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NUMeRICAL SIMULATION OF TWO-DIMeNSIONAL OVeRTOPPING AGAINST SeAWALLS ARMOReD WITH ARTIFICIAL UNITS IN ReGULAR WAVeS

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Journal of Hydrodynamics 2007年第3期19卷 322-329页

作者： LU Yong-jin LIU Hua WU Wei ZHANG Jiu-shan School of Naval Architecture Ocean and Civil Engineering Shanghai Jiaotong University Shanghai 200030 China shanghai Hydraulic engineering Design and Research Institute Shanghai 200063 China School of Naval Architecture Ocean and Civil Engineering Shanghai Jiaotong University Shanghai 200030China

A new mathematical model for the overtopping against seawalls armored with artificial units in regular waves was established. The 2-D numerical wave flume, based on the Reynolds Averaged Navier-Stokes （RANS） equations and the standard κ-ε turbulence model, was developed to simulate the turbulent flows with the free surface, in which the Volume Of Fluid （VOF） method was used to handle the large deformation of the free surface and the relaxation approach of combined wave generation and absorbing was implemented. In order to consider the effects of energy dissipation due to the armors on a slope seawall, a porous media model was proposed and implemented in the numerical wave flume. A series of physical model experiments were carried out in the same condition of the numerical simulation to determine the drag coefficient in the porous media model in terms of the overtopping discharge. Compared the computational value of overtopping over the seawall with the experimental data, the values of the effective drag coefficient was calibrated for the layers of blocks at different locations along the seawalls.

关键词： porous media overtopping seawall armored units 2-D numerical wave flume regular waves

Chimney effect Assessment of the Double-skin Facade

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湖南大学学报（自然科学版） 2009年第S1期36卷 146-150页

作者： QIU Zhong-zhu1,LI Peng2,CHOW Tin-tai3,ReN Jian-xing1,WANG Wen-huan1(1.School of energy & environment engineering,shanghai University of electric Power,shanghai 20090,china 2.School of Mechanical engineering,Tongji University,shanghai 200092,china 3.division of Building science & Technology,City University of Hong Kong,Hong Kong SAR,china) School of energy and environment engineering Shanghai University of Electric Power Shanghai 200090 China School of Mechanical engineering Tongji University Shanghai 200092 China division of Building science and Technology City University of Hong Kong Hong Kong Hong Kong

The mathematic model of heat transfer through ventilated double glazing was verified with the measured data,which were from a test chamber equipped with glass face temperature,solar radiation,ambient temperature,and wind speed measurement *** the model validation,the double-skin facade assessment was carried out through simulation with eSP-r software integrating thermal simulation and air low net work *** air flow situation in the air gap was analyzed on the basis of the hourly air velocity simulation data within typical winter week,summer week,spring week and autumn *** differences of chimney effect in different seasons were discussed,and the thermal loads resulted from the ventilated and unventilated double skin facade were presented.

关键词： chimney effect assessment double-skin facade

TURBULeNT MIXING AND eVOLUTION IN A STABLY STRATIFIeD FLOW WITH A TeMPeRATURe STeP

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Journal of Hydrodynamics 2009年第1期21卷 84-92页

作者： QIU Xiang ZHANG Dao-xiang LU Zhi-ming LIU Yu-lu shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China Department of Mathematics Shanghai University Shanghai 200444 China

Large-eddy Simulation （LeS） is applied to examine the turbulent mixing and evolution in a stably stratified flow with a thermally sharp interface. Turbulent velocity intensities and turbulent kinetic energy are analyzed by considering the mean shear and stratification effects. The evolution of turbulent mixing layer and turbulent structures are mainly investigated. The results show that the streamwise intensities are much larger than the vertical intensities, and vertical fluctuations decay more rapidly at the presence of stratification. The qualitatively computational results suggest that the mixing layer, defined by the mean temperature, inclines to the side with small inlet velocity. The evolution of the half-width of the mixing layer shows two different slopes. The turbulent structure with high vorticity is restricted in the mixing layer especially in strong stratified cases.

关键词： stratified turbulence turbulent mixing turbulent structure Large-eddy Simulation (LeS)

A THRee-DIMeNSIONAL DeSINGULARIZeD HIGH ORDeR PANeL MeTHOD BASeD ON NURBS

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Journal of Hydrodynamics 2008年第2期20卷 137-146页

作者： GAO Zhi-liang ZOU Zao-jian State Key Laboratory of Ocean engineering Shanghai Jiaotong University Shanghai 200030 China School of Naval Architecture Ocean and Civil Engineering Shanghai Jiaotong University Shanghai 200030 China

A desingularized high order panel method based on Non-Uniform Rational B-Spline （NURBS） was developed to deal with three-dimensional potential flow problems. A NURBS surface was used to precisely represent the body geometry. Velocity potential on the body surface was described by the B-spline after the source density distribution on the body surface had been solved. The collocation approach was employed to satisfy the Neurnann boundary condition and Gaussian quadrature points were chosen as both the collocation points and the source points. The singularity was removed by a combined method, so the process of the numerical computation was non-singular. In order to verify the method proposed, the unbounded flow problems of sphere and ellipsoid, the wave-making problem of a submerged ellipsoid were chosen as computational examples. It is shown that the numerical results are in good agreement with analytical solutions and other numerical results in all cases, and sufficient accuracy of numerical solution can be reached with a small number of panels.

关键词： potential flow high order panel method Non-Uniform Rational B-Spline (NURBS) desingularization

COMPUTeR SIMULATION OF GRAIN BOUNDARY STRUCTUReS IN Ni_3Al

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Acta Metallurgica Sinica(english Letters) 1990年第6期3卷 385-392页

作者： LIN Dongliang (T.L.Lin) CHeN Da shanghai Jiaotong University,shanghai,china Professor,Dept.of Materials science,shanghai Jiaotong University,shanghai 200030,china

The embedded atom type potentials and static relaxation method combined with steepest gra- dient computational technique have been used to simulate the grain boundary cohesive ener- gies,the distribution of electron density and stress field in the grain boundary,region,and oth- er related problems of[100],[110]and[111]symmetric tilt grain boundaries in Ni_3Al with different grain boundary geometrical index and *** relations with the segrega- tion or boron,behaviors or the grain boundary,and especially the stoichiometrical effect of B induced ductility have also been studied and discussed.

关键词： Ni_3Al intermetallic compound grain boundaty structure computer simulation

Pan-sharpening:a fast variational fusion approach

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science china(Information sciences) 2012年第3期55卷 615-625页

作者： ZHOU ZeMing1, LI YuanXiang2 , SHI HanQing1, MA Ning1 & SHeN Ji2 1Institute of Meteorology, PLA University of science and Technology, Nanjing 211101, china 2School of Aeronautics and Astronautics, shanghai JiaoTong University, shanghai 200240, china Institute of Meteorology PLA University of Science and Technology Nanjing China School of Aeronautics and Astronautics Shanghai JiaoTong University Shanghai China

A fast variational fusion model based on partial differential equations (PDes) is presented for pansharpening. The functional framework consists of several energy terms. The gradient energy term is created by calculating the gradient vector field of the panchromatic image and the geometry of the pan is injected into the multi-spectral bands. The radiometric reduction energy term and the channel correlation energy term are defined to decrease the radiometric distortion and preserve the correlation of multi-spectral channels while enforcing the inter-bands coherence. Inspired by the shock-filtering model, an inverse diffusion term for image enhancement is put to PDes which are deduced by minimizing the energy functional. In comparison with the state-of-the-art fusion approaches based on `a trous wavelet and non-sampled contourlet, our model can obtain the fused image with a high spatial or spectral quality by adjusting the weight coefficients of the energy terms. It can also achieve a rather good trade-off between the spatial resolution improvement and the spectral quality preserving. Our model's computational complexity for one time step is only O(N).

关键词： remote sensing image pan-sharpening energy functional fast variational fusion

Reduction of tumorigenicity of SMMC-7721 hepatoma cells by vascular endothelial growth factor antisense gene therapy

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World Journal of Gastroenterology 2001年第1期7卷 22-27页

作者： Yu Cheng Tang Yu Li Guan Xiang Qian Department of Biochemistry, shanghai Second Medical University, shanghai 200025, china Department of Biochemistry Shanghai Second Medical University Shanghai 200025China. tangyc@***

AIM: To test the hypothesis to block VeGF expression of SMMC-7721 hepatoma cells may inhibit tumor growth using the rat hepatoma model. MeTHODS: Amplify the 200 VeGF cDNA fragment and insert it into human U6 gene cassette in the reverse orientation transcribing small antisense RNA which could specifically interact with VeGF165, and VeGF121 mRNA. Construct the retroviral vector containing this antisense VeGF U6 cassette and package the replication-deficient recombinant retrovirus. SMMC-7721 cells were transduced with these virus and positive clones were selected with G418. PCR and Southern blot analysis were performed to determine if U6 cassette integrated into the genomic DNA of positive clone. Transfected tumor cells were evaluated for RNA expression by ribonuclease protection assays. The VeGF protein in the supernatant of parental tumor cells and genetically modified tumor cells was determined with eLISA. In vitro and in vivo growth properties of antisense VeGF cell clone in nude mice were analyzed. ReSULTS: Restriction enzyme digestion and PCR sequencing verified that the antisense VeGF RNA retroviral vector was successfully *** G418 selection, resistant SMMC-7721 cell clone was picked up. PCR and Southern blot analysis suggested that U6 cassette was integrated into the cell genomic DNA. Stable SMMC-7721 cell clone transduced with U6 antisense RNA cassette could express 200 bp small antisense VeGF RNA and secrete reduced levels of VeGF in culture condition. Production of VeGF by antisense transgene-expressing cells was 65+/-10 ng/L per 10(6) cells, 42045 ng/L per 10(6) cells in sense group and 485+/-30 ng/L per 10(6) cells in the negative control group, (Pe antisense-VeGF cell clone appeared phenotypically indistinguishable from SMMC-7721 cells and SMMC-7721 cells transfected sense VeGF. The growth rate of the antisense-VeGF cell clone was the same as the control cells. When S.C. was implanted into nude mice, growth of antisense-VeGF c

关键词： Gene Therapy Animals Carcinoma, Hepatocellular Cell division DNA Polymerase III endothelial Growth Factors endothelium, Vascular enzyme-Linked Immunosorbent Assay Gene expression Humans Liver Neoplasms Lymphokines Mice Mice, Nude Neovascularization, Pathologic Promoter Regions (Genetics) RNA, Antisense Research Support, Non-U.S. Gov't Transduction, Genetic Tumor Cells, Cultured Vascular endothelial Growth Factor A Vascular endothelial Growth Factors

Research of Interaction Force Coefficients Based on Model Test in Loading Condition

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Journal of shanghai Jiaotong university(science) 2010年第2期15卷 168-171页

作者：刘小健黄国樑邓德衡 Ship Hydrodynamic Laboratory division Marine Design and Research Institute of China State Key Laboratory of Ocean engineering Shanghai Jiaotong University

It is very difficult,for the component-type ship mathematical model,to estimate the interaction force coefficients among the hull,propeller and rudder. Some coefficients such as wake fraction and flow straightening coefficient were studied from the model tests in diffierent loading conditions and the normal force of rudder was tested in captive model tests to obtain the coefficients. From these results of the tests,the flow straightening coefficients increase with the increase of trims or drafts. Similarly,wake fraction coefficients are larger for the large drafts,however,become small as the trims increase. The resistance is obviously different in fully loaded condition with the trims by stern,however ,the difference is not evident when the draft decreases and the bulbous bow is above the water surface.

关键词： interaction force coefficient rudder normal force loading condition model test

JACOBI SPeCTRAL MeTHODS FOR MULTIPLe- DIMeNSIONAL SINGULAR DIFFeReNTIAL eQUATIONS

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Journal of computational Mathematics 2003年第3期21卷 325-338页

作者： Li-Han Wang Ben-yu Guo (Department of Mathematics, shanghai Normal University, shanghai 200234, china) Department of Mathematics Shanghai Normal University 上海 200234

Jacobi polynomial approximations in multiple dimensions are investigated. They are applied to numerical solutions of singular differential equations. The convergence analysis and numerical results show their advantages.

关键词： Jacobi approximations Multiple dimensions.