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Pan-sharpening:a fast variational fusion approach

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science china(information sciences) 2012年第3期55卷 615-625页

作者： ZHOU ZeMing1, LI YuanXiang2 , SHI HanQing1, MA Ning1 & SHEN Ji2 1Institute of Meteorology, PLA university of science and technology, nanjing 211101, china 2school of Aeronautics and Astronautics, Shanghai JiaoTong university, Shanghai 200240, china 1. Institute of Meteorology PLA University of Science and Technology Nanjing 211101 China2. School of Aeronautics and Astronautics Shanghai JiaoTong University Shanghai 200240 China

A fast variational fusion model based on partial differential equations (PDEs) is presented for pansharpening. The functional framework consists of several energy terms. The gradient energy term is created by calculating the gradient vector field of the panchromatic image and the geometry of the pan is injected into the multi-spectral bands. The radiometric reduction energy term and the channel correlation energy term are defined to decrease the radiometric distortion and preserve the correlation of multi-spectral channels while enforcing the inter-bands coherence. Inspired by the shock-filtering model, an inverse diffusion term for image enhancement is put to PDEs which are deduced by minimizing the energy functional. In comparison with the state-of-the-art fusion approaches based on `a trous wavelet and non-sampled contourlet, our model can obtain the fused image with a high spatial or spectral quality by adjusting the weight coefficients of the energy terms. It can also achieve a rather good trade-off between the spatial resolution improvement and the spectral quality preserving. Our model's computational complexity for one time step is only O(N).

关键词： remote sensing image pan-sharpening energy functional fast variational fusion

Reduction of defect-induced ferromagnetic stability in passivated ZnO nanowires

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Chinese physics B 2015年第3期24卷 349-352页

作者：吴芳孟培雯罗康刘云飞阚二军 school of science Nanjing Forestry University College of information science and technology Nanjing Forestry University Key Laboratory of Soft Chemistry and Functional Materials (Ministry of Education) and Department of Applied PhysicsNanjing University of Science and Technology

First-principles calculations are performed to study the electronic structures and magnetic properties of ZnO nanowires（NM）. Our results indicate that the single Zn defect can induce large local magnetic moment（～ 2μB） in the ZnO NWs, regardless of the surface modification. Interestingly, we find that local magnetic defects have strong spin interaction, and favor room-temperature ferromagnetism in bared ZnO NW. On the other hand, although H passivation does not destroy the local magnetic moment of Zn vacancy, it does greatly reduce the spin interaction between magnetic defects. Therefore, our results indicate that H passivation should be avoided in the process of experiments to maintain the room-temperature ferromagnetism.

关键词： vacancy magnetic interaction ZnO nanowires DFT calculations

Linearly time-varying channel estimation and training power allocation for OFDM/MIMO systems using superimposed training

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science china(information sciences) 2011年第7期54卷 1456-1470页

作者： ZHANG Han 1,DAI XianHua 2 & Pan DaRu 1 1 school of physics and Telecommunication Engineering,South china Normal university,Guangzhou 510006,china 2 Department of information science and technology,SUN Yat-sen university,Guangzhou 510026,china 1. school of physics and Telecommunication Engineering South China Normal University Guangzhou 510006 China2. Department of Information Science and Technology SUN Yat-sen University Guangzhou 510026 China

We address the problem of estimating the linearly time-varying (LTV) channel of orthogonal frequency division multiplexing (OFDM)/multiple-input multiple-output (MIMO) systems using superimposed training (ST).The LTV channel is modeled by truncated discrete Fourier *** on this model,a two-step approach is adopted to estimate the LTV channel over multiple OFDM *** also present performance analysis of the channel estimation and derive a closed-form expression for the channel estimation *** is shown that the estimation variances,unlike that of the conventional ST-based schemes,approach to a fixed lower-bound as the training length increases,which is directly proportional to information-pilot power *** wireless communication systems with a limited transmission power,we optimize the ST power allocation by maximizing the lower bound of the average channel *** results show that the proposed approach outperforms the frequency-division multiplexed training schemes.

关键词： OFDM/MIMO systems linearly time-varying channel estimation superimposed training training power allocation

B→Xsγ, Xsl+l~-Decays and Constraints on Mass Insertion Parameters in MSSM

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Communications in Theoretical physics 2006年第10期46卷 687-696页

作者： XIAO Zhen-Jun,~+ LI Feng-Ying, and ZOU Wen-Jun Department of physics and Institute of Theoretical physics, nanjing Normal university, nanjing 210097, china Department of physics Nanjing Normal University Institute of Theoretical physics Nanjing Normal University

In this paper, we study the upper bounds on the mass insertion parameters (δ~q)in the minimal supersymmetric standard model. We found that the information from the measured branching ratio of B→Xl+l~-decaycan help us to improve the upper bounds on the mass insertions parameters(δ. Some regions allowed by thedata of Br(B→Xγ)are excluded by the requirement of an SM-like C(m)imposed by the data of Br(B→Xl+l~-).

关键词： B meson decay the minimal supersymmetric standard model mass insertion

Some Invariant Properties of Semi-symmetric Metric Recurrent Connections and Curvature Tensor Expressions

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Chinese Quarterly Journal of mathematics 2004年第4期19卷 355-361页

作者： ZHAO Pei-biao, SONG Hong-zao, YANG Xiao-ping(1. Department of Applied mathematics, nanjing university of science and technology, nanjing 210094, china 2. College of Mathematic and information science, Henan university , Kaifeng 475001, china) Department of Applied mathematics Nanjing University of Science and Technology Nanjing 210094China College of Mathematic and information science Henan University Kaifeng 475001 China

The projective transformation of the special semi-symmetric metric recurrent connection is studied in this paper. First of all, an invariant under this transformation is granted; Secondly, by inducing of the invariant and making use of the properties that the corresponding covariant derivative keeps being fixed under the distinctness connection, the curvature tensor expression of the Riemannian manifold is posed at the same time.

关键词： projective transformation semi-symmetric metric connection metric recurrent connection invariant curvature tensor expression covariant derivative

The Influence of Mass-Loss on the Orbit of Comet

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紫金山天文台台刊 1996年第2期15卷 56-59页

作者： Zheng Xue-tang and Yu Li-zhong(Dept.of Applied physics,nanjing university of science and technology,nanjing,china)

Using the Jeans problem and the Fermi problem of two bodies with variable masses,the influence of solar and cometary mass-loss on the orbit of comet SL9 is discussed in this *** is shown that solar and cometary mass-loss both will cause the secular and periodic terms in the semimajor axis a of comet *** influence of solar massloss on the orbit of comet SL9 is very small and it may be *** the influence of mass-loss of comet SL9 itself on its orbit is large and it may cause the secular variation in a to be about 104 km every *** cometary mass-loss will obviously influence the time and place of the comet SL9 crashing into *** it should be considered on the orbit calculation and prediction of cornet SL9.

关键词：心石

Research on magnesium alloy-based foam composites for lessening the vibration

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Research on magnesium alloy-based foam composites for lessen...

Quantum secret sharing between multiparty and multiparty with four states

第五届中国功能材料及其应用学术会议

作者： WANG Ling (Department of physics, nanjing information university of science and technology, nanjing 210044, china)

This paper deals with the morphology and performance of Mg alloy-based foam materials which can lessen vibration.

关键词： magnesium alloy foam materials lessening vibration

来源： cnki会议评论

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science china(physics,Mechanics & Astronomy) 2007年第5期50卷 572-580页

作者： YAN FengLi1, GAO Ting2 & LI YouCheng1 1 College of physics and information Engineering, Hebei Normal university, Shijiazhuang 050016, china 2 College of mathematics and information science, Hebei Normal university, Shijiazhuang 050016, china 1. College of physics and information Engineering Hebei Normal University Shijiazhuang 050016 China 2. College of mathematics and information science Hebei Normal University Shijiazhuang 050016 China

A protocol of quantum secret sharing between multiparty and multiparty with four states was presented. It was shown that this protocol can nullify the Trojan horse attack with a multi-photon signal, the fake-signal attack with Einstein-Podolsky- Rosen pairs, the attack with single photons, and the attack with invisible photons. In addition, the upper bounds of the average success probabilities were given for dishonest agent eavesdropping encryption using the fake-signal attack with any two-particle entangled states.

关键词： quantum secret sharing, security, Einstein-Podolsky-Rosen pairs

Transitivity, mixing and chaos for a class of set-valued mappings

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science china mathematics 2006年第1期49卷 1-8页

作者： LIAO Gongfu, WANG Lidong & ZHANG Yucheng Institute of mathematics, Jilin university, Changchun 130012, china Institute of Nonlinear information technology, Dalian Nations university, Dalian 116600, china Department of mathematics, university of science and technology of china, Hefei 230026, china 1. Institute of mathematics Jilin University Changchun 130012 China 2. Institute of Nonlinear information technology Dalian Nations University Dalian 116600 China 3. Department of mathematics University of Science and Technology of China Hefei 230026 China

Consider the continuous map f : x → X and the continuous map f of K,(X) into itself induced by f, where X is a metric space and K(X) the space of all non-empty compact subsets of x endowed with the Hausdorff metric. According to the questions whether the chaoticity of f implies the chaoticity of f posed by Roman-Flores and when the chaoticity of f implies the chaoticity of f posed by Fedeli, we investigate the relations between f and f in the related dynamical properties such as transitivity, weakly mixing and mixing, etc. And by using the obtained results, we give the satisfied answers to Roman-Flores's question and Fedeli's question.

关键词： set-valued mapping, transitivity, weak mixing, mixing, chaos.