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Calibration based universal JPEG steganalysis

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science in china(Series F) 2009年第2期52卷 260-268页

作者： huang FangJun1,2 & huang jiwu1,2 1 {3. of {{4. science and technology,Sun Yat-Sen University,guangzhou 510275,china 2 Guangdong Key Lab. of {{4. Security technology,Sun Yat-Sen University,guangzhou 510275,china school of information science and {3. Sun Yat-Sen University Guangzhou 510275 China Guangdong Key Lab. of information Security technology Sun Yat-Sen University Guangzhou 510275 China

For steganalysis of JPEG images, features derived in the embedding domain appear to achieve a preferable performance. However, with the existing JPEG steganography, the minor changes due to the hidden secret data are not easy to be explored directly from the quantized block DCT （BDCT） coefficients in that the energy of the carrier image is much larger than that of the hidden signal. In this paper, we present an improved calibration-based universal JPEG steganalysis, where the microscopic and macroscopic calibrations are combined to calibrate the local and global distribution of the quantized BDCT coefficients of the test image. All features in our method are generated from the difference signal be- tween the quantized BDCT coefficients of the test image and its corresponding microscopic calibrated image, or calculated as the difference between the signal extracted from test image and its corresponding macroscopic calibrated image. The extracted features will be more effective for our classification. Moreover, through using the Markov empirical transition matrices, both magnitude and sign dependencies along row scanning and column scanning patterns existed in intra-block and inter-block quantized BDCT coefficients are employed in our method. Experimental results demonstrate that our proposed scheme outperforms the best effective JPEG steganalyzers having been presented.

关键词： JPEG steganography steganalysis microscopic calibration macroscopic calibration

Steganalysis of stochastic modulation steganography

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science in china(Series F) 2006年第3期49卷 273-285页

作者： HE Junhui1,2 & huang jiwu1,2 1. school of {3. {{4. and technology, Sun Yat-sen University, guangzhou 510275, china 2. Guangdong Province Key Laboratory of {3. Security, guangzhou 510275, china 1. school of information science and {3. Sun Yat-sen University Guangzhou 510275 China 2. Guangdong Province Key Laboratory of information Security Guangzhou 510275 China

Stochastic modulation steganography embeds secret message within the cover image by adding stego-noise with a specific probabilistic distribution. No method is known to be applicable to the estimation of stochastic modulation steganography. By analyzing the distributions of the horizontal pixel difference of images before and after stochastic modulation embedding, we present a new steganalytic approach to accurately estimate the length of secret message in stochastic modulation steganography. The pro- posed method first establishes a model describing the statistical relationship among the differences of the cover image, stego-image and stego-noise. In the case of stegoimage-only steganalysis, rough estimate of the distributional parameters of the cover image＇s pixel difference is obtained with the use of the provided stego-image. And grid search and Chi-square goodness of fit test are exploited to estimate the length of the secret message embedded with stochastic modulation steganography. The experimental results demonstrate that our new approach is effective for steganalyzing stochastic modulation steganography and accurately estimating the length of the secret message.

关键词： information hiding steganography steganalysis stochastic modulation statistical distribution models of difference.

Robust AVS audio watermarking

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science china(information sciences) 2010年第3期53卷 607-618页

作者： WANG Yong & huang jiwu Guangdong Key Laboratory of information Security {3., {{4. of information science and {3., Sun Yat-Sen University, guangzhou 510275, china 1. Guangdong Key Laboratory of information Security technology School of Information Science and Technology Sun Yat-Sen University Guangzhou 510275 China

Part Ⅲ of AVS (china Audio and Video Coding Standard) is the first generic audio standard proposed in china and is becoming popular in some applications. For MP3.audio, some effiorts have been made to solve the copyright pirating and malicious modifications by the way of watermarking. To our best knowledge, similar work on the AVS audio has not been explored. In this paper, we present a novel robust watermarking algorithm for AVS audio. We find that the frame type in the AVS coded process can be used as a robust feature for watermarking. Then we design a novel watermarking algorithm which is integrated into the AVS audio coding process. The watermark bits are embedded into the compressed bit stream. At the extracting end, the watermark bits can be extracted from the compressed bit stream directly. This algorithm achieves robustness to decoding/re-coding attacks, and has low computation complexity for both embedding and extracting while preserving the quality of the audio signals.

关键词： AVS audio security problems robust watermarking

Brillouin Klein space and half-turn space in three-dimensional acoustic crystals

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science Bulletin 2024年第13期69卷 2050-2058页

作者： Zhenxiao Zhu Linyun yang Jien Wu Yan Meng xiang Xi Bei Yan Jingming Chen Jiuyang Lu Xueqin {3. Weiyin Deng Ce Shang Perry Ping Shum Yihao yang Hongsheng Chen Kexin xiang Gui-Geng Liu Zhengyou Liu Zhen Gao State Key Laboratory of Optical Fiber and Cable Manufacture technology Department of Electronic and Electrical EngineeringSouthern University of Science and TechnologyShenzhen 518055China school of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China Key Laboratory of Artificial Micro-and Nanostructures of Ministry of Education and school of Physics and technology Wuhan UniversityWuhan 430072China King Abdullah University of science and technology(KAUST) Physical Science and Engineering Division(PSE)Thuwal 23955-6900Saudi Arabia Interdisciplinary Center for Quantum information State Key Laboratory of Modern Optical InstrumentationZJU-Hangzhou Global Science and Technology Innovation CenterCollege of Information Science and Electronic EngineeringZJU-UIUC InstituteZhejiang UniversityHangzhou 310027China Division of Physics and Applied Physics School of Physical and Mathematical SciencesNanyang Technological UniversitySingapore 637371Singapore Institute for Advanced Studies Wuhan UniversityWuhan 430072China

The Bloch band theory and Brillouin zone(BZ)that characterize wave-like behaviors in periodic mediums are two cornerstones of contemporary physics,ranging from condensed matter to topological *** theoretical breakthrough revealed that,under the projective symmetry algebra enforced by artificial gauge fields,the usual two-dimensional(2D)BZ(orientable Brillouin two-torus)can be fundamentally modified to a non-orientable Brillouin Klein bottle with radically distinct manifold ***,the physical consequence of artificial gauge fields on the more general three-dimensional(3.)BZ(orientable Brillouin three-torus)was so far ***,we theoretically discovered and experimentally observed that the fundamental domain and topology of the usual 3. BZ can be reduced to a non-orientable Brillouin Klein space or an orientable Brillouin half-turn space in a 3. acoustic crystal with artificial gauge *** experimentally identify peculiar 3. momentum-space non-symmorphic screw rotation and glide reflection symmetries in the measured band ***,we experimentally demonstrate a novel stacked weak Klein bottle insulator featuring a nonzero Z2 topological invariant and self-collimated topological surface states at two opposite surfaces related by a nonlocal twist,radically distinct from all previous 3. topological *** discovery not only fundamentally modifies the fundamental domain and topology of 3. BZ,but also opens the door towards a wealth of previously overlooked momentum-space multidimensional manifold topologies and novel gaugesymmetry-enriched topological physics and robust acoustic wave manipulations beyond the existing paradigms.

关键词： Momentum-space non-symmorphic symmetry Brillouin Klein space and half-turn space Acoustic Klein bottle insulator Self-collimated topological surface states

Transport network and flow mechanism of shallow ore-bearing magma in Tongling ore cluster area

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science china Earth sciences 2006年第4期49卷 397-407页

作者： DENG Jun1,2, WANG Qingfei1,2 , huang Dinghua3., WAN Li4. yang Liqiang1,2 & GAO Bangfei1,2 1. State Key Laboratory of Geological Processes and Mineral Resources, {3. University of Geo{4.s, Beijing 100083. {3. 2. Key Laboratory of Lithosphere Tectonics and Lithoprobing technology of Ministry of Education, {3. University of Geo- {4.s, Beijing 100083. {3. 3. Faculty of Earth {4.s, {3. University of Geo{4.s, Wuhan 4.0074. {3. 4. school of Mathematics and {14. {4., guangzhou University, guangzhou 5104.5, {3. 1. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China 2. Key Laboratory of Lithosphere Tectonics and Lithoprobing technology of Ministry of Education China University of Geosciences Beijing 100083 China 3. Faculty of Earth sciences China University of Geosciences Wuhan 430074 China 4. school of Mathematics and information {3. Guangzhou University Guangzhou 510405 China

Abundant studies revealed that shallow intrusions of the Yanshanian epoch resulted in the mass mineralization of the Tongling region. Various evidences showed there existed a concealed magma chamber at ?10 km depth in the middle part of this region during Yanshanian epoch, from which the ore-forming magma was generated and then transported to the superficial layer. Yet the transport network and flow mechanism of the shallow ore-bearing magma, the key problem associ- ated with ore-forming process, was relatively little focused on. Integrate analysis of structural me- chanics, statistical fractal and geological facts suggested that NE trending high-angle fold-related thrust faults and the tessellated basement ones served as the main pathways for the shallow magma’s transporting, moreover, the saddle void spaces among adjacent strata in the folds upon this fault system provided the place for magma’s emplacement. So the folds in the upper part and faults in the lower part of the upper crust constituted the fluid’s transport and emplacement network. During the deformation of geologic body with multi-layer structure, the layers in the upper part tended to fold when received the jacking stress from the lower part, while the lower one inclined to fault undergoing loads of the upper part. And the producing probability of this structure assemblage was highly in- creased in the condition, such as in the Tongling area, that the mechanic rigidity of the lower layers was stronger than that of the upper ones. For the pre-existence of fluid-conducting network, the top magma with high volatile in the magma chamber transported rapidly to the superficial layer in dyking pattern, located in the void spaces of folds, filled and reconstructed them. The sudden drop of pres- sure caused the fluid unmixing from the magma and mass ore-forming elements concentration. Pulse activity of the dyking may be the principal reason why magmatic bodies in the Tongling area were spatially-temporally con

关键词： Tongling, structural network, magma intrusion, fractal, dyke.

Modelling and simulation study on dynamic pollution accumulation process of composite insulator

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High Voltage 2024年第3期9卷 601-613页

作者： Zhongyi yang Dongxiong Liu xiangjun Zeng Caijin Fan Xin yang Yafei {3. school of Electrical and information Engineering Changsha University of Science and TechnologyChangshaChina State Key Laboratory of HVDC Electric Power Research InstituteCSGGuangzhouChina

With the widespread application of composite insulators in transmission lines,exploring the accumulation mechanism of pollution particles on composite insulator surfaces is of importance to ensure the safe and steady operation of the power *** the current theoretical shortcomings,this study categorises the accumulation process of particles on the insulator surface into three stages,namely‘spatial motion’,‘surface collision’,and‘surface motion’.The motion and rotation velocities in a multi-physics field are calculated in the spatial motion *** the surface collision stage,a parameter called‘neck height’is introduced to determine the optimum mechanics theory,and the normal deposition criterion is *** the surface motion stage,the sliding displacement and rolling displacement on the surface are calculated based on the rotation speed of the particles.A dynamic pollution accumulation model of the composite insulator is estab-lished based on the normal deposition criterion and tangential ***,numerical simulations are performed by using the finite element *** results show that the proposed model agrees with the actual insulator pollution accu-mulation,and the deposition model is still applicable for various types of composite insulators operating in different applied *** deposition probability of particles increases with the increasing particle *** the surface motion stage,particle displacement increases with particle size and wind velocity.

关键词： composite displacement dynamic

An Aggregation Composition Compensation Method Based on Paired Net

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International Journal of Automation and computing 2012年第5期9卷 530-538页

作者： Xiao-Yong Mei 1,2 Yi-Yan Fan 2 Chang-Qin huang 3.Ai-Jun Jiang 1 Shi-Xian Li 1 1 school of information {3. and {{4.,Sun Yat-sen University,guangzhou 510006,china 2 school of Computer {3. and {{4.,Hunan University of Arts and {3.,Changde {4.5000,china 3.Department of Electrical Engineering and Computer {3.,University of California,Irvine,CA,92697,USA 1. school of information science and {3. Sun Yat-sen University Guangzhou 510006 China 2. school of Computer science and technology Hunan University of Arts and Science Changde 415000 China 3. Department of Electrical Engineering and Computer science University of California Irvine CA 92697 USA

With regard to the failure and cancellation of business logic of web services composition(WSC),this paper propose a novel web services transaction compensation mechanism based on paired net which can dynamically establish agile compensation-triggered process(CSCP-Nets),and satisfy prospective compensation *** related execution semantics of five usual composition compensation patterns based on paired net are analyzed in the situations of successful execution,failure compensation and failure *** net based application of trip reservation process(TRP) shows that it is feasible.

关键词： Web services composition failure handling composition compensation execution semantic analysis paired net

A Federated Learning Framework with Blockchain-Based Auditable Participant Selection

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Computers, Materials & Continua 2024年第6期79卷 5125-5142页

作者： huang Zeng Mingtian Zhang Tengfei Liu Anjia yang College of Cyber Security Jinan UniversityGuangzhou510632China

Federated learning is an important distributed model training technique in Internet of Things(IoT),in which participant selection is a key component that plays a role in improving training efficiency and model *** module enables a central server to select a subset of participants to performmodel training based on data and device *** doing so,selected participants are rewarded and actively perform model training,while participants that are detrimental to training efficiency and model accuracy are ***,in practice,participants may suspect that the central server may have miscalculated and thus not made the selection *** lack of trustworthiness problem,which can demotivate participants,has received little *** problem that has received little attention is the leakage of participants’private information during the selection *** will therefore propose a federated learning framework with auditable participant *** supports smart contracts in selecting a set of suitable participants based on their training loss without compromising the *** the possibility of malicious campaigning and impersonation of participants,the framework employs commitment schemes and zero-knowledge proofs to counteract these malicious ***,we analyze the security of the framework and conduct a series of experiments to demonstrate that the framework can effectively improve the efficiency of federated learning.

关键词： Federated learning internet of things participant selection blockchain auditability privacy

Online soft measurement for wastewater treatment system based on hybrid deep learning

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Frontiers of Environmental science & Engineering 2024年第2期18卷 77-89页

作者： Wenjie Mai Zhenguo Chen Xiaoyong Li Xiaohui Yi Yingzhong Zhao Xinzhong He xiang Xu Mingzhi huang SCNU Environmental Research Institute Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety&MOE Key Laboratory of Theoretical Chemistry of EnvironmentSchool of EnvironmentSouth China Normal UniversityGuangzhou 510006China Fujian Environmental Protection Design Institute Co.Ltd. Fuzhou 350000China Huashi(Fujian)Environment technology Co.Ltd. Quanzhou362001China SCNU Qingyuan Institute of science and technology Innovation Co.Ltd. Qingyuan 511517China Econ technology Co.Ltd. Yantai 265503China

The existing automated wastewater treatment control systems encounter challenges such as the utilization of specialized testing instruments, equipment repair complications, high operational costs, substantial operational errors, and low detection accuracy. An effective soft measure model offers a viable approach for real-time monitoring and the development of automated control in the wastewater treatment process. Consequently, a novel hybrid deep learning CNN-BNLSTM-Attention (CBNLSMA) model, which incorporates convolutional neural networks (CNN), bidirectional nested long and short-term memory neural networks (BNLSTM), attention mechanisms (AM), and Tree-structure Parzen Estimators (TPE), has been developed for monitoring effluent water quality during the wastewater treatment process. The CBNLSMA model is divided into four stages: the CNN module for feature extraction and data filtering to expedite operations;the BNLSTM module for temporal data’s temporal information extraction;the AM module for model weight reassignment;and the TPE optimization algorithm for the CBNLSMA model’s hyperparameter search optimization. In comparison with other models (TPE-CNN-BNLSTM, TPE-BNLSTM-AM, TPE-CNN-AM, PSO-CBNLSTMA), the CBNLSMA model reduced the RMSE for effluent COD prediction by 25.4., decreased the MAPE by 3..9%, and enhanced the R2 by 14.9%. For the effluent SS prediction, the CBNLSMA model reduced the RMSE by 26.4., the MAPE by 21.0%, and improved the R2 by 3..7% compared to other models. The simulation results demonstrate that the proposed CBNLSMA model holds significant potential for real-time effluent quality monitoring, indicating its high potential for automated control in wastewater treatment processes.

关键词： Prediction model Soft measurement CNN-BNLSTM-AM model TPE optimization algorithm