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Research on secure buyer-seller watermarking protocol

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Journal of Systems Engineering and Electronics 2008年第2期19卷 370-376,384页

作者： Liu quan Chen zheng Zhou Zude School of Information Engineering Wuhan Univ. of Technology Wuhan 430070 P. R. China

A new buyer-seller watermarking protocol is proposed by applying a double encryption method and a novel mechanism of embedding a buyer＇s watermark. The protocol can effectively prevent against collusion attacks and the man in the middle attack if the third party is not trusted. Also, based on the proposed scheme for the first-hand transaction, a new buyer-reseller watermarking protocol and a formal multi-party watermarking protocol are also proposed. The proposed buyer-resell watermarking protocol only needs the original seller to provide transfer certificate and encryption-decryption service to support the second-hand transaction, and the multi-party watermarking protocol with distributed certificate authorities can overcome the difficulty in the combination of multicast mechanism with multiple unique watermarks and allow a seller to multicast the watermarked digital contents and key transaction information to n buyers. Furthermore, the idea of zero knowledge proof is also applied into the proposed scheme to allow the seller to take an effective control on the task performed by the third party.

关键词： watermarking protocol zero knowledge proof distributed certification authorities.

A survey on facial image deblurring

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Computational Visual Media 2024年第1期10卷 3-25页

作者： Bingnan Wang Fanjiang Xu quan zheng Institute of Software Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

When a facial image is blurred,it significantly affects high-level vision tasks such as face *** purpose of facial image deblurring is to recover a clear image from a blurry input image,which can improve the recognition accuracy,***,general deblurring methods do not perform well on facial ***,some face deblurring methods have been proposed to improve performance by adding semantic or structural information as specific priors according to the characteristics of the facial *** this paper,we survey and summarize recently published methods for facial image deblurring,most of which are based on deep ***,we provide a brief introduction to the modeling of image ***,we summarize face deblurring methods into two categories:model-based methods and deep learning-based ***,we summarize the datasets,loss functions,and performance evaluation metrics commonly used in the neural network training *** show the performance of classical methods on these datasets and metrics and provide a brief discussion on the differences between model-based and learning-based ***,we discuss the current challenges and possible future research directions.

关键词： facial image deblurring model-based deep learning-based semantic or structural prior

The second Eshelby problem and its solvability

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Acta Mechanica Sinica 2012年第5期28卷 1331-1333页

作者： Wen-Nan Zou quan-Shui zheng Institute for Advanced Study Nanchang University Department of Engineering Mechanics Tsinghua University

It is still a challenge to clarify the dependence of overall elastic properties of heterogeneous materials on the microstructures of non-elliposodal inhomogeneities （cracks, pores, foreign particles）. From the theory of elasticity, the formulation of the perturbance elastic fields, coming from a non-ellipsoidal inhomogeneity embedded in an infinitely extended material with remote constant loading, inevitably involve one or more integral equations. Up to now, due to the mathematical difficulty, there is almost no explicit analytical solution obtained except for the ellipsoidal inhomo- geneity. In this paper, we point out the impossibility to trans- form this inhomogeneity problem into a conventional Eshelby problem by the equivalent inclusion method even if the eigenstrain is chosen to be non-uniform. We also build up an equivalent model, called the second Eshelby problem, to investigate the perturbance stress. It is probably a better template to make use of the profound methods and results of conventional Eshelby problems of non-ellipsoidal inclusions.

关键词： The second Eshelby's problem Linear elasticity Non-ellipsoidal inhomogeneity Overall elastic proper-ties

Jet-like features of Jiulongjiang River plume discharging into the west Taiwan Strait

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Frontiers of Earth Science 2013年第3期7卷 282-294页

作者： Daifeng WANG quan'an zheng Jianyu HU State Key Laboratory of Marine Environmental Science College of Ocean and Earth Sciences Xiamen University Xiamen 361005 China Department of Atmospheric and Oceanic Science University of Maryland College Park MD 20742 USA

In-situ data from the summer cruise of 2010 in the west Taiwan Strait are used to study the spatial distribution of the Jiulongjiang River plume （JRP）. The results show that in the 2 m layer, the JRP debouches into the west Taiwan Strait in the form of jets, with one branch through the Xiamen Bay （Xiamen JR_P） and another through the channel between Jinmen and Weitou （JinWei JRP）. Driven by the summer southwesterly monsoon, the upwelling-related Dongshan low temperature and high salinity water flows northeastward in the form of a jet as well. To a certain degree, the Dongshan low temperature and high salinity jet restricts the Xiamen JRP from spreading further offshore and drags the JinWei JRP northeastward at the same time. Meanwhile, a terrestrial dissolved organic matter （DOM） distribution model on the basis of molecular collision theory in thermodynamics and statistical physics is applied to analyze the Moderate Resolution Imaging Spectroradiometer （MODIS） turbidity data. The correlation coefficient of the theoretical model to the MODIS turbidity data reaches 0.96 （significant at a 95% level of confidence）. The result clarifies the dynamic mechanism for the turbidity distribution characteristics. It is the salinity in macro-scale that plays a decisive role in the turbidity variability in the coastal water. This suggests that the satellite-derived turbidity data can be used as an indicator to show the spreading patterns of the JRP. Based on the turbidity data from 2003 to 2011, we conclude that there are four main spreading patterns of the JRP.

关键词： Jiulongjiang River plume jet current terrestrial DOM MODIS data Taiwan Strait

Modeling of the eddy viscosity by breaking waves

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Acta Oceanologica Sinica 2007年第6期26卷 116-123页

作者： ZHANG Shuwen YUAN Yeli zheng quan＇ an South China Sea Environmental Institute Guangdong Ocean University Zhanjiang 524088 China Key Laboratory of Marine Science and Numerical Modeling of State Oceanic Administration First Institute of Oceanography State Oceanic Administration Qingdao 266061 China Department of Meteorology Maryland University Maryland 20742 USA

Breaking wave induced nearsurface turbulence has important consequences for many physical and biochemical processes including water column and nutrients mixing, heat and gases exchange across air-sea interface. The energy loss from wave breaking and the bubble plume penetration depth are estimated. As a consequence, the vertical distribution of the turbulent kinetic energy （TKE）, the TKE dissipation rate and the eddy viscosity induced by wave breaking are also provided. It is indicated that model results are found to be consistent with the observational evidence that most TKE generated by wave breaking is lost within a depth of a few meters near the sea surface. High turbulence level with intensities of eddy viscosity induced by breaking is nearly four orders larger than vw1（ = κu ＊wz）, the value predicted for the wall layer scaling close to the surface, where u ＊w is the friction velocity in water, κ with 0. 4 is the yon Kármán constant, and z is the water depth, and the strength of the eddy viscosity depends both on wind speed and sea state, and decays rapidly through the depth. This leads to the conclusion that the breaking wave induced vertical mixing is mainly limited to the near surface layer, well above the classical values expected from the similarity theory. Deeper down, however, the effects of wave breaking on the vertical mixing become less important.

关键词： air-sea interface near-surface dynamics TKE dissipation rate eddy viscosity

SOLUTION OF A KIND OF LINEAR INTERNAL WAVE EQUATION

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Journal of Hydrodynamics 2005年第5期17卷 636-640页

作者： WANG Gang HOU Yi-jun zheng quan-an Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China Department of Meteorology University of Maryland Maryland 20742-2425 USA

Considering the effect of horizontal Coriolis parameter and the density compactness of seawater, which were often neglected in internal waves discussion, the governing equation of linear internal waves presented by vertical velocity only will be proposed. Under the assumption that the Brunt- Vaeisaelae frequency is exponential, an accurate analytic solution of it is obtained. Finally, the expressions of wave functions are also given.

关键词： internal wave Boussinesq approximation,Coriolis parameter Brunt-Vaeisaelae frequency

Effect of strain,strain rate and temperature on workability of AZ80 wrought magnesium alloy

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中国有色金属学会会刊：英文版 2012年第S3期22卷 650-655页

作者： Lü Wen-quan quan Guo-zheng YU Chun-tang ZHAO Lei ZHOU Jie College of Materials Science and Engineering Chongqing University

The hot deformation behavior of AZ80 wrought magnesium alloy was studied in the temperature range of 523-673 K and the strain rate range of 0.01-10 s-1 using hot compression *** the flow stresses behavior,the processing maps were calculated and analyzed according to the dynamic materials *** stable,metastable and unstable regimes were *** optimum processing conditions were suggested as following:the DRX regions in Domain #1-0.25,Domain #2-0.25,Domain #1-0.45,Domain #2-0.45,Domain #3-0.45,Domain #1-0.65 and Domain #1-0.85,and the DRV regions in Domain #3-0.25 and Domain #*** each "safe" DRX domain,it is preferable to conduct hot working in the small region around efficiency peak *** strain has a great influence on the processing *** whole area of the "safe" domains increases with the increase of true strain from 0.25 to 0.65,while it decreases with the increase of true strain from 0.65 to *** results of kinetic analysis reveal that the values of apparent activation energy in all the domains are higher than that for self-diffusion in pure magnesium (135kJ/mol),and the deformation mechanism in all the domains is likely to be cross-slip.

关键词： AZ80 magnesium alloy strain rate kinetic analysis processing map flow behavior

Correction to Hawking Radiation Characteristics of Stationary Demianski-Newman Black Hole

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Communications in Theoretical Physics 2006年第6期45卷 1026-1030页

作者： JIANG Qing-quan YANG Shu-zheng Institute of Theoretical Physics China West Normal University Nanchong 637002 China

The pure thermal spectrum in dragging coordinate system and the tunneling radiation characteristics across the event horizon for stationary Demianski-Newman black hole are researched. The result shows that the tunneling rate of the particle is relevant to Bekenstein-Hawking entropy, and the derived radiate spectrum is not strictly pure thermal, but is consistent with underlying unitary theory. Finally, we use the obtained results to reduce to stationary Kerr black hole and static Schwarzschild black hole, and lind that only when ignoring the spectrum at higher energies is the tunneling radiation spectrum consistent with Hawking pure thermal one.

关键词： Demianski-Newman black hole energy conservation angular momentum conservation tunneling rate Bekenstein-Hawking entropy

The thermodynamically directed dendrite-free lithium metal batteries on LiZn alloy surface

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Nano Research 2023年第6期16卷 8354-8359页

作者： Huanqin zheng Xu Cheng quan zheng Jianjun Zhang Tao Li Erqing Xie Ying Xu School of Physical Science and Technology Lanzhou UniversityLanzhou 730000China School of Materials and Energy Lanzhou UniversityLanzhou 730000China Southeast Research Institute of Lanzhou University Fujian 351100China

Metical lithium(Li)is one of the most promising alternatives as an anode in next-generation high energy batteries for its high theoretical specific capacity and low redox ***,severe Li dendrite growth leading to poor stability and safety issues hinders its practical ***,three-dimensional carbon cloth(CC)with full zinc oxide quantum dots(ZnO QDs)covering is rationally chosen as the substrate for the suppression of Li *** to the spontaneous reaction between ZnO QDs and molten Li,LiZn alloy is formed and covered on CC,which endows substrate with high affinity for Li adsorption and suitable barrier energy for Li *** thermodynamic regulation on substrate is beneficial for homogeneous Li nucleation and deposition,thus enabling high stability for over 1,900 h at ultrahigh current density of 10 mA∙cm^(−2) in symmetrical cell and delivering superior performance in full batteries.

关键词： LiZn alloy adsorption energy diffusion barrier dendrite-free Li metal batteries