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Robust Image Watermarking Based on Generative Adversarial Network

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China Communications 2020年第11期17卷 131-140页

作者： Kangli Hao Guorui Feng Xinpeng Zhang School of Communication and Information Engineering Shanghai UniversityShanghai 200444China

Digital watermark embeds information bits into digital cover such as images and videos to prove the creator’s ownership of his work.In this paper,we propose a robust image watermark algorithm based on a generative adversarial network.This model includes two modules,generator and adversary.Generator is mainly used to generate images embedded with watermark,and decode the image damaged by noise to obtain the watermark.Adversary is used to discriminate whether the image is embedded with watermark and damage the image by noise.Based on the model Hidden(hiding data with deep networks),we add a high-pass filter in front of the discriminator,making the watermark tend to be embedded in the mid-frequency region of the image.Since the human visual system pays more attention to the central area of the image,we give a higher weight to the image center region,and a lower weight to the edge region when calculating the loss between cover and embedded image.The watermarked image obtained by this scheme has a better visual performance.Experimental results show that the proposed architecture is more robust against noise interference compared with the state-of-art schemes.

关键词： robust image watermark deep learning generative adversarial network convolutional neural network

Efficient outsourced extraction of histogram features over encrypted images in cloud

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Science China(Information Sciences) 2021年第3期64卷 232-234页

作者： Yanli REN Xinpeng Zhang Dawu GU Guorui FENG School of Communication and Information Engineering Shanghai University Department of Computer Science and Engineering Shanghai Jiao Tong University

Dear editor,JPEG steganalysis mainly includes feature extraction and classification [1, 2], and thus the quality of the extracted features has an important influence on the detection performance of classifiers. With the development of JPEG steganalysis, the dimension of extracted features is greatly increased for improving the detecting performance [3].

关键词： Cloud computing Outsourced computation Histogram feature Image steganalysis Symmetric encryption

Improved Lossless Data Hiding for JPEG Images Based on Histogram Modification

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Computers, Materials & Continua 2018年第6期55卷 495-507页

作者： Yang Du Zhaoxia Yin Xinpeng Zhang Key Laboratory of Intelligent Computing&Signal Processing Ministry of EducationAnhui UniversityHefei230601P.R.China Department of Computer Science Purdue UniversityWest lafayette47906USA School of Communication and Information Engineering Shanghai UniversityShanghai 200072P.R.China

This paper proposes a lossless and high payload data hiding scheme for JPEG images by histogram modification.The most in JPEG bitstream consists of a sequence of VLCs(variable length codes)and the appended bits.Each VLC has a corresponding RLV(run/length value)to record the AC/DC coefficients.To achieve lossless data hiding with high payload,we shift the histogram of VLCs and modify the DHT segment to embed data.Since we sort the histogram of VLCs in descending order,the filesize expansion is limited.The paper’s key contribution includes:Lossless data hiding,less filesize expansion in identical pay-load and higher embedding efficiency.

关键词： Lossless data hiding histogram VLC JPEG.

Reconstruction of power spectrum of primordial curvature perturbations on small scales from primordial black hole binaries scenario of LIGO/VIRGO detection

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Science China(Physics,Mechanics & Astronomy) 2023年第6期66卷 87-93页

作者： xinpeng Wang Ying-li zhang Rampei Kimura Masahide Yamaguchi School of Physics Science and Engineering Tongji UniversityShanghai200092China Institute for Advanced Study of Tongji University Shanghai200092China Kavli Institute for the Physics and Mathematics of the Universe(WPI) Chiba277-8583Japan Center for Gravitation and Cosmology Yangzhou UniversityYangzhou225009China Waseda Institute for Advanced Study Waseda UniversityTokyo169-8050Japan Department of Physics Tokyo Institute of TechnologyTokyo152-8551Japan

As a candidate bound for the Binary Black Hole(BBH) merger events detected by LIGO/Virgo, Primordial Black Holes(PBHs)provide a useful tool to investigate the primordial curvature perturbations on small scales. Using the GWTC-1 to GWTC-3 catalogs, under the scenario that PBHs originate from large primordial curvature perturbations on small scales during infiationary epoch, we for the first time reconstruct the power spectrum of primordial curvature perturbations on small scales. It is found that the value of the amplitude of the primordial power spectrum is enhanced to O(10-2)on scales O(1) pc. This may imply the validity of PBH as a possible BBH merger candidate.

关键词： primordial black hole primordial curvature perturbation gravitational wave inflation

Adaptive Backdoor Attack against Deep Neural Networks

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Computer Modeling in Engineering & Sciences 2023年第9期136卷 2617-2633页

作者： Honglu He Zhiying Zhu Xinpeng Zhang School of Computer Science Fudan UniversityShanghai200433China

In recent years,the number of parameters of deep neural networks(DNNs)has been increasing rapidly.The training of DNNs is typically computation-intensive.As a result,many users leverage cloud computing and outsource their training procedures.Outsourcing computation results in a potential risk called backdoor attack,in which a welltrained DNN would performabnormally on inputs with a certain trigger.Backdoor attacks can also be classified as attacks that exploit fake images.However,most backdoor attacks design a uniformtrigger for all images,which can be easilydetectedand removed.In this paper,we propose a novel adaptivebackdoor attack.We overcome this defect and design a generator to assign a unique trigger for each image depending on its texture.To achieve this goal,we use a texture complexitymetric to create a specialmask for eachimage,which forces the trigger tobe embedded into the rich texture regions.The trigger is distributed in texture regions,which makes it invisible to humans.Besides the stealthiness of triggers,we limit the range of modification of backdoor models to evade detection.Experiments show that our method is efficient in multiple datasets,and traditional detectors cannot reveal the existence of a backdoor.

关键词： Backdoor attack AI security DNN

Characteristics of atmospheric boundary layer structure and its influencing factors under different sea and land positions in Europe

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Earth and Planetary Physics 2023年第2期7卷 257-268页

作者： YeHui zhang xinpeng Yong HouFu Zhou HaiYang Gao Na Yang Key Laboratory of Hydrometeorological Disaster Mechanism and Warning of Ministry of Water Resources Nanjing University of Information Science and TechnologyNanjing 210044China Anhui Institute of Meteorology Sciences Anhui Key Laboratory of Atmospheric Science and Satellite Remote SensingHefei 230031China School of Atmospheric Physics Nanjing University of Information Science and TechnologyNanjing 210044China

This study identifies quantitatively the dominant contributions of meteorological factors on the development of the boundary layer heights(BLH)in the European region,based on 32 years(1990-2021)of radiosonde observations.The spatial variability of the BLH is further discussed by location,by classifying recording stations as inland,coastal,or bay.We find that the BLH in Europe varies considerably from day to night and with the seasons.Nighttime BLH is higher in winter and lower in summer,with the highest BLH recorded at coastal stations.Daytime BLH at coastal stations shows a bimodal structure with peaks in spring and autumn;at inland and bay stations,daytime BLH is lower in winter and higher in summer.The daily amplitudes of BLH at the inland and bay stations are stronger than those at coastal stations.Based on our multiple linear regression analysis and our decoupling analysis of temperature and specific humidity,we report that the development of the nighttime BLH at all types of stations is strongly dominated by the variations of surface wind speed(and,at coastal stations,wind directions).The main contributors to daytime BLH are the near-surface temperature variability at most coastal and inland stations,and,at most bay stations,the variation of the near-surface specific humidity.

关键词： atmospheric boundary layer height wind surface temperature specific humidity decoupling

On the strengthening and slip activity of Mg-3Al-1Zn alloy with pre-induced{1012¯}twins

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Journal of Magnesium and Alloys 2023年第4期11卷 1292-1307页

作者： Jie Kuang Yuqing zhang xinpeng Du Jinyu zhang Gang Liu Jun Sun State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049P.R.China The College of Optics&Photonics University of Central FloridaOrlandoFL 32826United States

{1012¯}twins were introduced into the magnesium(Mg)plate AZ31 via pre-rolling along its transverse direction.The plates,both with and without the pre-induced{1012¯}twins,were subjected to uniaxial tension along different directions.Using crystal plasticity modeling,we found that the strengthening effect of the pre-induced{1012¯}twins on the macroscopic flow stress primarily arised from the increased slip resistance caused by the boundaries,rather than the orientation hardening due to the twinning reorientation(although the latter did make its contribution in some specific loading directions).Besides,the pre-existing{1012¯}twins were found,by both experiments and simulation,to promote the activity of prismatic and pyramidalin the parent matrix of the material.Further analysis showed that the enhanced non-basal slip activity is related to the{1012¯}twin boundaries’low micro Hall-Petch slope ratios of non-basal slips to basal slip.With the critical resolved shear stress(CRSS)obtained from crystal plasticity modeling and the orientation data from EBSD,a probability-based slip transfer model was proposed.The model predicts higher slip transfer probabilities and thus lower strain concentration tendencies at{1012¯}twin boundaries than that at grain boundaries,which agrees with the experimental observation that the strain localization was primarily associated with the latter.The present findings are helpful scientifically,in deepening our understanding of how the pre-induced{1012¯}twins affect the strength and slip activity of Mg alloys,and technologically,in guiding the design of the pre-strain protocol of Mg alloys.

关键词： Mg alloy {1012¯}twins Strengthening Slip activity Micro Hall-Petch effect

Characterization of a new total heat recovery system using CaCl_(2) as working fluid:Thermal modeling and physical analysis

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Energy and Built Environment

Energy and Built Environment 2022年第2期3卷 158-170页

作者： Chenghu zhang Yibo Zhao Xiaomeng Shi xinpeng Huang School of Architecture Harbin Institute of TechnologyHarbinHeilongjiangPR China

This paper introduces a kind of open cycle absorption heat wet flue gas heat recovery system,which use CaCl_(2) as the working medium.The system will use the wet heat recovery method and combined with an efficient heat pump system for flue gas as a heat source generator.Through direct contact with the solution in the absorber,the flue gas is going to carry out gas,liquid heat transfer between heat exchanger,realization of sensible heat and latent heat step by step.As the key part of the system,absorber is established by one-dimensional steady-state heat transfer and mass transfer model.This paper uses the finite difference method to model the discrete numerical methods,and an-alyzes the characteristics of heat and mass transfer in the absorber.We obtain the concentration curves of the three kinds of working medium’s temperature and flow along the height direction.We also analyze the influence of CaCl_(2) solution parameters changes on the absorption process,parsing the reason of the temperature change by analyzing the three working medium’s energy flow trend.We found that the temperature change of flue gas is non-monotonic,which decreases gradually in the range of absorption tower height 0-0.9 m,and then increases gradually.The reason for this change is that sensible heat exchange and latent heat exchange exist between flue gas and solution.Although such a change has an impact on the efficiency of the system,it prevents the"white smoke"from condensing in the air,which effectively protects the environment.Compared with conventional LiBr absorption heat pump,the system constructed in this paper has certain advantages in latent heat recovery,flue gas heat energy utilization,energy conservation and emission reduction and economy.

关键词： Hot and wet waste gas Waste heat recovery Heat and mass transfer System features

Designed Bifunctional Ligands in Cooperative Homogeneous Gold Catalysis

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CCS Chemistry 2021年第1期3卷 1989-2002页

作者： xinpeng Cheng Liming zhang Department of Chemistry and Biochemistry University of CaliforniaSanta BarbaraCA 93106

Over the past two decades,homogeneous gold catalysis has experienced exponential development and contributed a plethora of highly valuable synthetic methods to the synthetic toolbox.Metal–ligand cooperative catalysis is a versatile strategy for achieving highly efficient and/or novel catalysis but has seldom been explored in gold chemistry.This minireview summarizes the progress we have made in developing remotely functionalized biaryl-2-ylphosphine ligands and employing them in cooperative gold catalysis that achieves excellent catalytic efficiency or realizes previously unknown reactivities.This approach also provides new venues for implementing asymmetric gold catalysis.

关键词： homogeneous gold catalysis cooperative catalysis phosphine bifunctional ligands