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Application of transmit diversity for improved robust watermarking

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Journal of Systems Engineering and Electronics 2004年第2期15卷 163-170页

作者： SunRui sunhong YaoTianren DepartmentofElectronicandInformationEngineering HuazhongUniversityofScienceandTechnologyWuhan430074P.R.China DepartmentofCommunicationEngineering WuhanUniversityWuhan430072P.R.China

Many common multimedia signal processing, including cropping, filtering, and perceptual coding, make watermark signal fading-like modification. A scheme that applies transmit diversity technique to improve robustness of digital watermarking is presented. First, the scheme decomposes the original image using wavelet pyramid algorithm and chooses the middle-frequency band for transmission channel that the watermark will be embedded into. Then the watermark is pseudo-randomly permuted. The scheme makes use of space-time coding and differential detection technique to embed and extract watermark. The extracting process has access to neither the original image nor channel state information. Experimental results demonstrate that the scheme improves the performance of robust watermarking.

关键词： digital watermark transmit diversity space-time coding differential detection wavelet transform.

Nonlinear Dynamical Symmetries of Some Two-Dimensional Quantum Systems

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Communications in Theoretical Physics 2004年第3X期42卷 379-384页

作者： RUANDong sunhong-Zhou DepartmentofPhysics TsinghuaUniversityBeijing100084China CenterofTheoreticalNuclearPhysics NationalLaboratoryofHeavyIonAcceleratorLanzhou730000China

In this paper nonlinear dynamical symmetries of three quantum systems are studied in detail, such as theKepler-Coulomb system and the isotropic harmonic oscillator in a two-dimensional curved space, and the generalizedpseudo-oscillators in the two-dimensional flat space. Their nonlinear spectrum generating algebras are shown to berelevant to polynomial angular momentum algebras.

关键词：非线性动力学对称多项式角动量代数开普勒-库仑系统谐波振荡器伪振荡器群论

Statistical multiresolution analysis in amplitude- frequency domain

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Science in China(Series F) 2004年第4期47卷 518-526页

作者： sunhong GUANBao HenriMaitre SchoolofElectronicInformation WuhanUniversityLIESMARSWuhan430072China DepartementdeTSI EcoleNationnaleSuperieuredesTelecommunication75013ParisFranceCorrespondenceshouldbeaddressedtoSunHong

A concept of statistical multiresolution analysis in amplitude-frequency domain is proposed, which is to employ the wavelet transform on the statistical character of a signal in amplitude domain. In terms of the theorem of generalized ergodicity, an algorithm to estimate the transform coefficients based on the amplitude statistical multiresolution analysis (AMA) is presented. The principle of applying the AMA to Synthetic Aperture Radar (SAR) image processing is described, and the good experimental results imply that the AMA is an efficient tool for processing of speckled signals modeled by the multiplicative noise.

关键词： statistical signal analysis multiresolution analysis SAR image processing discrete-amplitude signal processing.

Optimized algorithm for balancing clusters in wireless sensor networks

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第10期10卷 1404-1412页

作者： Mucheol KIM sunhong KIM Hyungjin BYUN School of Computer Science and Engineering Chung-Ang University 221Heuk seok-dongDongjak-guSeoul 156-756Korea

Wireless sensor networks consist of hundreds or thousands of sensor nodes that involve numerous restrictions in-cluding computation capability and battery *** control is an important issue for achieving a balanced placement of sensor *** clustering scheme is a widely known and efficient means of topology control for transmitting information to the base station in two *** automatic routing scheme of the self-organizing technique is another critical element of wireless sensor *** this paper we propose an optimal algorithm with cluster balance taken into consideration,and compare it with three well known and widely used approaches,i.e.,LEACH,MEER,and VAP-E,in performance *** results show that the proposed approach increases the overall network lifetime,indicating that the amount of energy required for com-munication to the base station will be reduced for locating an optimal cluster.

关键词： Wireless sensor networks Self-organizing sensor algorithm Clustering algorithm Optimization

Single Boson Realizations of the Higgs Algebra

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Communications in Theoretical Physics 2003年第1X期40卷 73-76页

作者： RUANDong WUChu sunhong-Zhou TheKeyLaboratoryofQuantumInformationandMeasurementsofMinistryofEducation TsinghuaUniversityBeijing100084China DepaxtmentofPhysics TsinghuaUniversityBeijing100084China InstituteofTheoreticalPhysics AcademiaSinicaBeijing100080China

We obtained for the Higgs algebra three kinds of single boson realizations such as the unitary Holstein-Primakoff-like realization, the non-unitary Dyson-like realization, and the unitary Villain-like realization. The corre-sponding similarity transformations between the Holstein-Primakoff-like realizations and the Dyson-like realizations are given.

关键词：希格斯介子代数非线性角动量代数玻色子 Higgs代数多项式角动量代数量子场论

Interleaver Design Method for Turbo Codes Based on Genetic Algorithm

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Wuhan University Journal of Natural Sciences 2004年第3期9卷 323-326页

作者： TanYing sunhong ZhouHuai-bei SchoolofElectronicInformation WuhanUniversityWuhan430072HubeiChina AdvancedResearchCenterforScienceandTechnology WuhanUniversityWuhan430072HubeiChina

This paper describes a new interleaver construction technique for turbo code. The technique searches as much as possible pseudo-random interleaving patterns under a certain condition using genetic algorithms(GAs). The new interleavers have the superiority of the S-random interleavers and this interleaver construction technique can reduce the time taken to generate pseudo-random interleaving patterns under a certain condition. The results obtained indicate that the new interleavers yield an equal to or better performance than the S-random interleavers. Compared to the S-random interleaver, this design requires a lower level of computational complexity. Key words interleaver - Turbo codes - genetic algorithm CLC number TN 911. 22 Foundation item: Supported by the National Natural Science Foundation of China (60372057) and the Key Open Laboratory on Information Science and Engineering of Railway Transportation Ministry of Beijing Jiaotong University of China (KLISAE-0103)Biography: Tan Ying (1963-), female, Associate professor, Ph. D, research direction: error control coding, analysis and design of wireless communication system.

关键词： interleaver Turbo codes genetic algorithm

Synthetic Aperture Radar Raw Signals Simulation of Extended Scenes

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Wuhan University Journal of Natural Sciences 2004年第3期9卷 327-331页

作者： SunJin-yao sunhong SchoolofElectronicInformation WuhanUniversityWuhan430072HubeiChina

A synthetic aperture radar (SAR) raw signal simulation algorithm for extended scenes is presented. This algorithm is based on the SAR two-dimensional system transform function (STF). To cope with range-variant nature of SAR STF and increase the speed of this algorithms, new formulas for range-variant phase corrections in range-Doppler (RD) domain are developed. In this way, many azimuth lines can be simulated with the same SAR STF. It only needs two-dimensional fast Fourier transform code and complex multiplications. Comparing with time-domain simulation algorithm, it is very simple and thus efficient. Simulation results have shown that this algorithm is accurate and efficient. Key words synthetic aperture radar - raw signal simulation - system transform function CLC number TP 751. 1 Foundation item: Supported by the National Natural Science Foundation of China (40376051)Biography: Sun Jin-yao (1967-), female, Ph. D. candidate, research direction: SAR image simulation and 3D recover for SAR image.

关键词： synthetic aperture radar raw signal simulation system transform function

Preparation Process and Characteristics Analysis of Ni-Al System Intermetallic Compound Coatings

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材料热处理学报 2004年第05B期25卷 970-973页

作者： sunhong-fei WANGCan-ming WANDian-mao JINTao SONGQiang MaterialResearchInstituteofShandongUniversityofScienceandTechnology TaianChina

Ni-Al system intermetallic compound coatings were acquired on the substrates of Nickel base superalloy by thermal spray accompanied with metallurgy and diffusion process. The main phases in the coatings are NiAl and Ni3Al and the microstructure oi" the coatings are dense. The coatings bond well with the substrates and show excellent characteristics of oxidation-resistance at temperature as high as 1300 °C. The coatings have been applied successfully in industry.

关键词：金属互化物高温扩散 Ni-Al合金预处理特征分析

Inhibition of nicotine-DNA adduct formation by polyphenolic compounds in vitro

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Nuclear Science and Techniques 2004年第4期15卷 219-222页

作者： CHENGYan WANGHai-Fang sunhong-Fang LIHong-Li DepartmentofChemicalBiology CollegeofChemistyandMolecularEngineeringPekingUniversityBeijing100871

Nicotine [3-(1-methyl-2-pyrrolidinyl)-pyridine], a major alkaloid in tobacco products, has proven to be a potential genotoxic compound. Some polyphenolic compounds can suppress the DNA adduction, and hence act as the potential inhibitors of carcinogenesis. In this study, the inhibitory effects of three polyphenolic compounds, curcumin (diferuloylmethane), resveratrol (trans-3, 5, 4-trihydroxystilbene) and tea polyphenols, on the nicotine-DNA adduction have been investigated in vitro using radiolabelled nicotine and liquid scintillation counting (LSC) technique. Also, the inhibition mechanism of these chemopreventive agents in regard to the activity of the biotransformation enzymes, including cytochrome P450 (CYP450), cytochrome b5 (CYb5) and glutathione S-transferase (GST), has been studied. The results demonstrated that these three polyphenols induced marked dose-dependent decrease in nicotine-DNA adducts as compared with the controls. The elimination rate of adducts reached above 46% at the highest dose for all the three agents with 51.6% for resveratrol. Correspondingly, three polyphenols all suppressed CYP450 and CYb5, whereas curcumin and resveratrol induced GST. We may arrive at a point that the three polyphenols are beneficial to prevent the nicotine adduct formation, and thus may be used to block the potential carcinogenesis induced by nicotine.

关键词：尼古丁 DNA加合物抑制作用多酚生物转化酶放射毒理学