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Science china(Technological Sciences) 2011年第S1期54卷 54-63页

作者： LI RuoNan 1,CHEN QiuWen 1,2 & Duan Chen 1,3 1 research Center for Eco-environmental Science,Chinese Academy of Sciences,Beijing 100085,china 2 china Three Gorges University,Yichang 443002,china 3.hydraulics department,changjiang river scientific research institute,wuhan 43.010,china 1. research Center for Eco-environmental Science Chinese Academy of Sciences Beijing 100085 China 2. china Three Gorges University Yichang 443002 China 3. hydraulics department Changjiang River Scientific Research Institute Wuhan 430010 China

Hydropower development changes the river hydrological regime,thereby altering river ecosystem *** important measure for reducing degradation of ecosystem is to determine ecological flow and implement it by reservoir *** paper described a method to calculate river ecological flow based on fish habitat conservation and applied it to Jinping river Bend of Yalong *** chongi was selected as target species,and the fish habitat model coupling with water environmental model was developed according to the relationship between fish and water environment ***,improved hydraulic habitat suitability index(IHHS) and habitat fragment index(HFI) varying with discharge were discussed in this *** area representing average annual flow was taken as a reference,and then ecological hydrographs under different habitat conservation levels were calculated considering season variation and life stages of *** to the natural condition,the model results indicated that the reservoir operation clearly influenced the habitat of the target *** was proposed to ensure flow releases to maintain 70%-90% habitat in section after joint while about 60% before joint.

关键词： river habitat habitat assessment ecological flow ecological hydrograph

EXPERIMENTAL STUDIES ON FREQUENCY CHARACTERISTICS OF THE FLUCTUATING PRESSURE ACTING ON THE APRON OF STILLING BASINS WITH LOW FROUDE NUMBER

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Journal of Hydrodynamics 1992年第4期4卷 21-26页

作者： Ding Zhuo-yi Yangtze river scientific research institute,wuhan Hubei 43.010,P.R.china Yangtze river scientific research Inst Wuhan China

Using four types of stilling basin models,this paper studies frequency characteris- tics of the fluctuating pressure acting on the stilling basin apron when Froude number is not greater than *** testing results show that the frequency of fluctuating pressure,f_s in the ranges of 0. 4Hz≤f_s≤1.1Hz.0.2Hz≤f_s≤2.5Hz and 0.4Hz≤f_s≤*** be used as the design frequency corresponding to three patterns of hydraulic *** reliability of f_s for three jump patterns is all nearly equal to 90%.

关键词： frequency characteristics fluctuating pressure stilling basin apron

A 2-D HYDRODYNAMIC MODEL FOR THE river,LAKE AND NETWORK SYSTEM IN THE JINGJIANG REACH ON THE UNSTRUCTURED QUADRANGLES

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Journal of Hydrodynamics 2010年第3期22卷 419-429页

作者： ZHANG Xi-bing HU De-chao WANG Min State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan430072 China Yangtze river scientific research institute Wuhan 430010 China State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China

The main river, the Dongting Lake and river networks in the Jingjiang reach of the Yangtze river constitute a complex water system, for which a full 2-D hydrodynamic model is established instead of the traditional 1-D or compound models for simulation of such complex systems, based on the latest developments of computer technologies and numerical methods. To better handle irregular boundaries and keep the computation cost well in a reasonable limit, unstructured grids of moderate scale are used. In addition, a dynamic boundary tracking method is proposed to simulate variable flow domains at different floods, especially, when the moderate scale gird can not describe flows in narrow river-network channels at low water levels. The t9 semi-implicit method and the Eulerian-Lagrangian Method （ELM） are adopted, which make the model unconditionally stable with respect to the gravity wave speed and Courant number restrictions. Properties and efficiency of the model are discussed, and it is concluded that the new model is robust and efficient enough for the simulation of a big, complex water system. Validation tests show that the simulation results agree well with field data. It takes about 0.96 h to complete the computation of a 76 d flood, which indicates that the model is efficient enough for engineering applications.

关键词： 2-D numerical model river network unstructured grid semi-implicit Eulerian-Lagrangian Method (ELM) boundarytracking

Anti-Crack Performance of Low-Heat Portland Cement Concrete

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Journal of wuhan University of Technology(Materials Science) 2007年第3期22卷 555-559页

作者：杨华全 changjiang river scientific research institute

The properties of low-heat Portland cement concrete（LHC） were studied in detail. The experimental results show that the LHC concrete has characteristics of a higher physical mechanical behavior, deformation and durability. Compared with moderate-heat Portland cement（MHC）, the average hydration heat of LHC concrete is reduced by about 17.5%. Under same mixing proportion, the adiabatic temperature rise of LHC concrete was reduced by 2 ℃-3 ℃,and the limits tension of LHC concrete was increased by 10× 10^-6-15×10^-6 than that of MHC. Moreover, it is indicated that LHC concrete has a better anti-crack behavior than MHC concrete.

关键词： low-heat portland cement mass concrete high crack resistance moderate-heat portland cement

2－D　SIMULATION　OF　OPEN　CHANNEL　TURBULENT　FLOW　WITH　HIGH　REYNOLDS　NUMBER　BY　EMPLOYING　N－S　EQUATIONS　AND　IEM

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Journal of Hydrodynamics 1996年第1期8卷 44-51页

作者： Wang Ding-yang Liu He-dong(Yangtze river scientific research institute, wuhan 43.010, P. R. china) Yangtze river scientific research Inst Wuhan China

Since 1986, we have been studying the topic of simulating open channel turbulent flow, especially the back flow in extended section, by directly employing N-S equations. Now a breakthrough may be obtained. The simulat... 详细信息

关键词： turbulent flow open channel flow N-S equation.

A fusion algorithm for remote sensing images based on nonsubsampled pyramids and bidimensional empirical decomposition

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Science china(Technological Sciences) 2010年第S1期53卷 196-204页

作者： ZHANG XiaoDong 1,WANG WenBo 2,WANG DiFeng 3 & ZHANG Yu 4 1 State Key Laboratory of Information Engineering in Surveying,Mapping and Remote Sensing,wuhan University,wuhan 430079,china 2 College of Sciences,wuhan University of Science and Technology,wuhan 430065,china 3State Key Laboratory of Satellite Ocean Environment Dynamics,Second institute of Oceanography,State Oceanic Administration,Hangzhou 310012,china 4 Spatial Information Technology Application research institute,changjiang river scientific research institute,wuhan 43.010,china wuhan Univ State Key Lab Informat Engn Surveying Mapping & R Wuhan 430079 Peoples R China wuhan Univ Sci & Technol Coll Sci Wuhan 430065 Peoples R China State Ocean Adm Inst Oceanog 2 State Key Lab Satellite Ocean Environm Dynam Hangzhou 310012 Zhejiang Peoples R China changjiang river Sci Res Inst Spatial Informat Technol Applicat Res Inst Wuhan 430010 Peoples R China

In order to improve the quality of remote sensing image fusion,a new method combining nonsubsampled Laplacian pyramid (NLP)and bidimensional empirical mode decomposition(BEMD)is ***,the high resolution panchromatic image (PAN)is decomposed using NLP until the approximate component and the low resolution multispectral image(MS)contain features with a similar ***,the approximation component and the MS are decomposed by BEMD,resulting in a number of bidimensional intrinsic mode functions(BIMF)and a residue *** instantaneous frequency is computed in 4 directions of the *** the positive or negative coefficients in the corresponding position,a weighted algorithm is designed for fusing the high frequency details using the instantaneous frequency and the coefficient absolute value of the BIMFs as fusion *** fused image is then obtained through inverse BEMD and *** results have illustrated the advantage of this method over the IHS,DWT andà-Trous wavelet in both spectral and spatial detail qualities.

关键词： bidimensional empirical mode decomposition nonsubsampled pyramid instantaneous frequency remote sensing image fusion

Non-uniform sediment incipient velocity

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International Journal of Sediment research 2008年第1期23卷 69-75页

作者： Haitao XU1, Jinyou LU2, and Xiaobin LIU11 Master,Yangtze river scientific research Insitute, wuhan 43.010, china. 2 Prof., Yangtze river scientific research Insitute, wuhan 43.010, china [a]Master Yangtze river scientific research Insitute wuhan 43.010 china [b]Prof. Yangtze river scientific research Insitute wuhan 43.010 china

Based on the mechanism of non-uniform sediment incipient motion, the dragging force and uplift force coefficient expressions are put forward for the non-uniform bed material exposure and close alignment state. The incipient velocity formula of the non-uniform sediment is then established. It is shown that the formula structure is reasonable, and fine particles of the non-uniform sediment are more difficult to set into motion than the same sized uniform particles, whereas coarser particles are easier to set into motion than their uniform equivalents. The validity of the formula is verified by field and experiment data.

关键词： Non-uniform sediment motion Bed material distribution Incipient velocity

STUDIES ON PROPERTIES OF FLOW CAVITATION NUMBER AND MINIMUM PRESSURE COEFFICIENT IN SHORT CLOSED CONDUITS

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Journal of Hydrodynamics 1994年第3期6卷 1-6页

作者： Ding Zhuo-yiYangtze river scientific research institute, wuhan 43.010, P. R. china

For a short closed conduit with smooth (streamline pattern) boundary, the comparison of minimum pressure coefficient at boundary, - Cpm , which obtained from model tests, with flow cavitation number a is possible to describe the property of preventing cavitation in the closed conduit.In this paper, analytical results show that the ratio σ/ - Cpm decreases with increasing Reynolds number Re, when the configuration of the conduit is designed, and this ratio approaches a constant when Re = 106 or so. The model test data for five engineering cases of the short closed conduit with various configuration indicates that the analytical results are reliable. Therefore, the value of the ratio σ/ - Cpm corresponding to that of Reynolds number in model (Re)m ≥106 must be taken so as to correctly describe the cavitation property of the studied conduit. The condition of Lr ≥ 10-4[(Re)p]2/3 should be satisfied ( Lr is model length scale; (Re)p is Reynolds number in prototype) when the model is designed by Froude criterion of similarity.

关键词： cavitation number minimum pressure coefficient conduit.

Hydration Kinetics of Phosphorus Slag-cement Paste

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Journal of wuhan University of Technology(Materials Science) 2011年第1期26卷 142-146页

作者：陈霞 School of Civil Engineering Wuhan University department of Mateials and Structure Changjiang River Scientific Research lnstitute

Hydration characteristics of Portland cement paste with phosphorus slag powder incorporated and hydration kinetics was investigated with SEM, X-ray diffraction, DTA-TG and calorimeter Ⅱ80. Results showed that phosphorus slag powder could reduce total amount of hydration products yet had little influence on the type of hydration products. The total amount of heat of hydration was decreased by 49.11% and the final setting was postponed by 2.28 h when phosphorus slag powder substituted 35% Portland cement by mass. The accelerating stage of this composite paste was controlled by catalysis, decreasing stage controlled by both catalysis and diffusion while stabilizing stage by diffusion alone. Hydration resistance and activation energy were reduced and hydration speed was accelerated.

关键词： phosphorus slag hydration kinetics cement micro structure mechanism.

TURBULENT FLOWS AROUND SAND DUNES IN ALLUVIAL riverS

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Journal of Hydrodynamics 2010年第1期22卷 103-109页

作者： LIU Shi-he YIN Shu-ran GUO Wei College of Water Resource and Hydropower Wuhan University Wuhan 430072 China Yangtze river scientific research institute Wuhan 430010 China

The sand dunes are typical bed forms of natural alluvial rivers. In this article, a vertical 2-D Reynolds stress model is established for the simulation of turbulent flows around sand dunes, and water-sand boundary conditions are set with particular attention. By numerical simulations, the following conclusions can be drawn. （1） The flow resistance in rivers with sand dunes could be divided into the sand-grain resistance and the sand dune resistance, and the sand-grain resistance coefficient mainly depends on Reynolds number, relative sand grain roughness and sand dune steepness. This coefficient in rivers with sand dunes would be larger than that calculated in a flat riverbed, and the steeper the sand dunes, the larger the sand-grain resistance coefficient. （2） The sand dune resistance coefficient mainly depends on the relative sand dune height and sand dune steepness, the steeper the sand dunes, the larger the sand dune resistance coefficient. （3） For the flat riverbed, the turbulent eddy viscosity coefficient and the sediment diffusion coefficient are approximately identical, but for the sand dune riverbed, in the vertical position, where the sediment diffusion coefficient reaches its maximum, it would be higher than the turbulent eddy viscosity coefficient.

关键词： sand dune flow resistance sediment diffusion coefficient eddy viscosity