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Higher order bulk characteristic parameters of asymmetric nuclear matter

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Science china(Physics,Mechanics & Astronomy) 2011年第S1期54卷 124-129页

作者： chen liewen1,2.1{2. of Physics, shanghai jiao tong university, shanghai 2.02.0, china 2.enter of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 730000, china 1. department of Physics Shanghai Jiao Tong University Shanghai 200240 China 2. Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator Lanzhou 730000 China

The bulk parameters characterizing the energy of symmetric nuclear matter and the symmetry energy defined at normal nuclear density ρ0 provide important information on the equation of state (EOS) of isospin asymmetric nuclear matter. While significant progress has been made in determining some lower order bulk characteristic parameters, such as the energy E0(ρ0) and incompress ibility K0 of symmetric nuclear matter as well as the symmetry energy Esym(ρ0) and its slope parameter L, yet the higher order bulk characteristic parameters are still poorly known. Here, we analyze the correlations between the lower and higher order bulk char acteristic parameters within the framework of Skyrme Hartree-Fock energy density functional and then estimate the values of some higher order bulk characteristic parameters. In particular, we obtain J0 = (-355±95) MeV and I0 = (1473±680) MeV for the third order and fourth-order derivative parameters of symmetric nuclear matter at ρ0 and Ksym = (-100 ± 165) MeV, Jsym = (2.4 ± 385) MeV, Isym = (-1309 ± 2.2.) MeV for the curvature parameter, third-order and fourth-order derivative parameters of the symmetry energy at ρ0, using the empirical constraints on E0(ρ0), K0, Esym(ρ0), L, and the isoscalar and isovector nucleon effective masses. Furthermore, our results indicate that the three parameters E0(ρ0), K0, and J0 can reasonably characterize the EOS of symmetric nuclear matter up to 2.0 while the symmetry energy up to 2.0 can be well described by Esym(ρ0), L, and Ksym.

关键词： equations of state of nuclear matter forces in hadronic systems and effective interactions symmetry energy nuclear density functional theory and extensions asymmetric matter neutron matter

PROPERTIES OF NATURAL CAVITATION FLOWS AROUND A 2.D WEDGE IN SHALLOW WATER

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Journal of Hydrodynamics 2011年第6期23卷 730-736页

作者： chen Xin LU Chuan-jing LI Jie chen Ying department of Engineering Mechanics Shanghai Jiao Tong University Shanghai 200240 China department of Engineering Mechanics and State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai 200240 China

When a body navigates with cavity in shallow water, both flexible free surface and rigid bottom wall will produce great influences on the cavity shape and hydrodynamic performances, and further affect the motion attitude and stability of the body. In the present work, characteristics of the natural cavitating flow around a 2.D symmetrical wedge in shallow water were investigated and the influences of two type boundaries on the flow pattern were analyzed. The Volume Of Fluid （VOF） multiphase flow method which is suitable for free surface problems was utilized, coupled with a natural cavitation model to deal with the mass-transfer process between liquid and vapor phases. Within the range of the cavitation number for computation （0.07-1.81）, the cavity configurations would be divided into three types, viz., stable type, transition type and wake-vortex type. In this article, the shapes of the free surface and the cavity surface, and the hydrodynamic performance of the wedge were discussed under the conditions of relatively small cavitation number （〈0.2.6）. The present numerical cavity lengths generally accord with experimental data. When the cavitation number was decreased, the cavity was found to become longer and thicker, and the scope of the deformation of the free surface also gradually extends. The free surface and the upper cavity surface correspond fairly to their shapes. However, the lower side of the cavity surface was rather leveled due to the influence of wall boundary. The lift and drag coefficients of this 2.D wedge basically keep linear relations with the natural cavitation number smaller than 0.157, whereas direct proportion for drag and inverse proportion for lift.

关键词： shallow water natural cavitation boundary effect multiphase flow

Traveling－Wave　Electrooptical　Modulator　on　Polymeric　Film　with　Reversal　Poling　Structure

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Chinese Journal of Lasers 1994年第1期B3卷 57-61页

作者： ZHOU Yi chen Yixin(department of Applied Physics, {2., shanghai2.0030, china)SUN Shiping(department of Electronical Engineering ,{2. , shanghai 2.0052. china) shanghai jiao{2. Univ Shanghai China

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关键词： reversal poling Electrooptical effect modulator

INTERFERENCE OF SIDE STRUT WITH THE NATURAL CAVITATING FLOWS AROUND A SUBMERGED VEHICLE IN WATER TUNNEL EXPERIMENTS

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Journal of Hydrodynamics 2011年第5期23卷 554-561页

作者： chen Xin YAO Yan. LU Chuan-jing chen Ying CAOJia-yi department of Engineering Mechanics Shanghai Jiao Tong University Shanghai 200240 China department of Engineering Mechanics and State Key Laboratory of Ocean Engineering Shanghai Jiao TongUniversity Shanghai 200240 China department of Engineering Mechanics Shanghai Jiao Tong University Shanghai 200240 China

To apply the measurements of model experiment in water tunnel to the actual sailing condition, it is necessary to know accurately the strut effect and its rule. In the present work, the corresponding interferences of one-side strut and two-side strut on the natural cavitating flows around a submerged vehicle in water tunnel were investigated numerically, using the homogeneous equilibrium two-phase model coupled with a natural cavitation model. The numerical simulation results show that the strut types have distinct effects on the hydrodynamic properties. For the same given upstream velocity and downstream pressure, the existence of the strut leads to an increment of natural cavitation number, reduces the low-pressure region and depresses the pressure on the vehicle surface near the sides of strut. In the case of given cavitaiton number, the influences of the two-side strut on the drag and lift coefficients are both enhanced along with the increment of attack angle, however the influence of the one-side strut gradually gets stronger on the drag coefficient but weaker on the lift coefficient contrarily. In addition, based on the present numerical results, a correction method by introducing the sigmoidal logistic function is proposed to eliminate the interference from the foil-shaped strut.

关键词： strut effect natural cavitating flow submerged vehicle water tunnel experiment

Performance Investigation of Square Concrete-filled Steel Tube Columns

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Journal of Wuhan university of Technology(Materials Science) 2011年第4期26卷 730-736页

作者：陈兵 department of Civil Engineering Shanghai Jiao Tong University

The behaviour of square concrete-filled steel tube columns under concentrical loading was studied. More than one hundred specimens were tested to investigate the effects of thickness of steel tube on the load carrying capacity of the concrete-filled tubular columns （CFTs）. The effect of the grade of concrete and content of expansive agent were also investigated. The effect of these parameters on the confinement of the concrete core was studied as well. From the experimental study it was found that for both CFTs with different strength grade concrete core, the ultimate load carrying capacity increases with the increase in percentage of expansive agent up to 2.% but it again decreases at 2.% of expansive agent content. It was also shown that the failure mode of CFTs depends on the strength grade of concrete core.

关键词： concrete filled steel tubes concrete columns ultimate capacity expansive agent

Efficient video cutout based on adaptive multilevel banded method

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Science china(Information Sciences) 2012年第5期55卷 1082-1092页

作者： chen MinGang 1,SUI BoCong 1,GAO Yan 2.& MA LiZhuang 1 1 department of Computer Science and Engineering,{2.,shanghai 2.02.0,china 2.Software Engineering Institute,East china Normal university,shanghai 2.0062.china 1. department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China2. Software Engineering Institute East China Normal University Shanghai 200062 China

Although many efficient image cutout approaches have been proposed,it is still a challenge to cut out foreground objects from a video clip because of the costs of time and memory consumption and the difficulty in maintaining temporal coherence for the cutout *** this paper,we propose a novel and efficient video cutout approach by extending a multilevel banded image segmentation method to video *** our method,the segmentation results are propagated frame by frame at the lowest resolution level based on optical flow,and are refined in image pyramids level by level through banded graph *** construct an adaptive narrow band to ensure that the segmentation result falls exactly into the narrow band during *** results show that the video cutout approach based on adaptive multilevel bands dramatically reduces time and memory costs,and achieves ideal segmentation results.

关键词： video object cutout multilevel band graph cuts video segmentation

An improved approach to the efficient construction of and search operations in motion graphs

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Science china(Information Sciences) 2012年第5期55卷 1042-1051页

作者： GAO Yan 1,chen ZhiHua 2.chen MinGang 3 & SHEN Yang 3 1 Software Engineering Institute,East {2. Normal university,shanghai 2.0062.{2. 2.department of Computer Science and Engineering,East {2. university of Science and Technology,shanghai 2.02.7,{2. 3 department of Computer Science and Engineering,{12.,shanghai 2.02.0,{2. 1. Software Engineering Institute East China Normal University Shanghai 200062 China2. Department of Computer Science and Engineering East China University of Science and Technology Shanghai 200237 China3. Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China

Motion graphs have been widely used as an effective technique in the synthesis of human *** synthesize well-formed motions,motion graphs require smooth transitions and good ***,the time and costs grow quadratically as the graph size *** this paper,we present a method to set up a hierarchical structure,called a structure *** coarse level of this graph models different motion categories and their transitions,and the fine level mainly captures different motion *** interpolation space method is used to improve the graph connectivity at the fine *** structure guides the establishment of a faster and more realistic graphical *** the building process,this structure also helps with searching the motion graph,by performing a traverse search and placing the findings into a direct look-up table or local search ***,when there is no direct link between the different motions,a navigation map is introduced to conduct an appropriate search path via a series of transition motion *** experimental results indicate that our approach could lower the computation time in construction and searching,while simultaneously providing a richer variety of motion styles.

关键词： motion graph structure table registration curve motion interpolation

Characterization of Annealed, Proton Exchange Optical Waveguides in Y-cut MgO∶LiNbO3 Crystal

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Chinese Journal of Lasers 2000年第3期9卷 47-51页

作者： CAO Xia XIA Yuxing YANG Yi WANG Pinghe chen Xianfeng (department of Applied Physics, {2., shanghai 2.0030, china) 上海交通大学上海

It is reported the results of a systematic study on planar w aveguides fabricated in Y-cut MgO∶LiNbO 3 crystal. The index profile of the as-exchanged waveguide can be modeled as a step-like one. It is deduced the diffusion coefficient and the activation energy for the proton exchange process. The surface index increases Δn e of around 0.12. after proton exchange can be reduced by post thermal annealing. The effects of the annealing on the index profile and guide depth were found not as fast as it does on a pure LiNbO 3 crystal.

关键词： proton exchange MgO∶LiNbO 3 crystal optical waveguides refractive index profile

Dual Gabriel theorem with applications

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Science china Mathematics 2006年第1期49卷 9-26页

作者： chen Xiaowu, HUANG Hualin & ZHANG Pu department of Mathematics, {2. of Science and Technology of china, Hefei 2.002., china USTC shanghai Institute for Advanced Studies, shanghai 2.1315, china Mathematical Section, the Abdus Salam ICTP, Strada Costiera 11, Trieste 34014, Italy department of Mathematics, shanghai jiao tong university, shanghai 2.0030, china 1. department of Mathematics University of Science and Technology of China Hefei 230026 China 2. USTC shanghai Institute for Advanced Studies Shanghai 201315 China 3. Mathematical Section the Abdus Salam ICTP Strada Costiera 11 Trieste 34014 Italy 4. department of Mathematics Shanghai Jiao Tong University Shanghai 200030 China

We introduce the quiver of a bicomodule over a cosemisimple coalgebra. Applying this to the coradical C0 of an arbitrary coalgebra C, we give an alternative definition of the Gabriel quiver of C, and then show that it coincides with the known Ext quiver of C and the link quiver of C. The dual Gabriel theorem for a coalgebra with a separable coradical is obtained, which generalizes the corresponding result for a pointed coalgebra. We also give a new description of C1 = C0 ∧C C0 of any coalgebra C, which can be regarded as a generalization of the first part of the well-known Taft-Wilson Theorem for pointed coal-gebras. As applications, we give a characterization of locally finite coalgebras via their Gabriel quivers, and a property of the Gabriel quiver of a quasi-coFrobenius coalgebra.

关键词： quivers, cotensor coalgebra, quasi-coFrobenius coalgebra.