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Efficiency of sediment transport by flood and its control in the Lower Yellow River

Science china(Technological sciences) 2004年第Z1期47卷 173-185页

作者： NI Jinren1, LIU Xiaoyong2, LI Tianhong1, ZHAO Ye’an3 & JIN Ling1 1. Department of Environmental Engineering, Peking University the key laboratory of water and sedi- ment sciences, ministry of education, beijing 100871, china 2. General Institute of water Resources and Hydropower Planning and Design, ministry of water Re- sources, beijing 100011, china 3. The Yellow River Conservancy Commission, Zhengzhou 450003, china Department of Environmental Engineering Peking University Beijing China The key laboratory of water and sediment sciences Ministry of Education Beijing China General Institute of water Resources and Hydropower Planning and Design Ministry of Water Resources Beijing China The Yellow River Conservancy Commission Zhengzhou China

This paper presents the characteristics of sediment transport by flood in the Lower Yellow River with the reach from Huayuankou to Gaocun, which is regarded as a typical braided pattern. The Artificial Neural Network Model on water Use for sediment Transport (WUST) by flood was established based on the measured data from 1980 to 1998. Consequently, simulations of controlling process of sediment transport by flood were made in terms of the control theory under different scenarios. According to the situation of sediment transport by flood in the Lower Yellow River, Open-Loop control system and feedback control system were adopted in system design. In the Open-Loop control system, numerical simulations were made to reveal the relationship between average discharge of flood and the WUST with varying sediment concentrations. The results demonstrate that sediment concentration has significant influence on the controlling process of flood flow to WUST. It is practical and efficient to control WUST if sediment concentration is less than 20 kg/m3. In the feedback control system, controlling processes of sediment concentration and flood discharge for sediment transport were simulated respectively under given conditions, and it was found that sediment transport process could be controlled completely by sediment concentration and discharge at the inlet of the reach from Huayuankou to Gaocun. Using the same method, controlling processes of sediment transport by flood in other reaches in the Lower Yellow River were also simulated. For the case of sediment concentration being 20 kg/m3, the optimized controlling discharge ranges from 2390 to 2900 m3/s in the lower reach of Huayuankou. This study is also of significance to flood control and flushing sediment in the Lower Yellow River with proper operation modes of Xiaolangdi Reservoir.

关键词： the Lower Yellow River, flood, sediment transport, efficiency, simulation, control.

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On the variation of water resource structure in the Lower Yellow River

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Science china(Technological sciences) 2004年第Z1期47卷 127-141页

作者： NI Jinren1, WANG Yudong1, QIAN Zhenghan1, LI Tianhong1 & ZHAO Yean2 1. Department of Environmental Engineering, Peking University the key laboratory of water and sedi- ment sciences, ministry of education, beijing 100871, china 2. Institute of Hydraulic Research, Yellow River Conservancy Commission, Zhengzhou 450003, china Department of Environmental Engineering Peking University Beijing China The key laboratory of water and sediment sciences Ministry of Education Beijing China Institute of Hydraulic Research YellowRiver Conservancy Commission Zhengzhou China

In view of river functions and the Minimum water Demand for River Ecosystem (MWDRE), the water resources in the Lower Yellow River is further divided into three portions, i.e. water available for ecosystem (WE), water exploitable for socioeconomic purposes (WS) and excess flood water (WF). Corresponding conceptions and practical significances are expounded in details. The annual amount of the three portions of water resources from 1950 to 2001 is worked out on the basis of the daily hydrologic data, and the division of different portions is discussed. The results indicate that although the essential water demand for river functions is considered preferentially, the amount of the WE has decreased dramatically while its proportion increased gradually since the 1950s, and the shortage to the MWDRE increased markedly; both the amount and the proportion of the WS decreased notably. Since the 1990s, the actual water consumption for socioeconomic purposes in the lower reaches of the river basin has already exceeded the maximum amount of the WS and has to take over the WE which is already insufficient, hence not only the normal river functions are further disturbed and the river course shrinks greatly, but also the proportion and potential danger of the WF show no decreasing tendency in spite of the sharp decrease of upstream runoff.

关键词： the Yellow River, water resource structure, water available for ecosystem, water exploitable for socioeconomic purposes, excess flood water.

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利用GPS进行切沟侵蚀监测研究

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水土保持学报 2004年第5期18卷 91-94页

作者：游智敏伍永秋刘宝元北京师范大学沙漠与沙区资源研究所北京师范大学地理与遥感科学学院北京100875

切沟侵蚀在土壤侵蚀中占据重要位置,切沟侵蚀监测研究是切沟侵蚀研究的重要方面。目前进行切沟侵蚀监测研究主要利用摄影测量的方法,该方法存在一定的局限性。对利用GPS进行切沟侵蚀监测研究进行了探讨,对切沟在不同时间进行测量,获得... 详细信息

切沟侵蚀在土壤侵蚀中占据重要位置,切沟侵蚀监测研究是切沟侵蚀研究的重要方面。目前进行切沟侵蚀监测研究主要利用摄影测量的方法,该方法存在一定的局限性。对利用GPS进行切沟侵蚀监测研究进行了探讨,对切沟在不同时间进行测量,获得多个时相的DEM,通过对比不同时相的DEM来获取该时间段的切沟侵蚀变化。最后以位于黑龙江省漫川漫岗黑土区的丰产电流域的一条切沟为研究实例,建立了2002,2003年10月两个时段分辨率为0.4 m的DEM,对比这两个时段的数据表明,该切沟沟头后退达13.78 m,侵蚀面积增大了711m^2,切沟的土壤侵蚀量增加了2377 m^3,展示了GPS在切沟侵蚀研究中精度高、速度快等优越性,可为切沟侵蚀监测研究提供参考。

关键词： GPS 切沟侵蚀监测土壤侵蚀精度

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Feasibility and physics potential of detecting ^(8)B solar neutrinos at JUNO

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Chinese Physics C 2021年第2期45卷 93-110页

作者： Angel Abusleme Thomas Adam Shakeel Ahmad Sebastiano Aiello Muhammad Akram Nawab Ali Fengpeng An Guangpeng An Qi An Giuseppe Andronico Nikolay Anfimov Vito Antonelli Tatiana Antoshkina Burin Asavapibhop João Pedro Athayde Marcondes de André Didier Auguste Andrej Babic Wander Baldini Andrea Barresi Eric Baussan Marco Bellato Antonio Bergnoli Enrico Bernieri David Biare Thilo Birkenfeld Sylvie Blin David Blum Simon Blyth Anastasia Bolshakova Mathieu Bongrand Clément Bordereau Dominique Breton Augusto Brigatti Riccardo Brugnera Riccardo Bruno Antonio Budano Max Buesken Mario Buscemi Jose Busto Ilya Butorov Anatael Cabrera Hao Cai Xiao Cai Yanke Cai Zhiyan Cai Antonio Cammi Agustin Campeny Chuanya Cao Guofu Cao Jun Cao Rossella Caruso Cédric Cerna Jinfan Chang Yun Chang Pingping Chen Po-An Chen Shaomin Chen Shenjian Chen Xurong Chen Yi-Wen Chen Yixue Chen Yu Chen Zhang Chen Jie Cheng Yaping Cheng Alexander Chepurnov Davide Chiesa Pietro Chimenti Artem Chukanov Anna Chuvashova Gérard Claverie Catia Clementi Barbara Clerbaux Selma Conforti Di Lorenzo Daniele Corti Salvatore Costa Flavio Dal Corso Christophe De La Taille Jiawei Deng Zhi Deng Ziyan Deng Wilfried Depnering Marco Diaz Xuefeng Ding Yayun Ding Bayu Dirgantara Sergey Dmitrievsky Tadeas Dohnal Georgy Donchenko Jianmeng Dong Damien Dornic Evgeny Doroshkevich Marcos Dracos Frédéric Druillole Shuxian Du Stefano Dusini Martin Dvorak Timo Enqvist Heike Enzmann Andrea Fabbri Lukas Fajt Donghua Fan Lei Fan Can Fang Jian Fang Marco Fargetta Anna Fatkina Dmitry Fedoseev Vladko Fekete Li-Cheng Feng Qichun Feng Richard Ford Andrey Formozov Amélie Fournier Haonan Gan Feng Gao Alberto Garfagnini Alexandre Göttel Christoph Genster Marco Giammarchi Agnese Giaz Nunzio Giudice Franco Giuliani Maxim Gonchar Guanghua Gong Hui Gong Oleg Gorchakov Yuri Gornushkin Marco Grassi Christian Grewing Maxim Gromov Vasily Gromov Minghao Gu Xiaofei Gu Yu Gu Mengyun Guan Nunzio Guardone Maria Gul Cong Guo Jingyuan Guo Wanlei Guo Xinheng Guo Yuhang Guo Paul Hackspacher Caren Hagner Ran Han Yan Yerevan Physics Institute YerevanArmenia UniversitéLibre de Bruxelles BrusselsBelgium Universidade Estadual de Londrina LondrinaBrazil Pontificia Universidade Catolica do Rio de Janeiro RioBrazil Pontificia Universidad Católica de Chile SantiagoChile Universidad Tecnica Federico Santa Maria ValparaisoChile beijing Institute of Spacecraft Environment Engineering BeijingChina beijing Normal University BeijingChina china Institute of Atomic Energy BeijingChina Institute of High Energy Physics BeijingChina North china Electric Power University BeijingChina School of Physics Peking UniversityBeijingChina Tsinghua University BeijingChina University of Chinese Academy of sciences BeijingChina Jilin University ChangchunChina College of Electronic Science and Engineering National University of Defense TechnologyChangshaChina Chongqing University ChongqingChina Dongguan University of Technology DongguanChina Jinan University GuangzhouChina Sun Yat-Sen University GuangzhouChina Harbin Institute of Technology HarbinChina University of Science and Technology of china HefeiChina The Radiochemistry and Nuclear Chemistry Group in University of South china HengyangChina Wuyi University JiangmenChina Shandong University JinanChina Institute of Modern Physics Chinese Academy of SciencesLanzhouChina Nanjing University NanjingChina Guangxi University NanningChina East china University of Science and Technology ShanghaiChina School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghaiChina Tsung-Dao Lee Institute Shanghai Jiao Tong UniversityShanghaiChina Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesShijiazhuangChina Nankai University TianjinChina Wuhan University WuhanChina Xi’an Jiaotong University Xi’anChina Xiamen University XiamenChina School of Physics and Microelectronics Zhengzhou UniversityZhengzhouChina Institute of Physics National Chiao-Tung University Hsinchu National United University Miao-Li Department of Physics National T

The Jiangmen Underground Neutrino Observatory(JUNO)features a 20 kt multi-purpose underground liquid scintillator sphere as its main *** of JUNO's features make it an excellent location for^8B solar neutrino measurements,such as its low-energy threshold,high energy resolution compared with water Cherenkov detectors,and much larger target mass compared with previous liquid scintillator *** this paper,we present a comprehensive assessment of JUNO's potential for detecting^8B solar neutrinos via the neutrino-electron elastic scattering process.A reduced 2 MeV threshold for the recoil electron energy is found to be achievable,assuming that the intrinsic radioactive background^(238)U and^(232)Th in the liquid scintillator can be controlled to 10^(-17)g/*** ten years of data acquisition,approximately 60,000 signal and 30,000 background events are *** large sample will enable an examination of the distortion of the recoil electron spectrum that is dominated by the neutrino flavor transformation in the dense solar matter,which will shed new light on the inconsistency between the measured electron spectra and the predictions of the standard three-flavor neutrino oscillation *** m^(2)_(21)=4.8times10^(-5);(7.5times10^(-5))eV^(2),JUNO can provide evidence of neutrino oscillation in the Earth at approximately the 3sigma(2sigma)level by measuring the non-zero signal rate variation with respect to the solar zenith ***,JUNO can simultaneously measureDelta m^2_(21)using^8B solar neutrinos to a precision of 20% or better,depending on the central value,and to sub-percent precision using reactor antineutrinos.A comparison of these two measurements from the same detector will help understand the current mild inconsistency between the value of Delta m^2_(21)reported by solar neutrino experiments and the KamLAND experiment.

关键词： neutrino oscillation solar neutrino JUNO

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