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Jackson type theorems on complex curves

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Science china Mathematics 2009年第3期52卷 493-506页

作者： TU TianLiang Deptartment of Mathematics and Informatics, north china institute of water conservancy and hydroelectric power, zhengzhou 450011, china Deptartment of Mathematics and Informatics North China Institute of Water Conservancy and Hydroelectric Power Zhengzhou China

Let Γ be a closed smooth Jordan curve in the complex plane. In this paper, with the help of a class of fundamental functions of Hermite interpolation, the author introduces a continuous function interpolation which uniformly approximates to f(z) ∈ C(Γ ) with the same order of approximation as that in Jackson Theorem 1 on real interval [1, 1]. The accuracy of the order of approximation is proved. Using the method different from the early works, the author studies simultaneous approximation to function and its derivatives and the desired results analogues to that in Jackson Theorem 2 on real interval [1, 1] are obtained.

关键词： complex curves interpolation uniform approximation order of approximation 30E05 30E10 41A05 41A25 41A28

Experimental Research on Shear Behavior of Reinforced Concrete Composite Beams Under Uniformly Distributed Load

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china Ocean Engineering 1998年第4期13卷 467-476页

作者： ZHAO Shunbo Ass. Prof., north china institute of water conservancy and hydroelectric power, zhengzhou 450045, P. R. china. N. china Inst. water Conserv./H.P. Zhengzhou 450045 China

An experimental program was carried out to study the shear behavior of the reinforced concrete composite beam (RCCB) subjected to two-phase uniformly distributed load. A total of 12 reinforced concrete composite beams were tested: 10 of them were the RCCB subjected to two-phase uniformly distributed load, the other 2 were the comparative reinforced concrete beams cast at the same time as the RCCB subjected to one-phase uniformly distributed load. The interface of precast unit and recast concrete was natural and rough. The test range of the main composite factors: the ratio of precast section depth to composite section depth was from 0.35 to 0.65, the ratio of first-phase load moment to precast section ultimate bearing moment was from 0.25 to 0.65. Based on the test results, the stresses of the longitudinal reinforcements and stirrups, the load-bearing properties of the interface, the crack state and the failure characteristics of the RCCB under uniformly distributed load are discussed. The effects of the stirrups, the concrete strength and the composite factors on the shear resistance of the RCCB are analyzed, and the method for evaluating the shear resistance of the RCCB is proposed.

关键词： reinforced concrete composite beam shear resistance composite factor mechanism of failure

Unified solutions for stresses and displacements around circular tunnels using the Unified Strength Theory

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Science china(Technological Sciences) 2010年第6期53卷 1694-1699页

作者： ZHANG ChangGuang1,WANG JiangFeng2 & ZHAO JunHai3 1 Department of Geotechnical Engineering,Tongji University,Shanghai 200092,china 2.north china institute of water conservancy and hydroelectric power,zhengzhou 450011,china 3 School of Civil Engineering,Chang’an University,Xi’an 710061,china Department of Geotechnical Engineering Tongji University Shanghai China north china institute of water conservancy and hydroelectric power Zhengzhou China School of Civil Engineering Chang’an University Xi’an China

The unified solutions are presented for stresses and displacements around a circular tunnel subjected to a hydrostatic stress *** rock mass is assumed to be elastic-brittle-plastic and governed by the Unified Strength *** displacements are obtained accounting for three different definitions for elastic strains and different Young's modulus in the plastic *** unified solutions obtained in this paper are especially versatile in reflecting the intermediate principal stress effect to different extents for different *** conventional solutions,based on the Mohr-Coulomb failure criterion and the Generalized Twin Shear Stress yield criterion,are special cases of the present unified *** new unified solutions can compare with those computed by the latest generalized Hoek-Brown failure *** results obtained demonstrate the importance of the intermediate principal stress influence for the stresses and displacements *** effects of different definitions for elastic strains and different Young's modulus in the plastic zone on the displacements are significant.

关键词： Unified Strength Theory intermediate principal stress different definitions for elastic strains different Young’s modulus

Synergetic-bifurcated prediction model of slope occurrence and its application

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Science china(Technological Sciences) 2003年第Z1期46卷 69-77页

作者： HUANG Zhiquan & WANG Sijing north china institute of water conservancy and hydroelectric power, zhengzhou 450008, china institute of Geology & Geophysics, Chinese Academy of Sciences, Beijing 100029, china N china Inst water conservancy & Hydroelect power Zhengzhou 450008 Peoples R China Chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China

Landslide prediction is one of the most important aspects of prevention and control for geological hazards and the environmental protection. In order to study the nonlinear methods for landslide prediction, the synergetic-bifurcated model of predicting the timing of slope failure is established by combining Synergetics with Bifurcation Theory based on single-state variable friction law in this paper. The synergetic effects and bifurcated process of the factors in the slope evolution can be characterized in the model. Taking the Xintan Landslide as an example, the prediction of landslide is carried out based on the model suggested.

关键词： friction law, landslide, synergetic-bifurcated model, time prediction.

The Energy Growth Property for Harmonic Maps

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Chinese Quarterly Journal of Mathematics 1996年第1期11卷 53-55页

作者： Li Hongyi Zhao Di(north china institute of water conservancy and hydroelectric power, zhengzhou, 450045 ) 华北水利电力学院河南郑州 450045 华北水利电力学院河南郑州

In this paper,we study the energy growth property for a class of harmonic maps. A special estimation of energy growth is obtained.

关键词： harmonic maps energy density

Combustion synthesis of radioactive waste immobilization

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Rare Metals 2005年第2期24卷 119-124页

作者： ZHANGRuizhu GUOZhimeng LUXin JIAChengchang LINTao MaterialsScienceandEngineeringSchool UniversityofScienceandTechnologyBeijingBeijing100083China MaterialsScienceandEngineeringSchool UniversityofScienceandTechnologyBeijingBeijing100083China／／NorthChinaInstituteofWaterConservancyandHydroelectricPowerZhengzhou450011China

Using chromium oxide (CrO3) as an oxidant, the immobilization of simulating radioactive waste in perovskite (CaTiO3) structure by a combustion synthesis (CS) method was tested. The products were characterized by Archimedes liquid displacement technique, microhardness technique, X-ray diffraction, and scanning electron microscopy. The leaching rate was measured by the method of MCC-1 or MCC-2. The primary results show that the CS method can be used to solidify the immobilizate waste effectively.

关键词： combustion synthesis radioactive waste Immobilization perovskite

2-D NUMERICAL SIMULATION OF FLOODING EFFECTS CAUSED BY SOUTH-TO-north water TRANSFER PROJECT

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Journal of Hydrodynamics 2008年第5期20卷 662-667页

作者： SUN Dong-po XUE Hai WANG Peng-tao LU Rui-li LIAO Xiao- long north china University of water and hydroelectric power Zhengzhou 450011 China institute of Civil and water conservancy Ningxia University Yinchuan 750021 China china Pearl River water Resources Planning Designing Surveying Co. Ltd. Guangzhou 510610 China

Since the General Channel designed for the South-to-north water Transfer Project in china has to cross many rivers and streams flowing from west to east, there are potentially serious effects additional flooding on the western side of the project alignment. Therefore, a 2-D numerical model for forecasting basin flood disasters was established and verified using historical flood data. The model was applied to researching the interaction between the proposed Project and flooding events for 5 streams in the Anyang River reach as a representative case study. Simulated results indicate that the model could correctly forecast the flood, submerged area and depths, and water surface elevations along the left side of the channel. The discharge capacity and location of hydraulic structures in the transfer canal alignment were analyzed. Then adjustments to the dimensions and positioning of proposed hydraulic structures were recommended at intersections, especially the addition of a channel to transfer flood water from one stream to another, which can effectively limit the sluice and protect the Anyang City from flooding.

关键词： South-to-north water Transfer Project 2-D numerical simulation interpenetrating flood field diffiuent canal

Fuzzy Approach to Determining Priority Preorders of water Resources Projects

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Transactions of Tianjin University 2009年第2期15卷 121-125页

作者：刘英杰冯平 School of Civil Engineering Tianjin University Civil Engineering Supervisor Center North China Institute of Water Conservancy and Hydroelectric Power

In this paper,the criteria set related to the priority preorders of water resources projects is introduced.A fuzzy multiple criteria group decision-making model is established,which incorporates quantitative analysis,judgments,experience and preferences of *** model is used in practice to determine the priority preorders of five water resources projects,and the results show that the best choice can supply more new employment,domestic water and irrigation water,and has better quality.

关键词： fuzzy decision-making priority preorders water resources projects

3-D NUMERICAL STUDY OF LAMINAR AND TURBULENT FLOW INSIDE A 90-DEG-BEND SQUARE AND FLAT DUCT

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Journal of Hydrodynamics 1992年第4期4卷 97-108页

作者： Liu Qing-chao Chai Fang-Kun Chen Zhen-xi institute of water conservancy and hydroelectric power Research,Beijing 100044,P.R.china

With the application of body-fitted coordinate method and the standard k-epsilon equations,the rtumericat sotution to the averaged N-S equations is *** and turbu- tent flows inside a 90-Deg-Bent duct are studied,yield... 详细信息

关键词： 3—D laminar flow turbulent flow