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International Journal of Minerals,Metallurgy and Materials 1998年第4期12卷 237-240,250页

作者： Junxiang Lei(department of Mechanical Enginecring, yantai university, yantai264005,china) department of Mechanical Engineering Yantai University Yantai 264005 China

hased on both the wrinkle model and fracturc model, the wrinkle critical tangent pressure and the fractureon critical radial tensile stress are calculated respectively. The maximum tangent pressure formula in the flange deformation zone and the maximum radial tensile stress formula in the cylinder-wall pass force zone are given, and both theno-wrinkle limitl criterion and no-fracture limit criterion are put froward. The prediction and control criterion anddiagram of both the wrinkle limit and fracture limit on cylindrical cup deep-drawing, the most suitable formingzone and the limit deep-drawing coefficient are obtained. Comparing with present experience formulae and actualproduct's production, this prediction and control are quite accurate.

关键词： cylindrical cup deep-drawing wrinkle limit fracture limit deep-drawing limit

A MULTISTEP FINITE VOLUME METHOD WITH PENALTY FOR THERMAL CONVECTION PROBLEMS IN TWO OR THREE DIMENSIONS

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Journal of Systems Science & Complexity 2008年第1期21卷 129-143页

作者： Min YANG department of Mathematics Yantai University Yantai 264005 China

The author considers a thermal convection problem with infinite Prandtl number in two or three dimensions. The mathematical model of such problem is described as an initial boundary value problem made up of three partial differential equations. One equation of the convection-dominated diffusion type for the temperature, and another two of the Stokes type for the normalized velocity and pressure. The approximate solution is obtained by a penalty finite volume method for the Stokes equation and a multistep upwind finite volume method for the convection-diffusion equation. Under suitable smoothness of the exact solution, error estimates in some discrete norms are derived.

关键词： Error estimate finite volume thermal convection problem unstructured meshes.

Prediction and Control of both Wrinkle Limit and Fracture Limiton Cylindrical Cup Deep-drawing(Ⅱ)

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International Journal of Minerals,Metallurgy and Materials 1999年第3期13卷 201-204页

作者： Junxiang Lei Yonglin Kang(department of Mechanical Engineering, yantai university, yantai 264005, china)(Material Science and Engineering school, university of Science and Technology Beijing, Beijing 100083, china) department of Mechanical Engineering Yantai University Yantai 264005 China Material Science and Engineering school University of Science and Technology Beijing Beijing 100083 China

The prediction and control criterion of both the wrinkle limit and fracture limit on the cylindrical cup deep-drawing are given, and the prediction and control diagram of both the wrinkle limit and fracture limit are also given. The results show that it is suitable for no-flange cylindrical cup deep-drawing, narrow-flange cylindrical cup deep-drawing, wide-flange cylindrical cup deep-drawing/expanding compound forming and rigid punch expanding forming.

关键词： cylindrical cup wrinkle limit fracture limit deep-drawing expanding forming compound forming

The realization and structure of complete Lie algebras whose nilpotent radicals are Heisenberg algebras

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Chinese Science Bulletin 1998年第5期43卷 383-385页

作者： JIANG Cuibo 1 and MENG Daoji 2 1.department of Mathematics,yantai Teachers university, yantai 264025, china 2.department of Mathematics,Nankai university,Tianjin 300071, china. department of Mathematics Yantai Teachers University Yantai China department of Mathematics Nankai University Tianjin China

The realization and structure of complete Lie algebras whose nilpotent radicals are Heisenberg algebras over the complex field C are given.

关键词： complete Lie algebra Heisenberg algebra nilpotent radical.

NOVEL METHOD OF REALIZING THE OPTIMAL TRANSMISSION OF THE CRANK-AND-ROCKERMECHANISM DESIGN

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Chinese Journal of Mechanical Engineering 2003年第1期16卷 31-33页

作者： Fang Shijie Li Lidepartment of Mechanical Engineering,yantai university,yantai 264005, china department of Mechanical Engineering Yantai University Yantai 264005

A novel method of realizing the optimal transmission of the crank-and-rockermechanism is presented. The optimal combination design is made by finding the related optimaltransmission parameters. The diagram of the optimal transmission is drawn. In the diagram, therelation among mini-mum transmission angle, the coefficient of travel speed variation, theoscillating angle of the rocker and the length of the bars is shown, concisely, conveniently anddirectly. The method possesses the main characteristic. That it is to achieve the optimaltransmission parameters under the transmission angle by directly choosing in the diagram, accordingto the given requirements. The characteristics of the mechanical transmission can be improved togain the optimal transmission effect by the method. Especially, the method is simple and convenientin practical use.

关键词： Crank-and-rocker mechanism Optimal transmission angle Coefficient oftravel speed variation

The regular representation and regular covariant representation of crossed products of Woronowicz C^(*)-algebras

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Science china Mathematics 2005年第9期48卷 1245-1259页

作者： ZHANG Xiaoxia~(1,2) & GUO Maozheng~(1,3) 1. school of Mathematical Sciences,Peking university,Beijing 100871,china 2. department of Mathematics,yantai university,yantai 264005,china 3. LMAM,Peking university,Beijing 100871,china 1. school of Mathematical Sciences Peking University 100871 Beijing China 2. department of Mathematics Yantai University 264005 Yantai China 3. LMAM Peking University 100871 Beijing China

In this paper,it is shown that the regular representation and regular covariant representation of the crossed products A×α G correspond to the twisted multiplicative unitary operators,where A is a Woronowicz C~*-algebra acted upon by a discrete group ***,it is also shown that the regular covariant C~*-algebra is the Woronowicz C~*-algebra which corresponds to a multiplicative ***,an explicit description of the multiplicative unitary operator for C(SU_q(2) )×α (?) is given in terms of those of the Woronowicz C~*-algebra C(SU_q(2) ) and the discrete group G.

关键词： multiplicative unitary operator, Woronowicz C*-algebra, crossed product.

The influence of laser pulse on the photoabsorption spectra of Li atom in strong external field

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Science china(Physics,Mechanics & Astronomy) 2006年第2期49卷 178-186页

作者： WANG Dehua1 & LIN Shenglu2 1. school of Physics and Electronic Engineering, yantai Normal university, yantai 264025, china 2. department of Physics, Shandong Normal university, Jinan 250014, china 1. school of Physics and Electronic Engineering Yantai Normal University Yantai 264025 China 2. department of Physics Shandong Normal University Jinan 250014 China

Using the time-dependent perturbation theory and the calculation formula of the single- and double-pulse absorption spectra of the atom in strong external fields, we calculate the single- and double-pulse absorption spectra of Li atom in strong magnetic field for different pulse widths. The results show that a pulse of some width can reduce the contribution of the short period closed orbits and eliminate the contribution of the long period orbits. Compared with the single-pulse absorption spectra, we found that for some phase differences, the double-pulse laser absorption spectra are strengthened; while for others, they are reduced. Therefore, we can use the pulse laser to control the oscillation of the absorption spectra and obtain the optimization object.

关键词： laser pulse closed orbit absorption spectra.

A Fixed Point Theorem and an Equilibrium Point of an Abstract Economy in H-spaces

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Acta Mathematicae Applicatae Sinica 2003年第3期19卷 425-430页

作者： Ji-cheng Houdepartment of Mathematics, Shantou university, Shantou 515063, chinaCorrespondence address: department of Mathematics and Information Science, yantai university, yantai264005, china department of Mathematics Shantou University Shantou 515063 China department of Mathematics and Information Science Yantai University Yantai 264005 China

In this note we first prove a fixed point theorem in H-spaces which unities and extends the corresponding results in [6] and [9]. Then, by applying the fixed point theorem, we prove an existence theorem of an equilibrium point of an abstract economy in H-spaces which improves and generalizes similar result in [4].

关键词： H-space fixed points abstract economy non-compact domain Nash equilibria compactly open lower sections

Internal noise stochastic resonance in CO oxidation on nm-sized palladium particles

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Science china Chemistry 2005年第5期48卷 395-401页

作者： GONG Yubing1,2, HOU Zhonghuai1 & XIN Houwen1 1. department of Chemical Physics, university of Science and Technology of china, Hefei 230026, china 2. department of Physics, yantai Teachers university, yantai 264025, china 1. department of Chemical Physics University of Science and Technology of China 230026 Hefei China 2. department of Physics Yantai Teachers University 264025 Yantai China

Based on a stochastic mesoscopic model, the influence of internal noise on the oscillatory kinetics of the catalytic oxidation of CO on nm-sized palladium particles is studied, using the chemical Langevin equations, Poisson approximation algorithm, and exact stochastic simulation algorithm. The reaction rate oscillations are of stochastic nature due to considerable internal noise in such mesoscopic systems. It is found that the performance of the stochastic oscillations undergoes a maximum with the variation of internal noise level for a given CO partial pressure, which demonstrates the occurrence of internal noise stochastic resonance. This phe-nomenon implies that optimal internal noise would favor the reaction rate oscillation of CO oxi-dation on nm particles. Such a phenomenon is robust to the change of external parameters, such as CO pressures.

关键词： nanometer-sized palladium particles, surface catalytic CO oxidation, internal noise, stochastic resonance, chemical Langevin equation.