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Reinforcement learning of non-additive joint steganographic embedding costs with attention mechanism

Science China(Information Sciences) 2023年第3期66卷 273-286页

作者： Weixuan TANG Bin LI Weixiang LI Yuangen WANG jiwu HUANG Institute of Artificial Intelligence and Blockchain Guangzhou University Guangdong Key Laboratory of Intelligent Information Processing Shenzhen Key Laboratory of Media Security Shenzhen University Shenzhen Institute of Artificial Intelligence and Robotics for Society School of Computer Science and Cyber Engineering Guangzhou University

Image steganography is the art and science of secure communication by concealing information within digital images. In recent years, the techniques of steganographic cost learning have developed rapidly. Although the existing methods can learn satisfactory additive costs, the interplay of different pixels’ embedding impacts has not been considered, so the potential of learning may not be fully exploited. To overcome this limitation, in this paper, a reinforcement learning paradigm called Jo Po L(joint policy learning) is proposed to extend the idea of additive cost learning to a non-additive situation. Jo Po L aims to capture the interactions within pixel blocks by defining embedding policies and evaluating contributions of embedding impacts on a block level rather than a pixel level. Then, a policy network is utilized to learn optimal joint embedding policies for pixel blocks through interactions with the environment. Afterwards,these policies can be converted into joint embedding costs for practical message embedding. The structure of the policy network is designed with an effective attention mechanism and incorporated with the domain knowledge derived from traditional non-additive steganographic methods. The environment is responsible for assigning rewards according to the impacts of the sampled joint embedding actions, which are evaluated by the gradient information of a neural network-based steganalyzer. Experimental results show that the proposed non-additive method Jo Po L significantly outperforms the existing additive methods against both feature-based and CNN-based steganalzyers over different payloads.

关键词： information hiding non-additive steganography steganalysis cost learning image processing

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Three new decarbonyl prenylphloroglucinols bearing unusual spirost subunits from Hypericum scabrum and their neuronal activities

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Chinese Chemical Letters 2021年第3期32卷 1173-1176页

作者： Jie Ma Guiyang Xia Yingda Zang Chuangjun Li Jianbo yang jiwu Huang Jianjun Zhang Yalun Su Aiguo Wang Dongming Zhang State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China Key Laboratory of Chinese Internal Medicine of Ministry of Education and Beijing Dongzhimen HospitalBeijing University of Chinese MedicineBeijing 100700China

Three novel polycyclic polyprenyled acylphloroglucinols,Hyperscabins A-C,were obtained from the aerial parts of Hypericum *** featured an unprecedented 5,5-spiro ketal subunit with the loss of C-2’carbonyl in the phloroglucinol *** structures were characterized by extensive spectroscopic analyses,NMR calculations with DP4+analysis,calculated electronic circular dichroism(ECD)spectra and the application of modified Mosher’s *** the assay of[^(3)H]-5-HT and[^(3)H]-NE reuptake inhibition,compounds 1 and 2 showed good inhibito ry activity(81.8%and 83.2%)in 10μmol/*** addition,compound 1 significantly increased cell viability in the experiment of oxygen and glucose deprivation/deoxygenation.

关键词： Hypericum scabrum Prenylphloroglucinols Decarbonyl 5,5-Spiroketal Neuronal effect

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Recent Advancements in Photoelectrochemical Water Splitting for Hydrogen Production

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Electrochemical Energy Reviews 2023年第1期6卷 357-402页

作者： Yibo Zhao Zhenjie Niu jiwu Zhao Lan Xue Xianzhi Fu Jinlin Long State Key Laboratory of Photocatalysis On Energy and Environment College of ChemistryFuzhou UniversityFuzhou 350116FujianChina

Sunlight is the most abundant and inexhaustible energy source on ***,its low energy density,dispersibility and intermittent nature make its direct utilization with industrial relevance challenging,suggesting that converting sunlight into chemical energy and storing it is a valuable measure to achieve global sustainable ***–neutral,clean and secondary pollution-free solar-driven water splitting to produce hydrogen is one of the most attractive avenues among all the current options and is expected to realize the transformation from dependence on fossil fuels to zero-pollution *** photosynthetic systems(APSs)based on photoelectrochemical(PEC)devices appear to be an ideal avenue to efficiently achieve solar-to-hydrogen *** this review,we comprehensively highlight the recent developments in photocathodes,including architectures,semiconductor photoabsorbers and performance optimization *** particular,frontier research cases of organic semiconductors,dye sensitization and surface grafted molecular catalysts applied to APSs based on frontier(molecular)orbital theory and semiconductor energy band theory are ***,research advances in typical photoelectrodes with the metal–insulator–semiconductor(MIS)architecture based on quantum tunnelling are also ***,we discuss the benchmarks and protocols for designing integrated tandem photoelectrodes and PEC systems that conform to the solar spectrum to achieve high-efficiency and cost-effective solar-to-hydrogen conversion at an industrial scale in the near future.

关键词： Photoelectrochemical(PEC)cells Solar water splitting Photocathodes Semiconductors Metal-insulator-semiconductor(MIS)heterostructure Tandem photoelectrodes

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Non-ambiguity of blind watermarking:a revisit with analytical resolution

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Science in China(Series F) 2009年第2期52卷 276-285页

作者： KANG XianGui HUANG jiwu ZENG WenJun SHI Yun Q. School of Information Science & Technology Sun Yat-Sen University Guangzhou 510275 China Department of CS University of Missouri-Columbia MO65211 USA Department of ECE New Jersey Institute of Technology NJ 07102 USA

Resistance to ambiguity attack is an important requirement for a secure digital rights management （DRM） system. In this paper, we revisit the non-ambiguity of a blind watermarking based on the computational indistinguishability between pseudo random sequence generator （PRSG） sequence ensemble and truly random sequence ensemble. Ambiguity attacker on a watermarking scheme, which uses a PRSG sequence as watermark, is viewed as an attacker who tries to attack a noisy PRSG sequence. We propose and prove the security theorem for binary noisy PRSG sequence and security theorem for general noisy PRSG sequence. It is shown that with the proper choice of the detection threshold Th = α n （a is a normalized detection threshold; n is the length of a PRSG sequence） and n i≥ 1.39 × m/α^2 （m is the key length）, the success probability of an ambiguity attack and the missed detection probability can both be made negligibly small thus non-ambiguity and robustness can be achieved simultaneously for both practical quantization-based and blind spread spectrum （SS） watermarking schemes. These analytical resolutions may be used in designing practical non-invertible watermarking schemes and measuring the non-ambiguity of the schemes.

关键词： watermarking ambiguity attack PRSG sequence computational indistinguishability digital rights management (DRM)

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Local pixel patterns

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Computational Visual Media 2015年第2期1卷 157-170页

作者： Fangjun Huang Xiaochao Qu Hyoung Joong Kim jiwu Huang School of Information Science and Technology Sun Yat-sen University Graduate School of Information Security Korea University College of Information Engineering Shenzhen University

In this paper, a new class of image texture operators is proposed. We firstly determine that the number of gray levels in each B × B subblock is a fundamental property of the local image texture. Thus, an occurrence histogram for each B × B sub-block can be utilized to describe the texture of the image. Moreover, using a new multi-bit plane strategy, i.e., representing the image texture with the occurrence histogram of the first one or more significant bit-planes of the input image, more powerful operators for describing the image texture can be obtained. The proposed approach is invariant to gray scale variations since the operators are, by definition,invariant under any monotonic transformation of the gray scale, and robust to rotation. They can also be used as supplementary operators to local binary patterns(LBP) to improve their capability to resist illuminance variation, surface transformations, etc.

关键词： texture multi-bit gray scale rotation

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Models for Predicting the Jet Trajectory and Intensity Drop Point of Fire Monitors

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Fluid Dynamics & Materials Processing 2021年第5期17卷 859-869页

作者： Xiaojing Hou Yongyou Cao Wenfeng Mao Zheng Wang jiwu Yuan China Petroleum and Chemical Corporation Research Institute of Safety Engineering Qingdao266000China

Two models are defined for predicting the trajectory of a foam jet originating from a fire monitor(hydrant)and the related intensity drop *** experimental framework is also defined and used accordingly to compare real-time data with the predictions of such *** mixed theoretical-experimental approach is proven to be effective for the determination of otherwise unknown coefficients which take into account several important factors such as the operation pressure,the elevation angle and the nozzle *** is shown that the mean absolute error is smaller than 20%.

关键词： Fire monitor foam extinguishing agent jet trajectory intensity of drop point

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Survey of information security

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Science in China(Series F) 2007年第3期50卷 273-298页

作者： SHEN ChangXiang ZHANG HuangGuo FENG DengGuo CAO ZhenFu HUANG jiwu Computing Technology Institute of China Navy Beijing 100841 China School of Computer Wuhan University Wuhan 430072 China Institute of Software Chinese Academy of Sciences Beijing 100080 China Department of Computer Science and Technology Shanghai Jiaotong University Shanghai 200030China Information Technology Institute Zhongshan University Guangzhou 510275 China

The 21st century is the age of information when information becomes an important strategic resource. The information obtaining, processing and security guarantee capability are playing critical roles in comprehensive national power, and information security is related to the national security and social stability. Therefore, we should take measures to ensure the information security of our country. In recent years, momentous accomplishments have been obtained with the rapid development of information security technology. There are extensive theories about information security and technology. However, due to the limitation of length, this article mainly focuses on the research and development of cryptology, trusted computing, security of network, and information hiding, etc.

关键词： information security cryptology trusted computing network security information hiding

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Carrier Cells for Delivery of Oncolytic Measles Virus into Tumors：Determinants of Efficient Loading

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Virologica Sinica 2018年第3期33卷 234-240页

作者： Chun Xu Mao Xia Gang Meng Chunyan Li Aiqin Jiang jiwu Wei Jiangsu Key Laboratory of Molecular Medicine Medical School of Nanjing University Nanjing 210093 China Drum Tower Hospital Medical School of Nanjing University Nanjing 210008 China Nanjing University Hightech Institute at Suzhou Suzhou 215123 China

Oncolytic measles virus(OMV) is a promising antitumor agent. However, the presence of anti-measles neutralizing antibodies(NAbs) against the hemagglutinin(H) protein of OMV is a major barrier to the therapeutic application of OMV in clinical practice. In order to overcome this challenge, specific types of cells have been used as carriers for *** loading strategies appear to result in different therapeutic outcomes; despite this, only few studies have reported practical ex vivo loading strategies required for effective treatment. To this end, we systematically evaluated the antitumor efficacy of OMV using different loading strategies; this involved varying the in vitro loading duration and loading dose of OMV. We found that improved oncolysis of carrier cells was achieved by a prolonged loading duration in the absence of NAbs. However, the enhanced oncolytic effect was abrogated in the presence of NAbs. Further, we found that the expression of H protein on the surface of carrier cells was predominantly determined by the loading duration rather than the loading dose. Finally, we showed that NAbs blocked viral transfer by targeting H protein prior to the occurrence of cell-to-cell interactions. Our results provide comprehensive information on the determinants of an effective loading strategy for carrier cell-based virotherapy; these results may be useful for guiding the application of OMV as an antitumor agent in clinical practice.

关键词： Oncolytic measles virus (OMV) Cell carriers Loading strategy Tumor

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Morphological, physiological and molecular characteristics of the seedless 'Hongjiangcheng' sweet orange

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Horticultural Plant Journal 2023年第3期9卷 437-449页

作者： Pei Yin Wenyu Ding Haipeng Zhang Xiao Liu Hongyan Zhang jiwu Zeng Juan Xu National Key Laboratory for Germplasm Innovation&Utilization of Horticultural Crops College of Horticulture and Forestry SciencesHuazhong Agricultural UniversityWuhan 430070China College of Horticulture Henan Agricultural UniversityZhengzhou 450002China Institute of Fruit Tree Research Guangdong Academy of Agricultural SciencesGuangzhou 510640China

Seedless citrus has become one of the breeding goals due to its high edible ratio and convenience in fresh consumption and *** this study, the ‘Hongjiangcheng' sweet orange(WT) and its seedless mutant(MT) after cobalt-60 radiation were selected to study the formation metabolism of citrus seedless phenotype. Compared with WT, the MT had altered primary metabolite contents, as indicated by GC-MS analysis. The mature pollen of the MT was mostly distorted and shrunken, and the orange mutant exhibited significantly lower fertility than the WT. Through pollination experiments and paraffin sectioning of the MT, we observed self-compatibility during pollen tube germination in situ, in combination with the absence of natural parthenocarpy and arrested zygotic embryo development at the fourth week after pollination. From transcriptomic analyses of ovules in the fourth week, 815 differentially expressed genes(DEGs) were ***, according to the annotation of gene function and qRT-PCR analysis, Cs4g10930, Cs5g21900 and orange1.1t02243 were identified as candidate genes that may govern the mechanism of seedlessness. Finally, Agrobacterium-mediated transformation verified that the overexpression of Cs4g10930 and Cs5g21900 in Newhall navel orange calli inhibited embryoid production. This study provides a better understanding of seedless formation in citrus and two key genes that may play an important role in the early selection of seedless lines in citrus breeding programs.

关键词： Citrus sinensis Seed abortion Transcriptomic sequencing Morphological aspects Candidate genes

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Characteristic Dihydroagarofuran Sesquiterpenoids with Neuroprotective Effects from the Celastraceae Plant Tripterygium wilfordii

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Chinese Journal of Chemistry 2021年第9期39卷 2547-2554页

作者： Fangyou Chen Jing Wang Yongming Luo Chuangjun Li jiwu Huang Jie Ma Dongming Zhang State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicoChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China School of Pharmacy Jiangxi University of Traditional Chinese MedicineNanchangJiangxi 330004China School of Pharmacy China Pharmaceutical UniversityNanjingJiangsu 211198China

Ten new characteristic dihydroagarofuran sesquiterpenoids and three known ones were acquired from the Celastraceae plant Tripterygium *** structure characterizations were done through spectroscopic data,while compounds 10-12 were further con firmed by single crystal *** dihydroagarofurans protected PC12 cells against H2O2-i nduced cytotoxicity as detected by CCK8 *** 5-7 and 13 sign ificantly in creased the levels of reactive oxyge n species(ROS)and superoxide dismutase(SOD),and decreased malondialdehyde(MDA)*** addition,compounds 5-7 and 13 activated the Nrf2 signaling pathway and increased Nrf2,NQO1,and HO1 expression levels in PC12 cells after H_(2)O_(2) treatment.

关键词： Tripterygium wilfordii Terpenoids Structure elucidation Neuroprotective effects X-ray diffraction

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