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SEMI-FRAGILE WATERMARKING ALGORITHM FOR IMAGE TAMPERS LOCALIZATION AND RECOVERY

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Journal of Electronics(China) 2008年第3期25卷 343-351页

作者： jiang Xuemei Liu quan School of Information Engineering Wuhan University of Technology Wuhan 430070 China

Two watermarks are embedded into the original image. One is the authentication watermark generated by secret key, which is embedded into the sub-LSB （Least Significant Bit） of the original image for tamper localization; the other is the recovery watermark for tamper recovering. The original image is divided into 8 x 8 blocks and each block is transformed by Discrete Cosine Transform （DCT）. For each block, some lower frequency DCT coefficients are chosen to be quantized and binary encoded so as to gain the recovery watermark of each block, and the recovery watermark is embedded into the LSB of another block by chaos encryption and authentication chain technology. After the two watermarks being detected, the location of any minute changes in image can be detected, and the tampered image data can be recovered effectively. In the paper, the number of coefficients and their bit lengths are carefully chosen in order to satisfy with the payload of each block and gain the capability of self-recovering. The proposed algorithm can well resist against possible forged attacks. Experimental results show that the watermark generated by the proposed algorithm is sensitive to tiny changes in images, and it has higher accuracy of tamper localization and good capability of the tamper recovery.

关键词： Image authentication Tamper localization Image recovery Semi-fragile watermark

Erasable Ferroelectric Domain Wall Diodes

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Chinese Physics Letters 2021年第1期38卷 121-124页

作者： Wei Zhang Chao Wang Jian-Wei Lian Jun jiang An-quan jiang State Key Laboratory of ASIC&System School of MicroelectronicsFudan UniversityShanghai 200433China

The unipolar diode-like domain wall currents in LiNbO3 single-crystal nanodevices are not only attractive in terms of their applications in nonvolatile ferroelectric domain wall memory,but also useful in half-wave and full-wave rectifier systems,as well as detector,power protection,and steady voltage *** traditional diodes,where the rectification functionality arises from the contact between n-type and p-type conductors,which are unchanged after off-line production,ferroelectric domain wall diodes can be reversibly created,erased,positioned,and shaped,using electric *** demonstrate such functionality using ferroelectric mesa-like cells,formed at the surface of an insulating X-cut LiNbO_(3) single *** the application of an in-plane electric field above a coercive field along the polar Z axis,the domain within the cell is reversed to be antiparallel to the unswitched bottom domain via the formation of a conducting domain *** wall current was rectified using two interfacial volatile domains in contact with two side Pt *** the nonvolatile inner domain wall,the interfacial domain walls disappear to turn off the wall current path after the removal of the applied electric field,or under a negative applied voltage,due to the built-in interfacial imprint *** novel devices have the potential to facilitate the random definition of diode-like elements in modern large-scale integrated circuits.

关键词： switched ferroelectric interfacial

P-V criticality and Joule-Thomson expansion of charged AdS black holes in the Rastall gravity

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Chinese Physics C 2020年第6期44卷 176-181页

作者： Yuan Meng Jin Pu Qing-quan jiang College of Physics and Space Science China West Normal UniversityNanchong 637002China School of Physics University of Electronic Science and Technology of ChinaChengdu 610054China

We discuss the P-V criticality and the Joule-Thomson expansion of charged AdS black holes in the Rastall gravity. We find that although the equation-of-state of a charged AdS black hole in the Rastall gravity is related to the Rastall parameter λ, its reduced equation-of-state at the critical point is independent of the Rastall parameter λ, as is the case in the Einstein gravity where λ=0. This is the reason why the critical exponents are not related to the Rastall parameter λ. We also find that the inversion temperature Ti is related to the Rastall parameter λ,but that the minimum inversion temperature Timin and the ratio ε between the minimum inversion temperature and the critical temperature are both independent of the Rastall parameter λ. At the critical point, the thermodynamic evolution of a charged AdS black hole in the Rastall gravity behaves as in the van der Waals fluid and charged AdS black hole in the Einstein gravity. We show the inversion curves and isenthalpic curves in the T-P plane and analyze the effect of the Rastall constant λ on the inversion curves of a charged AdS black hole during the Joule-Thomson expansion.

关键词： P-V criticality Joule-Thomson expansion AdS black hole Rastall gravity

Investigation of stress-induced progressive failure of mine pillars using a Voronoi grain-based breakable block model

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International Journal of Mining Science and Technology 2024年第5期34卷 713-729页

作者： Shili Qiu Shirui Zhang quan jiang Shaojun Li Hao Zhang Qiankuan Wang State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China

The Voronoi grain-based breakable block model(VGBBM)based on the combined finite-discrete element method(FDEM)was proposed to explicitly characterize the failure mechanism and predict the deformation behavior of hard-rock mine *** influence of the microscopic parameters on the macroscopic mechanical behavior was investigated using laboratory-scale *** field-scale pillar models(width-to-height,W/H=1,2 and 3)were calibrated based on the empirically predicted stress-strain curves of Creighton mine *** results indicated that as the W/H ratios increased,the VGBBM effectively predicted the transition from strain-softening to pseudo-ductile behavior in pillars,and explicitly captured the separated rock slabs and the V-shaped damage zones on both sides of pillars and conjugate shear bands in core zones of *** volumetric strain field revealed significant compressional deformation in core zones of *** the peak strains of W/H=1 and 2 pillars were relatively consistent,there were significant differences in the strain energy storage and release mechanism.W/H was the primary factor influencing the deformation and strain energy in the pillar *** friction coefficient of the structural plane was also an important factor affecting the pillar strength and the weakest discontinuity *** fracture surface was controlled by the discontinuity angle and the friction *** study demonstrated the capability of the VGBBM in predicting the strengths and deformation behavior of hard-rock pillars in deep mine design.

关键词： Pillar strength FDEM Voronoi tessellation Spalling Bulking

Experimental Study on Flexural Behaviour of Circular Concrete-Filled FRP-PVC Tubular Members

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沈阳建筑大学学报（自然科学版） 2012年第6期28卷 988-996页

作者： MA Shenglan LIN quan jiang Shaofei College of Civil Engineering Fuzhou University Fuzhou China 350108

An experimental investigation was conducted on the flexural behavior of FRP-PVC confined concrete circular tubular members.A total of six specimens were prepared and tested under flexural *** main parameters varied in the tests were the layer of FRP and the strengthening approach of BFRP and *** failure modes,ultimate bending capacity and stress-strain relation curves were investigated in ***,the relation model of moment(M)-curvature(φ)was studied,and on the basis of M-φ relation model,a simplified formula was presented to compute the ultimate bending moment *** results show that the external confinement of concrete specimens by FRP-PVC tubes results in enhancing the ultimate bending strength and ultimate deformation,and the ultimate bending capacity increased with the FRP ***,the reinforcement effect in CFRP is better than that in *** ultimate bending moment capacity values predicted by the presented formula agree well with the experimental results,which imply that the presented formula is applicable and efficient for prediction of the ultimate bending moment capacity as well.

关键词： FRP-PVC tubes flexural loading ultimate bending moment capacity the section flexural coefficient

Hawking Radiation of Charged Particles via Tunneling from a Cylindrically Symmetric Black Hole in Anti-de Sitter Space-Time

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Communications in Theoretical Physics 2006年第4X期46卷 643-646页

作者： YANG Shu-Zheng jiang Qing-quan LI Hui-Ling Institute of Theoretical Physics China West Normal University Nanchong 637002 China

Applying Parikh-Wilzcek＇s semi-classical quantum tunneling model, we study the Hawking radiation of charged particles as tunneling from the event horizon of a cylindrically symmetric black hole in anti-de Sitter space-time. The derived result shows that the tunneling rate of charged particles is related to the change of Bekenstein-Hawking entropy and that the radiation spectrum is not strictly pure thermal after taking the black hole background dynamical and self-gravitation interaction into account, but is consistent with the underlying unitary theory.

关键词： cylindrically symmetric black hole Bekenstein-Hawking entropy energy conservation charge conservation tunneling rate

Unloading performances and stabilizing practices for columnar jointed basalt:A case study of Baihetan hydropower station

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第6期9卷 1041-1053页

作者： Qixiang Fan Xiating Feng Wenlin Weng Yilin Fan quan jiang China Three Gorges Corporation Beijing100038China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China

The columnar jointed rock mass(CJR), composed of polygonal cross-sectional columns cut by several groups of joints in various directions, was exposed during the excavations of the Baihetan hydropower station, China. In order to investigate the unloading performances and the stability conditions during excavation of the columns, an experimental field study was performed. Firstly, on-site investigations indicated that the geotechnical problems, including rock relaxation, cracking and collapse, were the most prominent for the CJR Class I that contains intensive joint network and the smallest column *** field tests, including deformation measurement by multi-point extensometers, ultrasonic wave testing, borehole television observation and stress monitoring of rock anchors, revealed that the time-dependent relaxation of the CJRs was marked. The practical excavation experiences for the Baihetan columnar jointed rock masses, such as blasting scheme, supporting time of shotcrete and rock bolts, were presented in the excavations of the diversion tunnels. These detailed investigations and practical construction experiences can provide helpful information for similar geotechnical works in jointed rock mass.

关键词： Columnar jointed basalt Diversion tunnels Rock unloading In situ test Hydropower station

Classifying rheumatoid arthritis by Traditional Chinese Medicine Zheng: a multi-center cross-sectional study

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Journal of Traditional Chinese Medicine 2019年第3期39卷 425-432页

作者： Wang Weijie Tang Xiaopo Wang Xinchang jiang quan Fan Yongsheng Department of Rheumatology The Second Affiliated Hospital of Zhejiang Chinese Medical University Hangzhou 310005 China Department of Rheumatology Guang'anmen Hospital China Academy of Chinese Medical Sciences Beijing 100053 China Institute of Rheumatology Zhejiang Chinese Medical University Hangzhou 310053 China

OBJECTIVE:To assess the relationship between disease symptoms and traditional Chinese medicine (TCM) syndrome (Zheng) in rheumatoid arthritis (RA) ***:RA Patients were recruited in Guang'anmen Hospital,China Academy of Chinese Medical Sciences and in the Second Affiliated Hospital of Zhejiang Chinese Medical University,and diagnosed with a particular RA Zheng from their *** characteristics,self-reported symptoms,and blood samples were collected from *** data were input into EpiData and analyzed using SPSS ***:The study included 302 RA patients (age range:18-86 years).All patients were Chinese,and 85.1% were *** and fatigue triggers were reported by 8.6% of patients,followed by triggers such as childbirth (4.3%),cold (3.0%),dampness (2.0%),menopause (1.3%),and psychentonia (0.7%).The most prevalent Zheng was dampness and heat blockage (Shire Yuzu in Chinese,SRYZ),diagnosed in 39.4% of patients (119),followed by phlegm and stagnation blockage (Tanyu Bizu,TYBZ) in 21.5%,liver and kidney deficiency (Ganshen Buzu,GSBZ) in 18.5%,dual deficiency of Qi and blood (Qixue Liangxu,QXLX) in 9.6%,cold and dampness blockage (Hanshi Bizu,HSBZ) in 6%,and wind and dampness blockage (Fengshi Bizu,FSBZ) in 5%.Increased length of time since RA diagnosis was associated with the GSBZ *** diagnosed with the SRYZ Zheng had the highest disease activity *** diagnosed with the QXLX Zheng had the lowest blood platelet counts;patients diagnosed with the QXLX and HSBZ Zhengs had lower C-reactive protein levels and lower health assessment questionnaire *** diagnosed with the GSBZ and QXLX Zhengs had the highest health assessment questionnaire ***:The specific Zheng was related to RA *** findings suggest that eliminating dampness,cooling the patient,and promoting blood circulation may assist in treating severe RA.

关键词： Arthritis,rheumatoid Symptoms and signs Syndrome complex Cross-sectional studies

quantum Tunneling Radiation of Reissner-Nordstrom de Sitter Black Hole with a Global Monopole

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Communications in Theoretical Physics 2006年第3期45卷 457-460页

作者： jiang Qing-quan YANG Shu-Zheng LI Hui-Ling Institute of Theoretical Physics West China Normal University Nanchong 637002 China

Applying Parikh＇s quantum tunneling model, we study the quantum tunneling radiation of Reissne- Nordstrom de Sitter black hole with a global monopole. The result shows that the tunneling rates at the event horizon and the cosmic horizon are related to Bekenstein-Hawking entropy if we take the energy conservation into consideration, and the true radiate spectrum is not precisely thermal.

关键词： Reissner-Nordstrom de Sitter black hole global monopole energy conservation tunneling rate