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关于黄河流域生态保护和高质量发展的思考

人民黄河 2024年第9期46卷 1-7页

作者：张楚汉王光谦清华大学水圈科学与水利工程全国重点实验室北京100084

黄河是中华民族的母亲河,黄河流域是重要的生态屏障和经济带,也是重要的粮食和能源基地,对我国政治、经济和文化发展具有不可替代的重要作用,黄河流域生态保护和高质量发展已上升为一项重大国家战略。黄河又是世界上最为复杂难治的河流... 详细信息

黄河是中华民族的母亲河,黄河流域是重要的生态屏障和经济带,也是重要的粮食和能源基地,对我国政治、经济和文化发展具有不可替代的重要作用,黄河流域生态保护和高质量发展已上升为一项重大国家战略。黄河又是世界上最为复杂难治的河流之一,我国治理黄河历史悠久,人民治黄以来,黄河流域治理和生态保护取得了举世瞩目的成就,但仍面临诸多亟待解决的重大问题。梳理了人民治黄的辉煌成就,分析了当前治黄面临的形势与挑战,并针对如何实现黄河流域长治久安与高质量发展提出了构建流域水资源保障体系、实现流域重点地区生态环境修复与保护、完善流域防洪防凌与水沙调控工程体系等对策建议。

关键词：生态保护高质量发展黄河流域

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清嘉定进士王元勳研究

上海地方志 2024年第1期 65-73,94页

作者：王光乾上海市嘉定博物馆上海201899

本文综合运用方志、诗文集、家谱、诗札等传世文献和文物,钩沉发覆,考探嘉定乡贤、乾隆四十三年(1778)进士、徐州府教授、著名诗人王元勳的门第和科途、诗业和著作、师友和弟子,以期弥补史乘记载之疏略,较完整地勾勒出其一生履历和行迹... 详细信息

本文综合运用方志、诗文集、家谱、诗札等传世文献和文物,钩沉发覆,考探嘉定乡贤、乾隆四十三年(1778)进士、徐州府教授、著名诗人王元勳的门第和科途、诗业和著作、师友和弟子,以期弥补史乘记载之疏略,较完整地勾勒出其一生履历和行迹,并还原其某些具体的生活片段。

关键词：王元勳嘉定清朝家世生平

PVA-ECC高温冷却后力学特性与微观损伤机理

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哈尔滨工业大学学报 2024年第9期56卷 140-149页

作者：武芳文何岚清段钧淇王广倩刘来君杨飞长安大学公路学院西安710064 长安大学建筑工程学院西安710061

为研究工程水泥基复合材料(engineered cementitious composite,ECC)高温后的力学性能和微观特征,对ECC进行了高温后材料力学性能试验和微观特征观测。对常温(25℃)、200℃、300℃、400℃及500℃自然冷却和喷水冷却后的ECC试件开展了抗... 详细信息

为研究工程水泥基复合材料(engineered cementitious composite,ECC)高温后的力学性能和微观特征,对ECC进行了高温后材料力学性能试验和微观特征观测。对常温(25℃)、200℃、300℃、400℃及500℃自然冷却和喷水冷却后的ECC试件开展了抗压和抗折性能试验,并结合扫描电镜分析了ECC微观结构损伤特征以及探究了ECC高温后损伤机理。实验结果表明:高温后ECC表面未发生剥落,500℃以内未见爆裂现象,随着温度升高,纤维由混凝土表面逐渐向内部熔化,且失水增多,最大烧失率13.9%;力学性能方面,ECC自然冷却后抗压强度随温度升高呈现先降低后升高再降低的现象,而喷水冷却后抗压强度随温度的升高单调降低,且强度降低显著;高温后抗折强度随温度升高逐步下降,自然冷却降低幅度较喷水冷却显著;结合微观结构变化,ECC经历高温时,纤维部分熔化导致纤维与基体的黏结性能减弱;随着温度升高水化产物之间逐渐呈现独立存在的分散体,但喷水冷却后未水化颗粒二次水化现象明显,使ECC抗折强度较自然冷却提升17%。ECC具有良好的热稳定性,且冷却方式影响ECC材料的表观特性、力学性能和微观特征。

关键词：桥梁工程力学特性高温试验 ECC 微观结构冷却方式

Fluvial Processes in the Meandering Reach of the Lower Wei River During the Course of Degradation

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四川大学学报（工程科学版） 2005年第S1期37卷 46-51页

作者： Xia, Junqiang wang, guangqian Wu, Baosheng Dept. of Hydraulic Eng. Tsinghua Univ. Beijing 100084 China

This paper presents an analysis of the changes of the longitudinal and lateral profiles in the meander- ing reach of the Lower Wei River over the period from October 1973 to October 1976 during the course of *** results indicated that retrogressive erosion and subsequent downstream erosion occurred in the reach due to the lowering in the Tongguan elevation and the inflowing water carrying low sediment con- *** the end of the degradation,the main channel widths of the majority ...

关键词： the Lower Wei River fluvial processes batse level of erosion channel widening channel undercut

Design and evaluation of control systems for a real canal

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Science China(Technological Sciences) 2012年第1期55卷 142-154页

作者： SHANG YiZi ROGERS Peter wang guangqian State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China School of Engineering andApplied Science Harvard University Boston 02138 U.S.A.

The distant downstream proportional integral(PI) feedback control was applied to the W-M lateral canal of the Maricopa Stanfield Irrigation and Drainage District located in central Arizona,*** configuration of those controls for the ca-nal can be *** this end,an integrated approach to the design of an automatic control system for the canal was *** approach presented herein is not only a systematical review of previous work,but also represents a further ad-vance of the previous simulation study by Tsinghua University(Shang et al,2011) on relating the canal control algorithm to local PI controls for the real *** evaluate the control system potential,performance of the control algorithm that was ob-tained through implanting predicative module into linear quadratic regulator(LQR) was analyzed with singular value *** "manufactured" tests were conducted to compare with the control system that is currently in *** results indi-cated that the developed control system rather than the system in current use had considerable potential to closely match dis-charge at the downstream check structures with those ordered by water users while maintaining the water level throughout the length of the canal.

关键词： canal control system singular value bode proportional integral (PI) control linear quadratic regulator (LQR)

Two-dimensional numerical modeling of the longitudinal and lateral channel deformations in alluvial rivers

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Science China(Technological Sciences) 2004年第Z1期47卷 199-211页

作者： XIA Junqiang wang guangqian WU Baosheng Department of Hydraulic Engineering Tsinghua University Beijing 100084 China Department of Hydraulic Engineering Tsinghua University Beijing 100084 China Department of Hydraulic Engineering Tsinghua University Beijing 100084 China

Two kinds of bank erosion mechanisms were analyzed, including fluvial and non-fluvial controlled mechanisms, and mechanical methods of simulating the erosion processes of cohesive, non-cohesive and composite riverbanks were improved. Then a two-dimensional numerical model of the channel deformation was developed, consisting of a 2D flow and sediment transport submodel and bank-erosion submodels of different soil riverbanks. In the model, a new technique for updating the bank geometry during the bed evolution was presented, which combines closely two kinds of submodels. The proposed model is capable of not only predicting the processes of flood routing and longitudinal channel deformation in natural rivers, but also simulating the processes of lateral channel deformation, especially the processes of lateral erosion and failure of cohesive, non-cohesive and composite riverbanks.

关键词： soil riverbanks, bank erosion, longitudinal channel deformation, lateral channel deformation, 2D numerical model.

Numerical simulation of ae-olian sediment transport

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Chinese Science Bulletin 2001年第9期46卷 786-789页

作者： Qicheng Sun guangqian wang Tsing Hua Univ Dept Hydraul Engn Beijing 100084 Peoples R China

A discrete element model (DEM) is developed for aeolian sediment transport in the scope of investigation of the dynamic behavior of grains, in which the motion of individual grain is considered while velocity distribution of wind is given according to bed forms. The above model has been used for simulating the phenomenon of 4000 grains blown by wind, resulting in ripples and saltating paths, which shows good agreements with experimental observations. The result is helpful for revealing the intrinsic mechanism of sand flow.

关键词： aeolian sediment transport desertification discrete element model numerical simulation.

A physics-based hydro-geomorphologic simulation utilizing cluster parallel computing

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Science China(Technological Sciences) 2013年第8期56卷 1883-1895页

作者： RAN QiHua SU DanYang FU XuDong wang guangqian Department of Hydraulic Engineering Zhejiang University Department of Earth Ocean and Atmospheric SciencesUniversity of British ColumbiaVancouverBCV6T 1Z4Canada State Key Laboratory of Hydroscience and Engineering Tsinghua University

To conduct a large-scale hydrologic-response and landform evolution simulation at high resolution,a complex physics-based numerical model,the Integrated Hydrology Model(InHM),was revised utilizing cluster parallel *** parallelized InHM(ParInHM) divides the simulated area into multiple catchments based on geomorphologic features,and generates boundary-value problems for each catchment to construct simulation tasks,which are then dispatched to different computers to start the *** evolution is considered during simulating and implemention in one *** dynamical Longest-Processing-Time(LPT) first scheduling algorithm is applied to job *** addition,a pause-integratedivide-resume routine method is used to ensure the hydrologic validity during the simulation *** routine repeats until the entire simulation period is *** has been tested in a computer cluster that uses 16 processors for the calculation,to simulate 100 years' hydrologic-response and soil erosion for the 117-km2 Kaho'olawe Island in the Hawaiian Islands under two different mesh *** efficiency of ParInHM was evaluated by comparing the performance of the cluster system utilizing different numbers of processors,as well as the performance of non-parallelized system without domain *** results of this study show that it is feasible to conduct a regional-scale hydrologic-response and sediment transport simulation at high resolution without demanding significant computing resources.

关键词： Integrated Hydrology Model(InHM) parallelized InHM(ParInHM) physics-based hydrological model hydro-geomorphologic simulation parallel computing numerical simulation

The quantization of river network morphology based on the Tokunaga network

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Science China Earth Sciences 2009年第11期52卷 1724-1731页

作者： Li Zhang BinXiang Dai guangqian wang TieJian Li Hao wang School of Mathematical Sciences and Computing Technology Central South University Changsha 410075 China State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China

River network morphology not only reflects the structure of river stream but also has great effects on hydrological process, soil erosion, river evolution, and watershed topography. Here we propose and define a new sequence of self-similar networks and corresponding parameters for the generated Tokunaga network. We also discuss the topological and numerical characteristics of self-similar networks with different iteration rules by utilizing links and fractal dimension. Application results indicate that the proposed method could be used to generate river network, which is much consistent with natural river network. The proposed parameter λ could well reflect the river network morphology.

关键词： fractal dimension river network morphology Tokunaga network