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Modeling of suspended sediment transport with wave-induced longshore current in Huanghe (Yellow) River Delta

Acta Oceanologica Sinica 2009年第3期28卷 65-74页

作者： LI Changliang LIANG Bingchen ZHANG Jing College of Petroleum engineering China University of Petroleum（East China） Qingdao266555 China engineering College Ocean University of China Qingdao 266100 China

A three-dimensional suspended sediment model （SED） developed by the present authors is coupled with the combinatorial model of COHERENS （Luyten et al., 1999）（the three-dimensional coupled hydrodynamical-ecological model for Regional and Shelf Seas） and SWAN （Holthuijsen et al., 2004）（the third generation wave model）. SWAN is regarded as a subroutine of COHERENS and gets time- and space-varying current velocity and surface elevation from COHERENS. COHERENS gets time- and space- varying wave relevant parameters provided by SWAN. Effects of wave on current are applied in bottom shear stress, wave-induced depth-dependent radiation stress and surface drag coefficient calculation. At the same time, the damping function of suspended sediment on turbulence is introduced into COHERENS. So the sediment model SED has feedback on circulation model COHERENS. The SED obtains current associated parameters from COHERENS. Then a coupled hydrodynamic-sediment model COHERENS-SED being able to account for interaction between wave and current is obtained. COHERENS-SED is adopted to simulate three-dimensional suspended sediment transport in the Huanghe River delta. In terms of simulation results, there is obvious difference between top and bottom layer of wave-induced longshore current. The values of time series of sediment concentration gotten by COHERENS-SED have, generally, an accepted agreement extent with measurement. Significant wave heights and wave periods obtained by COHERENS-SED show that wave simulation case with currentts effect can give better agreement extent with measurement than case without current＇s effect. In the meantime, suspended sediment concentration distributing rule obtained by COHERENS-SED is similar to former researches and measurement.

关键词： Huanghe River delta suspended sediment wave-induced longshore current COHERENS SWAN COHERENS-SED

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A new transient stability margin based on dynamic security region and its applications

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Science China(Technological Sciences) 2008年第6期51卷 751-760页

作者： XUE AnCheng1, 2 & MEI ShengWei1 1 State Key Lab of Power Systems, department of Electrical engineering, Tsinghua university, Beijing 100084, China 2 Key Lab of Systems and Control, Institute of Systems Science, Chinese Academy of Sciences, Beijing 100190, China 1. State Key Lab of Power Systems Department of Electrical Engineering Tsinghua University Beijing 100084 China 2. Key Lab of Systems and Control Institute of Systems Science Chinese Academy of Sciences Beijing 100190 China

A new transient stability margin is proposed based on a new expression of dynamic security region (DSR) which is developed from the existing expression of DSR. Applications of the DSR based transient stability margin to contingency ranking and screening are discussed. Simulations in the 10-machine 39-bus New England system are performed to show the effectiveness of the proposed DSR based tran-sient stability margin.

关键词： dynamic security region (DSR) transient stability margin contingency screening

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Optimization of the inhibition of atmospheric window emission using photonic crystals

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Science China(Technological Sciences) 2010年第5期53卷 1315-1319页

作者： LI Jin & YE Hong department of Thermal Science and Energy and engineering,university of Science and Technology of China,Hefei 230026,China 1. department of Thermal Science and Energy and engineering University of Science and Technology of China Hefei 230026 China

Transfer matrix method is used to discuss the effect inhibition of photonic crystals on atmospheric window emission(ε-14 μm).According to the optical characteristics of the materials,germanium and zinc sulfide are used as the composing *** structure of the photonic crystals is optimized,and the optimal thickness values of the germanium and zinc sulfide are 0.63 and 1.11μm respectively while the ratio of optical thickness is 1:1 and the period is *** photonic crystals are prepared by evaporation coating method,and the optical properties of the photonic crystals are measured,the inhibition of the photonic crystals to atmospheric window emission is verified.

关键词： photonic crystals emission at atmospheric window inhibition

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A new method of estimating the equivalent elastic modulus of RCCD

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Science China(Technological Sciences) 2007年第z1期50卷 136-143页

作者： GU ChongShi1,2?, WU Yuan1, SU HuaiZhi1,2 & TANG LiHui1 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 College of Water Conservancy and Hydropower engineering Hohai University Nanjing 210098 China National engineering Research Center of Water Resources Efficient Utilization and engineering Safety Nanjing 210098 China

Based on the composite material mechanic theory, the analysis method for the equivalent elastic moduli which are parallel and vertical to the construction interface of RCCD is studied in this paper. The differences between the equivalent elastic moduli which are vertical to the construction interface of RCCD gotten from different methods are discussed in detail. The variation range of the equivalent elastic modulus which is vertical to the construction interface of RCCD is studied based on the principle of minimum complementary energy and the principle of minimum potential energy. The effect of the related influential factors on the equivalent elastic modulus is analyzed. The estimation formula of the equivalent modulus which is vertical to the construction interface of RCCD is proposed. The feasibility of the approach proposed in this paper is analyzed through an example.

关键词： RCCD equivalent elastic modulus variation range estimation method

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Preparation of nanocrystalline BaTiO_3 ceramics

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Science China(Technological Sciences) 2009年第6期52卷 1730-1734页

作者： DENG XiangYun1,2,LI DeJun1,LI JianBao2,WANG XiaoHui3 & LI LongTu3 1 College of Physics and Electronic Information,Tianjin Normal university,Tianjin 300387,China 2 Materials and Chemical engineering Institute,Key Laboratory for Hainan Advantage Resources and Applied Technology in Chemical engineering Material of Ministry of Education,Hainan Provincial Key Laboratory of Research on Utilization of Si-Zr-Ti,Hainan university,Haikou 570228,China 3 department of Materials Science and engineering,Tsinghua university,Beijing 100084,China College of Physics and Electronic Information Tianjin Normal University Tianjin 300387 China Materials and Chemical engineering Institute Key Laboratory for Hainan Advantage Resources and Applied Technology in Chemical Engineering Material of Ministry of Education Hainan Provincial Key Laboratory of Research on Utilization of Si-Zr-Ti Hainan University Haikou 570228 China department of Materials Science and engineering Tsinghua University Beijing 100084 China

The high-dense nanocrystalline BaTiO3(BT)ceramics with grain size smaller than 100nm have been successfully prepared by the two step sintering and the spark plasma sintering(SPS)*** successive transitions in nanograin BT ceramics from rhombohedral to orthorhombic,tetragonal and cubic transitions,similar to those in coarse BT ceramics,were revealed by in-situ temperature dependent Raman *** multiphase coexistence and the diffused phase transition character were demonstrated in the 8nm nanocrystalline BT ceramics.

关键词： nanocrystalline BaTiO3 ceramics preparation microstructure size effect

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Multi-resolution representation of digital terrain models with terrain features preservation

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Science China(Technological Sciences) 2008年第S1期51卷 145-154页

作者： LI QingQuan1,WANG Zhi1,2 & YANG BiSheng1 1 State Key Laboratory of Information engineering in Surveying,Mapping and Remote Sensing,Wuhan university,Wuhan 430079,China 2 School of Remote Sensing and Information engineering,Wuhan university,Wuhan 430079,China 1. State Key Laboratory of Information engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430079 China2. School of Remote Sensing and Information Engineering Wuhan University Wuhan 430079 China

multi-resolution TIN model is an important issue in the contexts of visu-alization,virtual reality (VR),and geographic information systems (GIS). This paper proposes a new method for constructing multi-resolution TIN models with multi-scale topographic features preservation. The proposed method is driven by a half-edge collapse operation in a greedy framework and employs a new quadric error metric to efficiently measure geometric errors. We define topographic features in a multi-scale manner using a center-surround operator on Gaussian-weighted mean curvatures. Experimental results demonstrate that the proposed method performs better than previous methods in terms of topographic features preservation,and is able to achieve multi-resolution TIN models with a higher accuracy.

关键词： digital terrain models level of detail differential-geometry quadric error metrics topographic feature

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Inconsistency between WMAP data and released map

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Chinese Science Bulletin 2010年第10期55卷 907-909页

作者： LIU Hao1 & LI TiPei1,2,3 1 Key Laboratory of Particle Astrophysics,Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China 2 department of Physics & Center for Astrophysics,Tsinghua university,Beijing 100084,China 3 department of engineering Physics & Center for Astrophysics,Tsinghua university,Beijing 100084,China Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China department of Physics & Center for Astrophysics Tsinghua University Beijing China department of engineering Physics & Center for Astrophysics Tsinghua University Beijing China

A remarkable inconsistency between the calibrated differential time-ordered data (TOD) of the Wilkinson Microwave Anisotropy Probe (WMAP) mission,which is the input for map-making,and the cosmic microwave background (CMB) temperature maps published by the WMAP team is revealed,indicating that there must exist a serious problem in the map making routine of the WMAP *** inconsistency is easy to be confirmed without the use of WMAP map-making *** view of the importance of this issue for cosmology study,we invite readers to check it by themselves.

关键词：威尔金森微波各向异性探测器 WMAP 地图制作宇宙微波背景有序数据制作软件 TOD CMB

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Hematopoietic Stem Cells Expansionin Rotating Wall Vessel

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生物医学工程学杂志 2005年第S1期22卷 99-100页

作者： Yang LIU~1 Tian-Qing LIU~(1Δ) Xiu-Bo FAN~1 Dan GE~1 Zhan-Feng CUI~2 Xue-Hu MA~11(Stem Cell and Tissue engineering Laboratory, Dalian university of Technology, Dalian 116024, China)2(department of engineering Science, Oxford university, Oxford OX1 3PJ, uk) Stem Cell and Tissue engineering Laboratory Dalian University of Technology Dalian 116024 China department of engineering Science Oxford University Oxford OX1 3 PJ UK

1 IntroductionClinical trials have demonstrated that ex vivo expanded hematopoietic stem cells (HSCs) and progenitors offer great promise in reconstituting in vivo hematopoiesis in patients who have undergone intensive *** is therefore necessary to develop a clinical-scale culture system to provide the expanded HSCs and *** culture systems such as T-flasks and gas-permeable blood bags are the most widely used culture devices for expanding hematopoietic cells. But they reveal several inherent limitations: ineffective mixing, lack of control options for dissolved oxygen and pH and difficulty in continuous feeding, which restricts the usefulness of static systems. Several advanced bioreactors have been used in the field of HSCs expansion. But hematopoietic cells are extremely sensitive to shear, so cells in bioreactors such as stirred and perfusion culture systems may suffer physical damage. This problem will be improved by applying the rotating wall vessel (RWV) bioreactor in clinic because of its low shear and unique structure. In this research, cord blood (cb) HSCs were expanded by means of a cell-dilution feeding protocol in RWV.

关键词： Hematopoietic Stem Cells Expansionin Rotating Wall Vessel

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Reliability-aware automatic composition approach for web services

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Science China(Information Sciences) 2012年第4期55卷 921-937页

作者： LI Mu 1,2,LI Bo 1,2 & HUAI JinPeng 1,2.1 State Key Laboratory of Software Development Environment,Beihang university,Beijing 100191,China 2 School of Computer Science and engineering,Beihang university,Beijing 100191,China 1. State Key Laboratory of Software Development Environment Beihang University Beijing 100191 China2. School of Computer Science and Engineering Beihang University Beijing 100191 China

In this paper,we study the reliability-aware synthesis problem for composing available services automatically and guaranteeing that the composed result satisfies the specification,such as temporal constraints of functionality and reliability,centered on a synthesis model for mediator of web services composition (CSM).This approach focuses on handling attributes and state relations,and permitting users and services to operate over them,i.e.,read /write their data values and compare them according to a dense state *** show that the reliability-aware synthesis problem for the specification is EXPTIME-complete and we give an exponential-time algorithm (CSM-NSA) which for a given formula ψ and a synthesis model,synthesizes available services in the library satisfying ψ over the synthesis model (if they exist) or responds with "not satisfiable" (otherwise).The specification ψ is a fragment of PCTL (probabilistic computation tree logic),obtained from "ordinary" CTL (computation tree logic) by replacing the EX,AX,EU and AU operation with their quantitative counterparts X >p,X =1,U >p,and U =1,*** opposed to NSA,we provide a more effective algorithm to replace the NSA algorithm called CSM-HSA (heuristic synthesis algorithm).Though HSA is an incomplete algorithm,the answer is *** experiments show that the HSA algorithm solves the problem of reliability-aware service synthesis effectively and efficiently.

关键词： reliability web services synthesis problem synthesis model heuristic algorithm

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Study on H atoms diffusion and adsorption properties of MgH_2-V systems

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Science China(Technological Sciences) 2008年第7期51卷 979-988页

作者： ZHOU DianWu1,2, LIU JinShui3 & PENG Ping3 1 State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body, Hunan university, Changsha 410082, China 2 College of Mechanical and Automatic engineering, Hunan university, Changsha 410082, China 3 College of Materials Science and engineering, Hunan university, Changsha 410082, China 1. State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan University Changsha 410082 China 2. College of Mechanical and Automatic engineering Hunan University Changsha 410082 China 3. College of Materials Science and engineering Hunan University Changsha 410082 China

Based on experimental results that VH0.81/MgH2 interface was found during the process of mechanically milling MgH2+5at.%V nanocomposite, H atoms diffusion and adsorption properties of MgH2-V systems have been investigated by using a first-principles plane-wave pseudopotential method based on the density functional theory. The results are as follows. When VH/MgH2 interface is formed due to V alloying MgH2 phase, the vacancy formed by H atoms near VH phase region is more stable than that without V alloying, while vacancy near MgH2 phase region is less stable than that without V alloying. During the process of H atoms diffusion after V alloying, the max migration barrier energy of H atoms in MgH2-V systems is reduced compared with that of MgH2 phase, which means that H atoms diffuse easily. When H diffuses into VH from MgH2 across VH/MgH2 interface, among three substitutions such as the replacement of H for V vacancy, or interstitial site or V atoms, the replacement of H for V vacancy has the strongest diffusion ability, next interstitial site, and finally V atoms site. As far as H adsorbed on different surfaces of VH phase is concerned, physical adsorption is carried out more easily than chemical adsorption, and the behavior of H atoms adsorbed on the surface near VH phase region can be found more easily than that near MgH2 phase region.

关键词： plane-wave pseudopotential theory magnesium hydride diffusion adsorption

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