检索结果-南通市图书馆

Stochastic resonance in surface catalytic oxidation of carbon monoxide induced by colored noise

在线全文

学校读者我要写书评

暂无评论

Science china Chemistry 2004年第2期47卷 106-112页

The dynamical behavior of surface catalytic oxidation reaction of Pt(110)/CO+O2.modulated by colored noise, under the condition of specific temperature, has been investigated when the partial pressure of CO gas is near the supercritical Hopf bifurcation point. By computer simulation the oscillation and stochastic resonance induced by colored noise are observed. The influences of the intensity and correlation time of colored noise on stochastic resonance are discussed. The range of sensitivity of the system to the environmental fluctuation is analyzed.

关键词： colored noise, stochastic resonance, surface catalytic reaction of Pt(110)/CO+O2. supercritical Hopf bifurcation, signal-to-noise ratio (SNR).

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

在线全文

学校读者我要写书评

暂无评论

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 {2., yantai 264025, china 2. department of physics, Shandong Normal {2., Jinan 2.0014, china School of physics and Electronic Engineering Yantai Normal University Yantai China department of physics Shandong Normal University Jinan 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.

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

在线全文

学校读者我要写书评

暂无评论

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 {2. 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.

Pointwise uniformities and pointwise metrics on fuzzy lattices

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1997年第9期42卷 718-720页

作者： SHI Fuguidepartment of Mathematics, yantai {2. College, yantai 264025, china department of Mathematics Yantai Teachers College Yantai China

UP till now there has been much spectacular and creative work about the theories of uniformi-ties and metrics in topological *** this is mostly generalizations and developmentsof Hutton’s and Erceg’s pointless *** cannot directly reflect the characteristics ofpointwise *** this note we shall set up a theory of pointwise uniformity and a theoryof pointwise metric on fuzzy lattices.

关键词： fuzzy lattice pointwise uniformity pointwise metric complete regularity remote-neighborhood mapping.

Prediction and Control of Both Wrinkle Limit and Fracture Limit on Cylindrical Cup Deep-Drawing

在线全文

学校读者我要写书评

暂无评论

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 {2., yantai2.4005,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

The Design of Lens Imaging System byMeans of Fractional Fourier Transform

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Lasers 2002年第2期11卷 27-32页

作者： CHEN Jiannong XU Qiang (department of physics, {2. teachers’ university, yantai 264025, china)D.R.Selviah(department of Electronic and Electrical Engineering, university College London, Torrington Place, London WC1E 7JE, UK) department of physics Yantai Teachers' University Yantai 264025 department of Electronic and Electrical Engineering University College London Torrington Place 英国 London WC1E 7JE

The relation between the 2.d fractional Fourier transform and the imaging process of an optical system is discussed. By changing the coordinate scales of the input plane in respect to the magnification of the optical imaging system, the fractional Fourier transform can be a powerful tool in designing specific imaging system. The Gaussian imaging formula of single lens is obtained by using the tool. Finally the procedures are generalized for designing a double-lens imaging system through an example.

关键词： lens imaging system fractional Fourier transform Gaussian imaging formula

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

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

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. {2. of Mathematics,yantai university,yantai 2.4005,china 3. LMAM,Peking university,Beijing 100871,china School of Mathematical Sciences Peking University Beijing China department of Mathematics Yantai University Yantai China LMAM Peking University 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 cohomology group of weak entwining structure

在线全文

学校读者我要写书评

暂无评论

Science china Mathematics 2007年第5期50卷 665-674页

作者： Ling JIA & Fang LI department of Mathematics, Ludong university,{2., china department of Mathematics, Zhejiang university, Hangzhou 31002., china department of Mathematics Ludong University Yantai China department of Mathematics Zhejiang University Hangzhou China

In this paper, we reveal that a weak entwining structure admits a rich cohomology theory. As an application we compute the cohomology of a weak entwining structure associated to a weak coalgebra-Galois extension.

关键词： weak entwining structure cohomology group 16W80 16W99

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

在线全文

学校读者我要写书评

暂无评论

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.