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NUMERICAL SIMULATION OF TRANSIENT FLOW AROUND A SHIP IN UNSTEADY BERTHING MOTION

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Journal of Hydrodynamics 2009年第3期21卷 379-385页

作者： WANG Hua-ming ZOU Zao-jian TIAN Xi-min school of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai 200240 China school of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai 200240 State Key Laboratory of Ocean engineering Shanghai Jiao Tong University Shanghai 200030 China Marine Design and Research Institute of china Shanghai 200011 China

Ship berthing is a specific maneuver operation. The flow around a berthing ship and the forces acting on the hull are quite different from those for a ship in normal navigation. By solving the unsteady Reynolds-Averaged Navier-Stokes （RANS） equations, the transient flow field around a ship undergoing unsteady lateral motion is simulated and the varying lateral hydrodynamic force acting on the hull is evaluated in this article. The numerical results obtained with different turbulence models are analyzed and compared with experimental results and other numerical results published in literature, and a turbulence model more suitable for simulation of the viscous flow around a ship undergoing unsteady berthing is determined.

关键词： ship berthing transient flow lateral hydrodynamic force numerical simulation

IDENTIFICATION OF ABKOWITZ MODEL FOR SHIP MANOEUVRING MOTION USING ε-SUPPORT VECTOR REGRESSION

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Journal of Hydrodynamics 2011年第3期23卷 353-360页

作者： ZHANG Xin-guang ZOU Zao-jian school of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai 200240 China school of Naval Architecture Ocean and Civil Engineering and State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai 200240 China

By analyzing the data of longitudinal speed, transverse speed and rudder angle etc. in the simulated 10°/10°zigzag test, the hydrodynamic derivatives in the Abkowitz model for ship manoeuvring motion are identified by using e-Support Vector Regression （ε -SVR）. To damp the extent of parameter drift, a series of random numbers are added into the training samples to reconstruct the training samples. The identification results of the hydrodynamic derivatives are compared with the Planar Motion Mechanism （PMM） test results to verify the identification method. By using the identified Abkowitz model, 2.°/2.° zigzag test is numerically simulated. The simulated results are compared with those obtained by using the Abkowitz model where the hydrodynamic derivatives are obtained from PMM tests. The agreement is satisfactory, which shows that the regressive Abkowitz model has a good generalization performance.

关键词： ship manoeuvring Abkowitz model parameter identification e -Support Vector Regression ( ~ -SVR)

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 {2. and engineering, University of {2. and Technology of{3., Hefei 2.0}02.,{3. 2.Department of Physics Electronic and engineering, Chizhou University, Chizhou 2.7000,{3. 3.Department of Physics, shanghai {12. tong University, shanghai 2.0030,{3. 4 College of Optoelectronic engineering, Changzhou Institute of Technology, Changzhou 2.3.02.{3. Department of Materials science and engineering University of Science and Technology of China Hefei China Department of Physics Shanghai Jiao Tong University Shanghai China Department of Physics Electronic and engineering Chizhou University Chizhou China College of Optoelectronic engineering Changzhou Institute of Technology Changzhou 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

NUMERICAL INVESTIGATION ON THE AEROELASTIC BEHAVIOR OF AN AIRSHIP WITH HULL-FIN CONFIGURATION

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Journal of Hydrodynamics 2010年第2期22卷 207-213页

作者： LIU Jian-min LU Chuan-jing - XUE Lei-ping Marine engineering Institute Jimei University Xiamen 361021 China school of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai 200240China State Key Laboratory of Ocean engineering Shanghai Jiao Tong University Shanghai 200030 China

Numerical investigation was conducted on an airship of hull-fin configuration for aerodynamic and aeroelastic characteristics in three-dimensional viscous *** mathematical model was built and the corresponding numerical code was developed for the fluid-structure interaction *** governing equations of the viscous flow with LL-Low Reynolds modified model were solved by the standard SIMPLE algorithm based on the finite volume method.A fluid-structure coupled method was employed to solve the nonlinear aeroelasticity problem for the *** computational results of the viscous flow are in good agreement with the experimental *** simulation on the aeroelastic behavior of the airship in a trimmed flight reveals the effect of structure flexibility on the aerodynamic performance.

关键词： fluid-structure interaction airship aeroelasticity flexibility

Superelasticity of TiPdNi Alloys with and without Rare Earth Ce Addition

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Journal of Materials science & Technology 2003年第2期19卷 179-182页

作者： Qingchao TIAN, Jiansheng WU and Yifeng CHENGKey Laboratory of the Ministry of Education for High Temperature Materials and Tests, school of Materials science and {2., {3. jiao tong Univ., shanghai 2.0030, china Sch. of Mat. Sci. and Eng. Shanghai Jiaotong Univ. Shanghai 200030 China

Ti50.6Pd3.Ni19.4 and Ti51Pd2.Ni2. (Ce) alloys have been prepared under various temperatures for long time annealing. Differential scanning calorimetery (DSC), X-ray diffraction (XRD) and tensile test were employed to investigate the phase transformation behavior and superelasticity of the alloys. It has been found that the phase transformation temperature of Ti50.6Pd3.Ni19.4 is about 40C higher than that of Ti51Pd2.Ni2.(Ce), and do not change much with different annealed temperature. Obvious superelasticity is retained in Ti50.6Pd3.Ni19.4 alloy annealed at 400C for 18 h, and annealing at higher temperature shows a deterioration of this property. The Ce addition in TisiPd2.Ni2. alloy significantly delays recrystallization, increases yied strength and elastic modulus, but the superelasticity is poor.

关键词： TiNi-Pd Shape memory alloy Superelasticity

NEAR WAKE OF A MODEL HORIZONTAL-AXIS WIND TURBINE

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Journal of Hydrodynamics 2009年第2期21卷 285-291页

作者： HU Dan-mei DU Zhao-hui school of Power and Enviromental engineering Shanghai University of Electric Power Shanghai 200090 China school of Mechanical engineering Shanghai Jiao Tong University Shanghai 200240 China

An experimental investigation on the properties of the near wake behind the rotor of a Horizontal-Axis Wind Turbine （HAWT） was carried out at model scale. Measurements were made with a stationary slanted hot-wire anemometer using the technique of phase-locked averaging. The primary aim is to study the formation and development of the three-dimensional wake. Five axial locations were chosen within four chord lengths of the blades over a range of tip speed ratios. The results show that during the downstream developmerit of the wake, the wake centre traces a helical curve with its rotation direction opposite to that of the rotor. The distribution of mean velocity behind the HAWT rotor reveals an expansion and a decay of the three-dimensional wake. The shapes of the mean velocity distribution are similar along the blades span at the same downstream axial location. It is shown that the turbulence levels in the wake are higher than those in the non-wake region. The circumferential component and the radial component of the turbulence intensity are higher than the axial component. Our study offers some food of thought for better understanding of the physical features of the flow field as well as the performance of HAWT.

关键词： horizontal-axis wind turbine wake flow hot-wire anemometry experimental

On the sensor order in sequential integrated probability data association filter

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science china(Information sciences) 2012年第3期55卷 491-500页

作者： WANG Yang1 , JING ZhongLiang1, HU ShiQiang1, ZHANG HongJian2.& WU JingJing1 1school of Aeronautics and Astronautics, shanghai {2. {3. University, shanghai 2.02.0, china 2.0} of Electronic, Information and Electrical engineering, shanghai {2. {3. University, shanghai 2.02.0, china school of Aeronautics and Astronautics Shanghai Jiao Tong University Shanghai China school of Electronic Information and Electrical Engineering Shanghai Jiao Tong University Shanghai China

The processing order of sensors with different detection probabilities and in different clutter densities in a multi-sensor system is investigated in this paper. A sequential implementation of the integrated probability data association (IPDA) algorithm under random set framework is derived. Under the assumptions of different detection probabilities and different clutter densities of individual sensor in a multi-sensor system, we reach the conclusion that the sequential IPDA filter depends on the order analyzing the target existence probability of varying sensor orders. Moreover, we obtain the optimal order of sensors for the sequential IPDA filter in terms of maximizing the target existence probability. The conclusions are demonstrated by simulation results.

关键词： sequential integrated probability data association random finite set optimal sensor order

Modeling of human colonic blood flow for a novel artificial anal sphincter system

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Journal of Zhejiang University-science B(Biomedicine & Biotechnology) 2008年第9期9卷 734-738页

作者： Peng ZAN, Guo-zheng YAN, Hua LIU (school of Electronics, Information and Electrical engineering, {2. {3. tong University, {2. 2.02.0, china) school of Electronics Information and Electrical Engineering Shanghai Jiao Tong University Shanghai 200240 China. zanpeng@***

A novel artificial anal sphincter system has been developed to simulate the normal physiology of the human anorectum. With the goal of engineering a safe and reliable device, the model of human colonic blood flow has been built and the relationship between the colonic blood flow rate and the operating occlusion pressure of the anorectum is achieved. The tissue ischemia is analyzed based on constitutive relations for human anorectum. The results suggest that at the planned operating occlusion pressure of less than 4 kPa the artificial anal sphincter should not risk the vascularity of the human colon.

关键词： Incontinence Artificial anal sphincter Colonic blood flow Tissue ischemia

SIMULATION OF BLOOD FLOW IN INTRACRANIAL ICA-PCOMA ANEURYSM VIA COMPUTATIONAL FLUID DYMAMICS MODELING

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Journal of Hydrodynamics 2009年第5期21卷 583-590页

作者： WANG Qing WANG Wei-zhe FEI Zhi-min LIU Ying-zheng CAO Zhao-min school of Mechanical engineering Shanghai Jiao Tong University Shanghai 200240 China Renji Hospital Shanghai Jiao Tong University Shanghai 200001 China

In the present study, hemodynamics of the internal carotid artery-posterior communicating artery （ICA-PComA） was numerically modeled with CFD approach. The steady and pulsating blood flow in the ICA-PComA was simulated. The main concern was placed on the influence of aneurysm geometry on the local hemodynamics by changing the sac diameter and Aspect Ratio （AR） of the aneurysm. The numerical results show the significantly weakened Wall Shear Stress （WSS） and the intensified wall pressure in the aneurysm as AR is increased. Two factors, i.e., low WSS and high pressure of the aneurysm, may play important roles in the fragile change of the aneurysm and the final rupture. The distributions of Time-Averaged WSS （TAWSS）, Oscillatory Shear Index （OSI） and spatial WSS Gradients （WSSG）） were determined and discussed in view of their influences on the evolution of ICA-PComA aneurysm.

关键词： CFD intracranial aneurysm hemodynamics