meteorology University of Hohenheim Garbenstr. 30 D-70955 Stuttgart Germany Department of Geosciences University of Oslo P O BOX 1047 Blindern N-0316 Oslo Norway

The seasonal variability and spatial distribution of precipitation are the main cause of flood and drought events. The study of spatial distribution and temporal trend of precipitation in river basins has been paid more and more attention. However, in China, the precipitation data are measured by weather stations （WS） of China Meteorological Administration and hydrological rain gauges （RG） of national and local hydrology bureau. The WS data usually have long record with fewer stations, while the RG data usually have short record with more stations. The consistency and correlation of these two data sets have not been well understood. In this paper, the precipitation data from 30 weather stations for 1958-2007 and 248 rain gauges for 1995-2004 in the Haihe River basin are examined and compared using linear regression, 5-year moving average, Mann-Kendall trend analysis, Kolmogorov-Smirnov test, Z test and F test methods. The results show that the annual precipitation from both WS and RG records are normally distributed with minor difference in the mean value and variance. It is statistically feasible to extend the precipitation of RG by WS data sets. Using the extended precipitation data, the detailed spatial distribution of the annual and seasonal precipitation amounts as well as their temporal trends are calculated and mapped. The various distribution maps produced in the study show that for the whole basin the precipitation of 1958-2007 has been decreasing except for spring season. The decline trend is significant in summer, and this trend is stronger after the 1980s. The annual and seasonal precipitation amounts and changing trends are different in different regions and seasons. The precipitation is decreasing from south to north, from coastal zone to inland area.

关键词： climate change spatial and temporal variability of precipitation Mann-Kendall method Kolmogorov-Smirnov test Z test F test Haihe River basin

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Development of Hydro-Informatic Modelling System and its application

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Science China(Technological Sciences) 2008年第4期51卷 456-466页

作者： LIU ChangMing wang zhonggen ZHENG HongXing ZHANG Lu WU XianFeng Key Laboratory of Water Resources and Related Land Surface Processes Institute of Geographical Sciences and Natural ResourcesChinese Academy of SciencesBeijing 100101China College of Water Sciences Beijing Normal UniversityBeijing 100875China CSIRO Land and Water Christian LaboratoryGPO Box 1666CanberraA.C.T.2601Australia Environmental Protection Administration Beijing 100101China

The understanding of hydrological cycle is the core of hydrology and the scientific base of water resources management. Meanwhile, simulation of hydrological cycle has long been regarded as an important tool for the assessment, utilization and protection of water resources. In this paper, a new tool named Hydro-Informatic Modelling System (HIMS) has been developed and introduced with case studies in the Yellow River Basin in China and 331 catchments in Australia. The case studies showed that HIMS can be employed as an integrated platform for hydrological simulation in different regions. HIMS is a modular based framework of hydrological model designed for different utilization such as flood forecasting, water resources planning and evaluating hydrological impacts of climate change and human activities. The unique of HIMS is its flexibility in providing alternative modules in the simulation of hydrological cycle, which successfully overcome the difficulties in the availability of input data, the uncertainty of parameters, and the difference of rainfall-runoff processes. The modular based structure of HIMS makes it possible for developing new hydrological models by the users.

关键词： HIMS model customization hydrological cycle water resources

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Evapotranspiration estimation methods in hydrological models

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Journal of Geographical Sciences 2013年第2期23卷 359-369页

作者： ZHAO Lingling XIA Jun XU Chong-yu wang zhonggen SOBKOWIAKLeszek LONG Cangrui KeyLaboratoryofWaterCycle&RelatedLandSurfaceProcesses.InstituteofGeographicSciencesandNaturalResourcesReseamh GASBeijing100101China GraduateUniversityofChineseAcademyofSciences Beijing100049China StateKeyLab.ofWaterResources&HydropowerEngineeringScience WuhanUniversityWuhan430072China DepartmentofGeosciences UniversityofOsloOsloNorway DepartmentofHydrologyandWaterManagement InstituteofPhysicalGeogmphyandEnvironmentalPlanningAdamMickiewiczUniversityPoznanPoland PuyangWaterConservancyBureau Puyang457000HenanChina

Actual evapotranspiration is a key process of hydrological cycle and a sole term that links land surface water balance and land surface energy balance. Evapotranspiration plays a key role in simulating hydrological effect of climate change, and a review of evapotranspiration estimation methods in hydrological models is of vital importance. This paper firstly summarizes the evapotranspiration estimation methods applied in hydrological models and then classifies them into the integrated converting methods and the classification gathering methods by their mechanism. Integrated converting methods are usually used in hydrological models and two differences exist among them： one is in the potential evaporation estimation methods, while the other in the function for defining relationship between potential evapora tion and actual evapotranspiration. Due to the higher information requirements of the Pen- man-Monteith method and the existing data uncertainty, simplified empirical methods for calculating potential and actual evapotranspiration are widely used in hydrological models. Different evapotranspiration calculation methods are used depending on the complexity of the hydrological model, and importance and difficulty in the selection of the most suitable evapotranspiration methods is discussed. Finally, this paper points out the prospective de velopment trends of the evapotranspiration estimating methods in hydrological modeling.

关键词： hydrological model actual evaporation potential evaporation function of soil moisture

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Bayesian-combined wavelet regressive modeling for hydrologic time series forecasting

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Chinese Science Bulletin 2013年第27期58卷 3796-3805页

作者： SANG YanFang SHANG LunYu wang zhonggen LIU ChangMing YANG ManGen Key Laboratory of Water Cycle & Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions Chinese Academy of Sciences School of Geographical Sciences Fujian Normal University

Wavelet regression(WR)models are used commonly for hydrologic time series forecasting,but they could not consider uncertainty evaluation.In this paper the AM-MCMC(adaptive Metropolis-Markov chain Monte Carlo)algorithm was employed to wavelet regressive modeling processes,and a model called AM-MCMC-WR was proposed for hydrologic time series forecasting.The AM-MCMC algorithm is used to estimate parameters’uncertainty in WR model,based on which probabilistic forecasting of hydrologic time series can be done.Results of two runoff data at the Huaihe River watershed indicate the identical performances of AM-MCMC-WR and WR models in gaining optimal forecasting result,but they perform better than linear regression models.Differing from the WR model,probabilistic forecasting results can be gained by the proposed model,and uncertainty can be described using proper credible interval.In summary,parameters in WR models generally follow normal probability distribution;series’correlation characters determine the optimal parameters values,and further determine the uncertain degrees and sensitivities of parameters;more uncertain parameters would lead to more uncertain forecasting results and hard predictability of hydrologic time series.

关键词：时间序列预测水文时间序列回归建模小波线性回归模型贝叶斯 MCMC算法合并

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应用改进的主要特征基函数快速计算目标宽角度RCS

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电子与信息学报 2018年第3期40卷 573-578页

作者：王仲根唐晓菀汪强安徽理工大学电气与信息工程学院淮南232001

特征基函数法是分析目标宽角度电磁散射特性的有效方法之一,但在构造特征基函数时,设置的入射波激励包含大量的冗余信息,大大降低了特征基函数的构造效率;另外在分析复杂目标时,在增加激励数目的情况下,仅应用主要特征基函数并不能显著... 详细信息

特征基函数法是分析目标宽角度电磁散射特性的有效方法之一,但在构造特征基函数时,设置的入射波激励包含大量的冗余信息,大大降低了特征基函数的构造效率;另外在分析复杂目标时,在增加激励数目的情况下,仅应用主要特征基函数并不能显著提高计算精度。针对这些问题,该文对特征基函数构造方法进行改进,首先采用奇异值分解技术对激励矩阵进行压缩去除冗余信息,减少求解矩阵方程的次数;其次充分考虑子域之间的互耦作用,将主要特征基函数与次要特征基函数融合,得到改进的主要特征基函数。数值计算结果表明:与传统方法相比,该方法具有更高的计算效率和计算精度。

关键词：宽角度RCS 特征基函数法特征基函数奇异值分解

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