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NUMERICAL SIMULATION OF TIP-CLEARANCE FLOW IN CASCADE

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Journal of Hydrodynamics 2003年第1期15卷 62-66页

作者： Chen Long, Yang Chen jun, Wang Guo qiangSchool of Naval Architecture and Ocean engineering, shanghai Jiaotong University, shanghai 200030, china School of Naval Architecture and Ocean engineering Shanghai Jiaotong University Shanghai 200030 China

The tip-clearance flow in a cascade was numerically simulated by solving theRANS equations of incompressible fluids. The computational model was based upon the artificialcompressibility formulation proposed by Chorin. The Baldwin-Lomax turbulence model was used to makethe governing equations closed. For the specific structure of tip-clearance flow, a multi-block gridstructure was adopted to facilitate numerical compulations. The comparison of numerical resultswith experimental data indicates that the present method is capable of simulating tip-clearanceflows with satisfactory accuracy.

关键词： cascade flow tip-clearance flow multi-block grid structure

θ-PSO: a new strategy of particle swarm optimization

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Journal of Zhejiang University-Science A(Applied Physics & engineering) 2008年第6期9卷 786-790页

作者： Wei-min ZHONG1,2, Shao-jun LI1,2, Feng QIAN1,2 (1State Key Laboratory of Chemical engineering, East china University of Science and Technology, shanghai 200237, china) (2Automation Institute, East china University of Science and Technology, shanghai 200237, china) State Key Laboratory of Chemical engineering East China University of Science and Technology Shanghai China Automation Institute East China University of Science and Technology Shanghai China

Particle swarm optimization (PSO) is an efficient, robust and simple optimization algorithm. Most studies are mainly concentrated on better understanding of the standard PSO control parameters, such as acceleration coefficients, etc. In this paper, a more simple strategy of PSO algorithm called θ-PSO is proposed. In θ-PSO, an increment of phase angle vector replaces the increment of velocity vector and the positions are decided by the mapping of phase angles. Benchmark testing of nonlinear func- tions is described and the results show that the performance of θ-PSO is much more effective than that of the standard PSO.

关键词： Particle swarm optimization (PSO) Phase angle Benchmark function

GATE TYPE SELECTION BASED ON FUZZY MAPPING

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Chinese Journal of Mechanical engineering 2002年第1期15卷 31-34,61页

作者： Wang Yu Xing Yuan Ruan Xueyu National Die & Mold CAD engineering Research Center，shanghai Jiaotong University， shanghai 200030，china National Die & Mold CAD engineering Research Center Shanghai Jiaotong University Shanghai 200030 China

Gate type selection is very important for mould design. Improper gate typemay lead to poor product quality and low production efficiency. Although numerical simulationapproach could be used to optimize gate location, the determination of gate type is still up todesigners' experience. A novel method for selecting gate type based on fuzzy logic is proposed. Theproposed methodology follows three steps: Design requirements for gate is extracted and generalized;Possible gate types (design schemes) are presented; The fuzzy mapping relationship between gatedesign requirements and gate design scheme is established based on fuzzy composition and fuzzyrelation transition matrices that are assigned by domain experts.

关键词： Gate type selection Fuzzy logic

TESTS AND APPLICATIONS OF A BOUSSINESQ MODEL WITH AMBIENT CURRENT

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Journal of Hydrodynamics 2010年第4期22卷 526-536页

作者： ZHANG Hong-sheng WANG Wei-yuan FENG Wen-jing WANG Ya-ling YANG Jian-min State Key Laboratory of Ocean engineering Shanghai Jiao Tong University Shanghai 200240 China shanghai Water Planning and Design Research Institute Shanghai 200232 China College of Transport and Communications Shanghai Maritime University Shanghai 200135 China

A new type Boussinesq model is proposed and applied for wave propagation in a wave flume of uniform depth and over a submerged bar with current present or absent,***,for the propagation of monochromatic incident wave with current absent,the Boussinesq model is tested in its complete form,and in a form without the introduction of utility velocity *** is validated that the introduction of utility velocity variables can improve the characteristics of velocity field,dispersion and *** versions of the Boussinesq models are of higher accuracy than the fully-nonlinear fourth-order model,which is one of the best forms among the existing traditional Boussinesq models that do not incorporate breaking mechanism in one ***,the Boussinesq model in its complete form is applied to simulating the propagation of bichromatic incident waves with current present or absent,respectively,and the modeled results are compared to the analytical ones or the experimental *** modeled results are reasonable in the case of inputting bichromatic incident waves with the strong opposing current present.

关键词： Boussinesq model ambient current wave-wave interactions velocity field bichromatic incident waves

Precipitates and Hydrogen Permeation Behavior in Vanadium-Bearing Microalloyed Low Carbon Steel

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Journal of Iron and Steel Research International 2011年第S1期18卷 290-295页

作者： XU Chun,LI Xiao-jie,SHEN Da-guang (Material engineering Department,shanghai Institute of Technology,shanghai 200233,china) shanghai Inst Technol Dept Mat Engn Shanghai 200233 Peoples R China

The precipitates and hydrogen permeation behavior were studied in the low carbon steel for *** the preparation of samples,Ti containing and Ti free in vanadium-bearing microalloyed low carbon steel heating at 750℃ for 3 h,were adopted after *** was found that the a large number of fine VC,TiC,TiN and Ti 4 C 2 S 2 precipitates were in samples of Vanadium-bearing microalloyed low carbon steel with Ti *** fine VC,Fe 3 C and MnS precipitates were in steels without Ti *** the numbers of precipitates in the former is more bigger than the *** activation energies for hydrogen diffusion in both samples are 26.5 and 23.7 kJ/mol,*** at 25℃,the effective diffusion coefficients in the samples for Ti containing and Ti free in Vanadium-bearing microalloyed low carbon steel were measured as 2.71×10-6 and 4.22×10-6 cm 2 /s,*** fishscaling defect occurred in the former and heavy fishscaling defect in the later.

关键词： precipitate hydrogen permeability enameling vanadium-bearing microalloyed low carbon steel

SIMULATION OF LAGRANGIAN DISPERSION USING A LAGRANGIAN STOCHASTIC MODEL AND DNS IN A TURBULENT CHANNEL FLOW

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Journal of Hydrodynamics 2009年第6期21卷 767-773页

作者： LUO Jian-ping LU Zhi-ming LIU Yu-lu School of Mechanical and Automation engineering Shanghai Institute of Technology Shanghai 200235 China shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China

The mean square displacements of fluid particles in a turbulent channel flow at Reτ = 100 are investigated using a modified Langevin equation, and are compared with DNS results. Both the Lagrangian integral time scales directly obtained from DNS and the predicted values using an empirical relation between the Eulerian and the Lagrangian integral time scales are used in the modified Langevin equation to test the effects of integral time scales on the dispersion of particles. The results show that the slight variation of the Lagrangian integral time scale has little influence on the dispersion. The agreement between results of the model equation and those of DNS is satisfactory except the streamwise dispersion for intermediate times （ 20 〈 t^＋〈 300 ）, where the results of the model equation are slightly overestimated compared to those of DNS. The cause of such discrepancy is discussed.

关键词： turbulent channel flow Lagrangian dispersion Lagrangian stochastic model

s-ordering operator expansions of quantum-mechanical fundamental representations and their applications

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Science china(Physics,Mechanics & Astronomy) 2011年第12期54卷 2150-2154页

作者： FAN HongYi 1,3 , XU YeJun 2 & YUAN HongChun 3,4 1 Department of Materials Science and engineering, University of Science and Technology of china, Hefei 230026, china 2 Department of Physics Electronic and engineering, Chizhou University, Chizhou 247000, china 3 Department of Physics, shanghai Jiao Tong University, shanghai 200030, china 4 College of Optoelectronic engineering, Changzhou Institute of Technology, Changzhou 213002, china 1. Department of Materials Science and engineering University of Science and Technology of China Hefei 230026 China3. Department of Physics Shanghai Jiao Tong University Shanghai 200030 China2. Department of Physics Electronic and Engineering Chizhou University Chizhou 247000 China4. College of Optoelectronic Engineering Changzhou Institute of Technology Changzhou 213002 China

We show that the quantum-mechanical fundamental representations, say, the coordinate representation, the coherent state representation, the Fan-Klauder entangled state representation can be recast into s-ordering operator expansion, which is elegant in form and has many applications in deriving new operator identities. This demonstrates that Dirac's symbolic method can be merged into Newton-Leibniz integration theory in a broad way.

关键词： s-ordering operator expansion operator identities quantum mechanical representation

Fusion Protein of Interleukin 4 and Diphtherial Toxin with High Cytotoxicity to Cancer Cells

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Acta Biochimica et Biophysica Sinica 2004年第6期36卷 437-442页

作者： Yu-Jian ZHANG, Xiao-BoHU, Su-Xia LI1, Li-Ping TIAN, Sheng-Li YANG, and Yi GONG* Research Center of Biotechnology, shanghai Institutes for Biological Sciences,Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, shanghai 200233, china State Key Laboratory of Bioreactor engineering, East china University of Science and Technology, shanghai 200237, china Research Center of Biotechnology Shanghai Institutes for Biological SciencesChinese Academy of Sciences Graduate School of the Chinese Academy of SciencesShanghai 200233 China State Key Laboratory of Bioreactor engineering East China University of Science and TechnologyShanghai 200237 China

Receptor of human interleukin 4 (hIL4R) has been found to be present on many types of cancer, so it may be a good target for cancer therapy. Here, fusion toxin gene DT4H has been constructed by fusing DNA sequence encoding the first 389 amino acids of diphtherial toxin (DT), which can not bind its own receptor, to human interleukin 4 (hIL4) gene. In order to improve the affinity of fusion toxin for hIL4R, a circularly permuted form of hIL4 (cpIL4) was used. The fusion gene was expressed in Escherichia coli where the fusion toxin DT4H was highly expressed. Purified DT4H was very cytotoxic to cancer cell line U251 cells, and moderate cytotoxic to HepG2 and MCF-7 cells. SGC-7901 cells were insensitive to it. The cytotoxic action of DT4H was specific because it was blocked by excess hIL4. These results suggest that DT4H may be a useful agent in the treatment of certain malignancies.

关键词： fusion toxin diphtherial toxin cancer therapy interleukin 4 IL-4 receptor

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 20% but it again decreases at 25% 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