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

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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{2. and {2., Ministry of Water Re- sources, Beijing 100011, China 3. The Yellow River Conservancy Commission,{3., China 1. Department of Environmental Engineering Peking University 100871 Beijing China 2. The Key Laboratory of Water and Sediment Sciences Ministry of Education 100871 Beijing China 3. General institute of Water Resources and Hydropower{2. and {2. Ministry of Water Resources 100011 Beijing China 4. The Yellow River Conservancy Commission 450003 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 2. 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 2. kg/m3. the optimized controlling discharge ranges from 2.1}0 to 2.00 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.

Response of flood discharging capacity to the deterioration of the lower Yellow River

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Science China(Technological Sciences) 2004年第z1期47卷 152-160页

作者： LI Wenxue1, LI Yong2. YAO Wenyi2. SU Yunqi2.& ZHANG Xiaohua2.1. Yellow River Engineering Consulting Co. Ltd., zhengzhou 450003, China 2. Yellow River institute of Hydraulic {2., zhengzhou 450003, China Yellow River Engn Consulting Co Ltd Zhengzhou 450003 Peoples R China Yellow River Inst Hydraul Res Zhengzhou 450003 Peoples R China

Based on the clarifications of the deterioration characteristics of the lower Yellow River (LYR), the influence of river deterioration on flood discharging capacity is studied through theoretical derivation and analysis of field data. This study indicates that response of flood discharging capacity to river deterioration is nonlinear. Sediment depositions in the main channel cause the reductions of dominant discharge and thus the increase of initial flood stage. Reductions in the channel width result in the increases of the rising rate of flood stage and the decrease of flood discharging capacity.

关键词： flood discharging capacity, boundary condition, deterioration, sediment, the lower Yellow River.

A distributed hydrological model with its application to the Jinghe watershed in the Yellow River Basin

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Science China(Technological Sciences) 2004年第z1期47卷 60-71页

作者： WANG Zhonggen1, ZHENG Hongxing1, LIU Changming1, , WU Xianfeng2.2.& ZHAO Weimin3.1. Key Laboratory of Water Cycle & Related Land Surface Processes, institute of Geographic Science and Natural Resources {2., Chinese Academy of Sciences, Beijing 100101, China 2. institute of Environmental Science, Beijing Normal University, Beijing 100875, China 3. Water Resources Conservation Committee of Yellow River,{3., China Chinese Acad Sci Key Lab Water Cycle & Related Land Surface Proc Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China Beijing Normal Univ Inst Environm Sci Beijing 100875 Peoples R China Water Resources Conservat Comm Yellow River Zhengzhou 450003 Peoples R China

For the purpose of water resources management in the Yellow River Basin with highly spatial difference, a daily distributed hydrological model was proposed, of which the determination of spatially-distributed parameters and model inputs processing were performed by means of GIS/RS. In the model, the computation of runoff yield was based on the topography index method and flow routing was modeled by Maskingum method. The operation of the model is followed by means of “command structure” technique based upon the topography of river network. A case study using the model was conducted for the Jinghe watershed, which locates at the middle Yellow River Basin. The simulation of the hydrological processes in 1996 has shown that water quantity balance errors were less than 5% and the Nash-Sutcliffe coefficient arrived at 0.7, indicating that the model structure is justifiable, and the precision of the model can satisfy the purpose of water resources management.

关键词： distributed hydrological model, structure and equation, GIS and RS, Jinghe Basin, Yellow River Basin.

Main chemical ingredients of the celadon glaze from Qingliangsi kiln and Zhanggongxiang kiln

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Science China(Physics,Mechanics & Astronomy) 2006年第4期49卷 487-495页

作者： ZHAO Weijuan1, LU Xiaoke1, LI Guoxia1, GUO Min1, XIE Jianzhong1, GAO Zhengyao1, SUN Xinmin2. GUO Musen2. CHENG Huansheng3.& ZHANG Bin3.1. Faculty of Physical Engineering, {2. University, {2. 450052. China 2. {2. {3. of Cultural Relic and Archaeology, Henan Province, {2. 450004, China 3. {2. {3. of Modern Physics, Fudan University, Shanghai 2.043., China 1. Faculty of Physical Engineering Zhengzhou University Zhengzhou 450052 China 2. research institute of Cultural Relic and Archaeology Henan Province Zhengzhou 450004 China 3. research {2. of Modern Physics Fudan University Shanghai 200433 China

The proton induced X-ray emission (PIXE) is used to determine the chemical ingredients of seven main elements in the samples of Ru Guan porcelain glazes and Ru Civil porcelain from Qingliangsi kiln in Baofeng County and the samples of celadon glaze from Zhanggongxiang kiln in Ruzhou City. The PIXE data are then analyzed by scatter analysis and fuzzy cluster method for determining their classification and provenance. The results show that there are obvious differences between the ingredients of glaze material of Ru Guan porcelain and Ru Civil porcelain from Qingliangsi kiln, of which the former ingredients are stable and its source is localized, and that the sources and ingredients of the glaze of Ru Guan porcelain and those of celadon glaze from Zhanggongxiang kiln are not wholly the same, of which the latter sources are much scattering.

关键词： Zhanggongxiang kiln, Qingliangsi kiln, the source of raw material, the proton induced X-ray emission.

LONG AND DEEP DIVERSION TUNNELS OF 1^(ST) STAGE PROJECT IN WEST ROUTE OF SOUTH-NORTH WATER TRANSFER PROJECT

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岩石力学与工程学报 2003年第9期22卷 1527-1532页

作者： Shen Fengsheng,Liu Xin (reconnaissance,planning,{2. and {3. institute,Yellow River Construction Commission, Ministry of Water Resources, zhengzhou 450003 China) reconnaissance Planning Design and Research Institute Yellow River Construction Commission Ministry of Water Resources Zhengzhou 450003

West Route of South-North Water Transfer Project,situated in southeastern Qinghai-Tibet Plateau,is a giant project,which will deliver 17 billion m3.of water from the main stream and tributaries upstream of the Yangtze River to the upper reaches of the Yellow River. It is to be constructed in 3.stages, of which the 1st stage project includes delivering 4 billion m3.of water by gravity from two tributaries of Yalong River and three tributaries of Dadu River. The project consists of 5 dams,7 tunnels and a channel in series,with the dam height of 63.12.0}m and water transfer length of 2.0.3.km,of which the tunnels measure 2.4.1 km. The special climatic,environmental and geologic conditions make the project much more complicated in construction,especially 3.tunnels with the length longer than 50 km each create challenges to the technical requirements of engineering survey,design and construction.

关键词：南水北调工程西线工程引水隧洞 TBM

design and verification of an FPGA programmable logic element based on Sense-Switch pFLASH

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Frontiers of Information Technology & Electronic Engineering 2024年第4期25卷 485-499页

作者： zhengzhou CAO Guozhu LIU Yanfei ZHANG Yueer SHAN Yuting XU No.58 research institute China Electronics Technology Group CorporationWuxi 214035China

This paper proposes a kind of programmable logic element(PLE)based on Sense-Switch pFLASH *** programming Sense-Switch pFLASH,all three-bit look-up table(LUT3.functions,partial four-bit look-up table(LUT4)functions,latch functions,and d flip flop(DFF)with enable and reset functions can be *** PLE uses a choice of operational logic(COOL)approach for the operation of logic functions,it allows any logic circuit to be implemented at any ratio of combinatorial logic to *** intrinsic property makes it close to the basic application specific integrated circuit(ASIC)cell in terms of fine granularity,thus allowing ASIC-like cell-based mappers to apply all their optimization *** measuring Sense-Switch pFLASH and PLE circuits,the results show that the“on”state driving current of the Sense-Switch pFLASH is about 2.5.52.A,and that the“off”state leakage current is about 0.1 *** programmable function of PLE works *** delay of the typical combinatorial logic operation AND3.is 0.69 ns,and the delay of the sequential logic operation DFF is 0.65 ns,both of which meet the requirements of the {2. technical index.

关键词： Field programmable gate array(FPGA) Programmable logic element(PLE) Boolean logic operation Look-up table Sense-Switch pFLASH Threshold voltage

Combined adjustment project of national astronomical geodetic networks and 2.00' national GPS control network

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Progress in Natural Science:Materials International 2005年第5期15卷 435-441页

作者： YANG Yuanxi1*, ZHA Ming2. SONG Lijie3. WEI Ziqing1, WANG Zhouping2. OUYANG Guichong2. XU Bilin2. WU Xiaoping3.and WANG Junqin4(1. Xi'an {2. institute of Surveying and Mapping, Xi'an 710054, China 2. Xi'an Informational and Technical Center of Surveying and Mapping, Xi'an 710054, China 3. {2. institute of Surveying and Mapping, {2. 450052. China 4. The First Surveying Team of Tianjin, Tianjin 3.0140, China) Xian research institute of Surveying and Mapping Xi''an 710054 China Xi''an Informational and Technical Center of Surveying and Mapping Xi''an 710054 China zhengzhou institute of Surveying and Mapping Zhengzhou 450052 China

The combined adjustment project of the nationwide astronomical geodetic networks and 2.00' national GPS control network involve 48519 terrestrial observational stations and 2.66 GPS observational stations. In the terrestrial network, 2.107 stations are height fixed and 2.0}12.stations are in three dimensions. 440793.terrestrial observations and 183.68 unknowns are involved in the adjustment. The three-dimensional observational models for the adjustment have been established. The crustal deformation influences and corrections are researched. Fast methods of solving partitioned adjustment for super large-scale geodetic network have been studied. The standard deviations of three-dimensional coordinates for all stations are evaluated. As a result of the combined adjustment, a unified national geodetic network with nearly 50000 stations is established, the high accurate three-dimensional geocentric coordinates are obtained. The standard deviation for geoid is averagely 0.2.m, for vertical deflection is about 1.5″, for the horizontal position is about 0.12.m, for the geodetic height is about 0.14 m, and for the three-dimensional position is averagely 0.3.m.

关键词： astronomical geodetic network GPS network combined adjustment datum geocentric coordinates.

Effect of Initial Microstructure on Warm Deformation Behavior of 45 Steel

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Journal of Iron and Steel research International 2012年第8期19卷 75-78页

作者： ZHAO Xin1, YANG Xiao-ling2. JING Tian-fu3.(1. The Sixth Department, zhengzhou {2. of Aeronautics, zhengzhou 450015, Henan, China 2. zhengzhou Zhongxing Basic Constructions Development Co Ltd, zhengzhou 450015, Henan, China 3. State Key Laboratory of Metastable Materials Science and Technology, Qinhuangdao 066004, Hebei, China) [a] The Sixth Department Zhengzhou Institute of Aeronautics Zhengzhou 450015 Henan China [b] zhengzhou Zhongxing Basic Constructions Development Co Ltd Zhengzhou 450015 Henan China [c] State Key Laboratory of Metastable Materials Science and Technology Qinhuangdao 066004 Hebei China

In order to investigate the effect of initial microstructure on warm deformation behavior, some specimens of 45 steel were annealed and some quenched. Then the specimens were isothermally compressed on a Gleeble 3.00 machine. The deformation temperature range was 550 to 700 ℃ and the strain rate range was 0.001 to 0.1 s-1. An optical microscope (OM) and a transmission electron microscope (TEM) were used to study the microstructures. The results show that the microstructure of annealed specimens is ferrite and pearlite and that of quenched specimens is martensite. The flow stress of quenched specimens is higher than that of annealed ones at 550 ℃ when strain rates are greater than 0.001 s-1. However, at 600 to 700 ℃ and strain rate of 0.001 s-1, the whole flow curves of quenched specimens are below that of annealed ones. Under the rest conditions, the flow stress of quenched specimens is higher at the beginning of compression and then the opposite is true after the strain is greater than a critical value. The microstructure examination proves that the tempering and dynamic recrystallization easily occur in the specimens with martensite during warm compression, which results in the above phenomena.

关键词： warm deformation flow stress steel microstructure

Risk analysis model for landslide mass of high slope in dam area

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Science China(Technological Sciences) 2008年第S2期51卷 25-31页

作者： GU ChongShi1,2.HE XianFeng3.4,WU ZhongRu1,2.& SU HuaiZhi1,2.1 College of Water Conservancy and Hydropower Engineering,Hohai University,Nanjing 2.0098,China 2.National Engineering research Center of Water Resources Efficient Utilization and Engineering Safety,Nanjing 2.0098,China 3.Yellow River institute of Hydraulic research,{3. 450003,China 4 Embankment Security Defect Prevention and Control Engineering research Center of MWR,{3. 450003,China 1. College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China 2. National Engineering research Center of Water Resources Efficient Utilization and Engineering Safety Nanjing 210098 China 3. Yellow River institute of Hydraulic {2. Zhengzhou 450003 China 4. Embankment Security Defect Prevention and Control Engineering research Center of MWR Zhengzhou 450003 China

In order to identify the threat of reservoir bank landslide to dam safety and reduce the risk of dam failure,impact factors of the landslide are *** concept of landslide risk degree is put forward to measure the threat of landslide to dam *** monotony of the landslide risk assessment function which changes with different affecting factors is analyzed *** on gene automatic programming,a data mining model of the landslide risk assessment function is constructed combined with impact factors of reservoir bank landslide on dam *** the assessment function of landslide risk has been excavated and established according to practical project information,which provides a valuable reference for analyzing the impact of landslide on dam risk.

关键词： landslide dam failure risk landslide risk