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The Simultaneous Approximation Order by Hermite Interpolation in a Smooth Domain

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Acta Mathematica Sinica,English Series 2002年第4期18卷 631-646页

作者： Tian Liang TU Department of Information Engineering, North China institute of hydroelectricity, Zhengzhou 450045, P. R. China Department of Information Engineering North China Institute of Hydroelectricity Zhengzhou P. R. China

Let D be a smooth domain in the complex plane. In D consider the simultaneous ap- proximation to a function and its ith (0≤i≤q) derivatives by Hermite interpolation. The orders of uniform approximation and approximation in the mean, are obtained under some domain boundary conditions. Some known results are included as particular cases of the theorems of this paper.

关键词： Simultaneous appoximation Hermite interpolation Approximation order Smooth domian

Developing a 2D vertical flow and sediment transport model for open channels using the Youngs-VOF method

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Chinese Journal of Oceanology and Limnology 2017年第2期35卷 444-451页

作者：赵东淼唐军吴修广林昌宁刘丽君陈剑 State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China Wenzhou Survey & Design institute of Water Conservancy & hydroelectricity Wenzhou 325009 China Zhejiang institute of Hydraulic & Estuary Hangzhou 310020 China

A 2D vertical （2DV） numerical model, without o-coordinate transformation in the vertical direction, is developed for the simulation of flow and sediment transport in open channels. In the model, time-averaged Reynolds equations are closed by the k-e nonlinear turbulence model. The modified Youngs- VOF method is introduced to capture free surface dynamics, and the free surface slope is simulated using the ELVIRA method. Based on the power-law scheme, the k-e model and the suspended-load transport model are solved numerically with an implicit scheme applied in the vertical plane and an explicit scheme applied in the horizontal plane. Bedload transport is modeled using the Euler-WENO scheme, and the grid-closing skill is adopted to deal with the moving channel bed boundary. Verification of the model using laboratory data shows that the model is able to adequately simulate flow and sediment transport in open channels, and is a good starting point for the study of sediment transport dynamics in strong nonlinear flow scenarios.

关键词： sediment transport 2D vertical model Youngs-VOF Euler-WENO bed evolution

Developing a 2D vertical flow and sediment transport model for open channels using the Youngs-VOF method

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Developing a 2D vertical flow and sediment transport model f...

Integration of Enterprise Resource Planning System Based on SOAP

浙江省水利学会2020学术年会

作者：赵东淼唐军吴修广林昌宁刘丽君陈剑 State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Wenzhou Survey & Design institute of Water Conservancy & hydroelectricity Zhejiang institute of Hydraulic & Estuary

A 2 D vertical(2 DV) numerical model,without σ-coordinate transformation in the vertical direction,is developed for the simulation of flow and sediment transport in open *** the model,time-averaged Reynolds equations are closed by the k-ε nnlinear turbulence *** modified YoungsVOF method is introduced to capture free surface dynamics,and the free surface slope is simulated using the ELVIRA *** on the power-law scheme,the k-ε model and the suspended-load transport model are solved numerically with an implicit scheme applied in the vertical plane and an elicit scheme applied in the horizontal *** transport is modeled using the Euler-WENO scheme,and the grid-closing skill is adopted to deal with moving channel bed *** of the model using laboratory data shows that the model is able to adequately simulate flow and sediment transport in open channels,and is a good starting point for study of sediment transport dynamics in strong nonlinear flow scenarios.

关键词： sediment transport 2D vertical model Youngs-VOF Euler-WENO bed evolution

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Journal of Shanghai University(English Edition) 2004年第1期8卷 43-50页

作者：卢本捷魏守平罗萍谭华 institute of hydroelectricity and Digital Engineering Huazhong University of Science and Technology Wuhan 430074 P.R. China Wuhan Xinglian Control System Company Wuhan 430070 P.R. China China Three Gorge Project Corporation Yichang 443002 P.R. China

While the enterprise resource planning (ERP) systems become more and more complex, the traditional tools such as DCOM, CORBA or EJB encounter more difficulties than before especially when heterogenous and distributed environment and multiple companies are involved. The newly born international specification SOAP brings a new solution to ERP because of its simplicity and high extensibility. This paper analyses the techniques to extend basic SOAP to implement ERP system. The techniques, including data envelope, dynamically and loosely coupled remote process calling (RPC), support to the multiple communication protocol, and security and performance improvement, greatly enhance the ability of basic SOAP and make it capable to accomplish the integration task in large scale ERP systems. All the techniques we discusse here are successfully utilized in the ERP system in the Three Gorge Cascade Dispatch Center of China Three Gorge Project Corporation.

关键词： enterprise resource planning (ERP) SOAP message queue middleware remote process calling (RPC) cascade dispatch center.

Derivatives on the isotropic tensor functions

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Science China(Physics,Mechanics & Astronomy) 2006年第3期49卷 321-334页

作者： DUI Guansuo WANG Zhengdao JIN Ming institute of Mechanics Beijing Jiaotong University Beijing 100044 China Institute of Mechanics Beijing Jiaotong University Beijing 100044 China Institute of Mechanics Beijing Jiaotong University Beijing 100044 China

The derivative of the isotropic tensor function plays an important part in continuum mechanics and computational mechanics, and also it is still an opening problem. By means of a scalar response function f ( Λ i , I 1 , I2) and solving a tensor equation, this problem is well studied. A compact explicit expression for the derivative of the isotropic tensor function is presented, which is valid for both distinct and repeated eigenvalue cases. Throughout the analysis, the formulation holds for general isotropic tensor functions without need to solve eigenvector problems or determine coefficients. On the theoretical side, a very simple solution of a tensor equation is obtained. As an application to continuum mechanics, a base-free expression for the Hill’s strain rate is given, which is more compact than the existent results. Finally, with an example we compute the derivative of an exponent tensor function. And the efficiency of the present formulations is demonstrated.

关键词： tensor functions,scalar response functions,tensor equations

Flux of organic carbon burial and carbon emission from a large reservoir: implications for the cleanliness assessment of hydropower

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Science Bulletin 2019年第9期64卷 603-611页

作者： Fushun Wang Yunchao Lang Cong-Qiang Liu Yong Qin Ningxiao Yu Baoli Wang School of Environmental and Chemical Engineering Shanghai University institute of Surface-Earth System Sciences Tianjin University

Accurately quantifying the budget of carbon sources and sinks in hydropower reservoirs is important for evaluating the cleanliness of hydroelectricity. However, current research on carbon emissions from reservoirs has rarely taken into account the organic carbon(OC) buried in sediment. Only greenhouse gas emissions from the water-air interface at reservoirs have been examined, which would result in an overestimation of the greenhouse effect of reservoirs. In November 2017, this study investigated the distribution of sediment in the Hongfeng Reservoir(HFR) in southwest China, a typical large hydropower reservoir, by using an underwater seismology monitoring system. We estimated the flux of OC into sediment using the results of a sediment survey and a dataset compiled from references. Our results show that, the HFR retained 200,715 t of OC in the sediment since its impounding after dam construction to the sampling year of 2017, when the average burial flux was 3,521 t-C aà1(106 g C aà1) and the modern burial flux was 5,449 t-C aà1. After excluding the exogenous OC, the modern valid carbon sink of the sediment was 4,632 t per year. Under the current state of the reservoir, taking the modern valid carbon sink value, the carbon emissions from the reservoir's surface, and the discharge water from the dam into consideration, the net carbon sink of the HFR is found to be 1,098.9 t-C aà1. If the hydroelectricity generated by the reservoir is converted to a carbon sink, then the total net carbon sink becomes 12,972.9 t-C aà*** work argues that both reservoir sediment and hydroelectricity are important carbon sinks and both should be included in assessments of the greenhouse effects of reservoirs.

关键词： The Hongfeng Reservoir Sediment Carbon sink Underwater seismology method

Study on integrated development and hybrid operation mode of nuclear power plant and pumped-storage power station

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Global Energy Interconnection 2019年第4期2卷 336-341页

作者： Haizheng Wang Caide Peng China Renewable Energy Engineering institute No.2Beixiaojie StreetXicheng DistrictBeijing100120P.R.China

The nuclear power plant is suitable for base-load operation, while the pumped-storage unit mainly gives play to capacity benefit in the electric power system;hence, the integrated development and hybrid operation mode of the two can better meet the needs of the electric power system. This article first presents an analysis of the necessity and superiority of such mode, then explains its meaning and analyzes the working routes. Finally, it proposes the business modes as follows: low price pumping water electricity plus nuclear power in the near term;nuclear power shifted to pumped storage power participating in market competition in the middle term;and, in the long term, nuclear power shifted to pumped storage power as primary and serving as an electric power system when needed.

关键词： Nuclear power plant Pumped-storage power station Integrated development Hybrid operation modes

Green Renewable Power and Policy in Canada: A Just Energy Transition to Net-Zero

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Journal of Geoscience and Environment Protection 2022年第3期10卷 1-12页

作者： Shirley Thompson Natural Resources institute University of Manitoba Winnipeg Canada

A just and sustainable future requires green renewable power. Net-zero by 2050 is the international goal to limit global warming to 1.5 degrees Celsius and sustain the biosphere. Green renewable energy, including wind, solar, biomass and small hydro is abundant in Canada, with potential to satisfy demand with 100% green renewables. This paper compares the renewable power landscape across Canada’s provinces considering four factors—electricity energy mix, renewable energy targets (RETs), renewable energy standard offer programs (RESOPs), feed-in tariff (FITs) or community FITs (comFITs). The provinces with green renewable energy sources typically have enabling policies of RESOP, RETs and FITS, as Prince Edward Island, Nova Scotia, Ontario and New Brunswick do. In contrast, provinces with abundant oil and gas or large-scale hydro are without pro-renewable energy policies, nor community power options, excepting green renewables in Indigenous communities due to federal funding programs. Community green renewable power projects, such as the “Indigenous off-diesel initiative”, are creating jobs, community revenue and energy sovereignty, towards just and inclusive energy in off-grid Indigenous communities. To reduce climate change, fast-tracking net-zero electricity by 2035 is recommended with the prioritization of community renewable energy by RESOPs, FITs and comFITs. For the transportation and other sectors, banning of all fossil fuels before 2040 is needed. Finally, a long-term plan to reduce the negative impacts of hydroelectricity water fluctuation is needed, considering decommissioning some dams.

关键词： Feed-in-Tariffs Renewable Energy Energy Policy Green Energy Hydro-Development Wind Energy

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21世纪前半叶长江流域水能开发

人民长江 2001年第S1期32卷 23-28页

作者： QIU Zhong-en Professor Design Institute Changjiang Water Resources Commission

The Changjiang River Valley is rich in hydraulic energy resources. A r ough estimation of the technically developable volume and the economically devel opable volume for the Changjiang River Valley was drawn out on the basis of new data. According to the estimation, the developable water energy resources of the whole valley is 257 627.60 MW with an annual energy output of 1 195.142 billion kW *h - respectively amounting to 120.6% and 116.3% of the General Investigation resu lt in 1980. The proportion of economically developable volume in the technically devel opable volume ranges the medium level in the world. According to the 3-step plan for the national economic and social development, the economic situation of our country will come up to the standard of medium-developed countries in the mid of the 21st century. Calculation reports from related departments show that the na tional electric power requirement in the Year 2050 will be 6 200 billion kW*h ( basic scheme) ～11 600 billion kW*h (ideal scheme) while the electric power req u irement of the South-west, Central and East areas of the nation within the Chang jiang River Valley will amount to 44% ～ 50 %. In order to satisfy the electric p ower requirement of the national economic and social development, the developmen t and utilization of the hydraulic energy in the Changjiang River Valley should be speeded up by stressing its strategic position and taking effective m easures. T he structure of the electric energy components of the three areas will be improv ed with the increasing proportion of the hydroelectricity. The hydroelectricity should be mainly developed in the South-west area; both the hydroelectric and fossil-f ired power should be developed in the Central China; the fossil-fired power shou ld be mainly developed in the combination of hydropower while nuclear po wer w ill be properly developed in the East China. In the Year 2050, the development o f the economically developable hydraulic energy in the

关键词：长江流域 the Changjiang River energy resources electric energy electric power power requirement Central China East China the world