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Journal of zhejiang university-Science C(Computers and Electronics) 2011年第7期12卷 589-596页

作者： Guo-qiang ZENG 1,Yong-zai LU 2,Wei-Jie MAO 2 (1 college of physics & Electronic information engineering,Wenzhou university,Wenzhou 325035,China) (2 State Key Laboratory of Industrial Control Technology,Institute of Cyber-Systems and Control,zhejiang university,Hangzhou 3.0027,China) college of physics & Electronic information engineering Wenzhou University Wenzhou China State Key Laboratory of Industrial Control Technology Institute of Cyber-Systems and Control Zhejiang University Hangzhou China

Based on our recent study on probability distributions for evolution in extremal optimization (EO),we propose a modified framework called EOSAT to approximate ground states of the hard maximum satisfiability (MAXSAT) problem,a generalized version of the satisfiability (SAT) *** basic idea behind EOSAT is to generalize the evolutionary probability distribution in the Bose-Einstein-EO (BE-EO) algorithm,competing with other popular algorithms such as simulated annealing and *** results on the hard MAXSAT instances from SATLIB show that the modified algorithms are superior to the original BE-EO algorithm.

关键词： Extremal optimization (EO) Evolution Probability distributions Maximum satisfiability (MAXSAT) problem

Rose solutions with three petals for planar 4-body problems

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Science China mathematics 2010年第12期53卷 3085-3094页

作者： DENG ChunHua 1,2 , ZHANG ShiQing 1, & ZHOU Qing 3 1 Yangtze Center of mathematics and college of mathematics, Sichuan university, Chengdu 610064, China 2 Faculty of mathematics and physics, Huaiyin Institute of Technology, Huai’an 223.01, China 3 Department of mathematics, East China normal university, Shanghai 200062, China Yangtze Center of mathematics and college of mathematics Sichuan University Chengdu China Faculty of mathematics and physics Huaiyin Institute of Technology Huai’an China Department of mathematics East China Normal University Shanghai China

For planar Newtonian 4-body problems with equal masses, we use variational methods to prove the existence of a non-collision periodic choreography solution such that all bodies move on a rose-type curve with three pet... 详细信息

关键词： 4-body problems with Newtonian potentials rose solutions with three petals winding numbers variational minimization methods

A photometric study of the K-type contact binary EI CVn

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Research in Astronomy and Astrophysics 2011年第2期11卷 181-190页

作者： Yuan-Gui Yang School of physics and Electronic information,Huaibei normal university,Huaibei 23.000,China School of physics and Electronic information Huaibei Normal University Huaibei 235000 China

We present charge-coupled device （CCD） photometry for the short-period K-type binary EI CVn,observed on 2009 February 28 at the Xinglong Station of National Astronomical Observatories,Chinese Academy of *** using the Wilson-Devinney program,the photometric solution was first deduced from our V R *** results show that EI CVn is a W-type weak-contact binary with a mass ratio of qph=0.2834（±0.0010） and an overcontact degree of f=20.0%（±0.7%）.The distorted light curves were modeled by a dark spot on the cool primary component,whose area was up to 1.9% of the area of the *** on the period analysis,it is found that there exists a weak secular decrease at a rate of dP/dt= 3.11（±0.03） × 10-7 d yr-1,which may be attributed to mass transfer from the primary to the *** mass transfer occurring,the separation between both components will shrink,which may cause the degree of overcontact to ***,the weak-contact binary EI CVn may evolve into a deep-contact configuration.

关键词： stars: binaries: close -- stars: binaries: eclipsing -- stars: individual: EICVn

Modelling Accelerating Growth with Intermittent Processes in Evolving Networks

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Communications in Theoretical physics 2007年第12期48卷 1119-1122页

作者： YUAN Wu-Jie~(1,2)and LUO Xiao-Shu~1~1 college of physics and Electronic engineering,Guangxi normal university,Guilin 541004,China~2 Department of physics,Huaibei Coal Industry Teachers college,Huaibei 23.000,China college of physics and Electronic engineering Guangxi Normal University Guilin 541004 China Department of physics Huaibei Coal Industry Teachers College Huaibei 235000 China

In this paper,the acceleratingly growing network model with intermittent processes is *** thegrowing network,there exist both accelerating and intermittent *** network is grown from the number ofnodes mo and the number of links added with each new node is a nonlinearly increasing function m+aNβ（t）f（t）,whereN（t） is the number of nodes present at time t.f（t） is the periodic and bistable function with period T,whose values are1 and 0 indicating accelerating and intermittent processes,*** we denote the ratio r of acceleration timeto whole *** study the degree distribution p（k） of the model,focusing on the dependence of p（k） on the networkparameters τ,T,m,α,N,and β.It is found that there exists a phase transition point,kc such that if kc,then p（k）obeys a power-law distribution with exponent -γ1,while if k>kc,then p（k） exhibits a power-law distribution withexponent-γ2.Moreover,the exponents γ1 and γ2 are independent of τ,T,m,a,and N,while they depend only onthe parameter β.More interesting,the phase transition point is described by kc=aNβ,which is equal to the value atwhich p（k） is maximum in GM model.

关键词： acceleratingly growing network intermittent process power-law distribution

LONG TIME ASYMPTOTIC BEHAVIOR OF SOLUTION OF DIFFERENCE SCHEME FOR A SEMILINEAR PARABOLIC EQUATION (Ⅱ)

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Journal of Computational mathematics 1998年第5期16卷 571-576页

作者： Hui Feng(Shenzhen university normal college, Shenzhen 518060, China Laboratorp of Computational physics, Institute of Applied physics and Computational mathematics,P.O.Box 8009, Beijing 100088, China )Long-jnn Shen(Laboratory of Computational physics, In 深圳大学师范学院广东深圳

In this paper we prove the solution of explicit difference scheme for a semilinear parabolic equation converges to the solution of difference scheme for the relevant nonlinear stationary problem as t→∞. For nonlinear parabolic problem, we obtain the long time asymptotic behavior of its discrete solution which is analogous to that of its continuous solution. For simplicity, we discuss one-dimensional problem.

关键词： Asymptotic behavior Explicit difference scheme Semilinear parabolic equation.

Light A physics in the lepton-specific two-Higgs doublet model

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Science China(physics,Mechanics & Astronomy) 2010年第11期53卷 1981-1987页

作者： CAO JunJie 1,HENG ZhaoXia 2,3 & WAN PeiHua 1 1 college of physics & information engineering,Henan normal university,Xinxiang 453.07,China 2 Key Laboratory of Frontiers in Theoretical physics,Institute of Theoretical physics,Chinese Academy of Sciences,Beijing 100190,China 3 Kavli Institute for Theoretical physics China,Chinese Academy of Sciences,Beijing 100190,China college of physics & information engineering Henan Normal University Xinxiang China Key Laboratory of Frontiers in Theoretical physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing China Kavli Institute for Theoretical physics China Chinese Academy of Sciences Beijing China

We examine various direct and indirect constraints on the lepton-specific two-Higgs doublet model and discuss its phenomenology at colliders in the allowed parameter *** constraints we consider come from the precision electroweak data,the direct search for Higgs boson,the muon anomalous magnetic moment,as well as some theoretical consistency *** find that in the allowed parameter space the CP-odd Higgs boson A is rather light (m A < 30 GeV with 95% possibility),which is composed dominantly by the leptonic Higgs and decays dominantly into τ + τ;while the SM-like Higgs boson h (responsible largely for electroweak symmetry breaking) decays dominantly in the mode h → AA → 4τ with a large decay width,which will make the Higgs discovery more difficult at the ***,this scenario predicts rare Z decays Z → AAA and Z →τ + τA with their branching ratios ranging from 10-8 to 10-and 10-5 to 10-4 respectively,which may be accessible at the GigaZ option of the ILC.

关键词： Lepton-specific two-Higgs doublt model light Higgs boson A Z decays

Synthesis of Magnetic Manganese Ferrite

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Journal of Wuhan university of Technology(Materials Science) 2007年第3期22卷 514-517页

作者：张变芳 Department of mathematics and physics Shijiazhuang Railway University

MnFe2O4 polycrystalline powders were prepared by the chemical coprecipitation method. When the reaction temperature is above 80 ℃, through depositing and washing, the MnFe2O4 can be obtained directly without calcining. However, when it is below 80 ℃, we have to calcine the precursor in order to obtain MnFe2O4, which does not result in pure spinal structure but a mixture of MnFe2O4 and α-Fe2O3. The powders＇ magnetic property was characterized with a Vibrating Sample Magnetometer. The phase structure, crystal size and lattice constant were presented by an X-ray diffractometer. In addition, the morphology of the powder was observed with a scan electron microscope and a transmission electron microscope.

关键词： polycrystalline powders chemical coprecipitation method calcine

Extraction of vegetation fraction information from CBERS images based on VBSI vegetation index in Kaixian county

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中国有色金属学会会刊：英文版 2011年第S3期21卷 712-716页

作者： GAO Zhi-fang1, NIU Hai-peng1, LIU Jin-ping2 1. college of Surveying and Land information engineering, Henan Polytechnic university, Jiaozuo 454000, China 2. college of Geographic Sciences, Chongqing normal university, Chongqing 400047, China college of Surveying and Land information engineering Henan Polytechnic University Jiaozuo 454000 China college of Geographic Sciences Chongqing Normal University Chongqing 400047 China

Based on the mixed pixel model, the vegetation fraction of Kaixian county, China, was extracted with three free CBERS images. VBSI vegetation index suitable for CBERS images constructed with FCD (forest canopy density) model principle was put forward by ITTO (International Tropical Timber Organization) was used, considering the underestimation of vegetation fraction using NDVI in low mountain-hill region influenced by soils and shadows. And vegetation fraction was divided into five categories from low to high in order to study the special variation of vegetation cover. The results show that the vegetation cover of the region is overall good, with an average of 50%. The area of vegetation fraction below 30% accounts for 11.7% of the entire studied area, mainly concentrates in central eastern Kaixian county, where is the major development zone of cities and towns; that between 30% and 60% accounts for 62%; and that higher than 60% accounts for 26%, and mostly locates in northern middle-mountain area.

关键词： VBSI vegetation index mixed pixel model FCD model CBERS

长短波相互作用方程的Jacobi椭圆函数求解

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物理学报 2003年第11期52卷 2660-2663页

作者：郭冠平张解放浙江师范大学教育科学与技术学院金华321004 上海大学应用数学和力学研究所

推广了Jacobi椭圆函数展开方法 ,研究了复非线性演化方程组的求解问题 ,得到了长短波相互作用方程的准确包络周期解 .该结果在一定条件下包含了相应的孤波解 .

关键词：长短波相互作用方程孤波解 Jacobi椭圆函数法非线性科学行波解数学物理方法