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Rapid Detection of Stego Images Based on Identifiable Features

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Rapid Detection of Stego Images Based on Identifiable Featur...

International Conference on advanced Communication Technology

作者： Weiwei Pang Xiangyang Luo Jie Ren Chunfang Yang Fenlin Liu State Key Laboratory of Mathematical Engineering and Advanced Computing Zhengzhou 450001 China

ISBN: (纸本)9781509016969

An increasing number of images in the Internet brings forward a higher requirement on the speed of steganalysis. For the problem of real-time detection of stego images, a rapid images steganalysis method based on identifiable features is proposed, where the identifiable features are specific character sequences left in stego images by steganography tools. The stego and cover images are distinguished according to whether the identifiable features are found in the detected images. Meanwhile, for the case of that multiple identifiable features appeared on the same location of an image, the AC (Aho-Corasick) multi-features matching algorithm is applied to improve the detection speed. In experiments, the detection method is used to detect eight steganography tools such as Invisible Secrets, E-Show, BMP Secrets and so on. The results show that the proposed steganalysis method can achieve a nearly perfect detection precision, and the detection speed can be improved significantly comparing with traditional methods (matching bytes one by one).

关键词： Steganalysis Identifiable features Steganography tools AC(Aho-Corasick) matching algorithm Stego image detection

Towards the manipulation of topological states of matter: A perspective from electron transport

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arXiv 2018年

作者： Zhang, Cheng Lu, Hai-Zhou Shen, Shun-Qing Chen, Yong P. Xiu, Faxian State Key Laboratory of Surface Physics and Department of Physics Fudan University Shanghai200433 China Collaborative Innovation Center of Advanced Microstructures Nanjing210093 China Institute for Quantum Science and Engineering Department of Physics South University of Science and Technology of China Shenzhen518055 China Shenzhen Key Laboratory of Quantum Science and Engineering Shenzhen518055 China Department of Physics University of Hong Kong Pokfulam Road Hong Kong Department of Physics and Astronomy Purdue University West LafayetteIN47907 United States Birck Nanotechnology Center Purdue University West LafayetteIN47907 United States School of Electrical and Computer Engineering Purdue University West LafayetteIN47907 United States Institute for Nanoelectronic Devices and Quantum Computing Fudan University Shanghai200433 China

The introduction of topological invariants, ranging from insulators to metals, has provided new insights into the traditional classification of electronic states in condensed matter physics. A sudden change in the topological invariant at the boundary of a topological nontrivial system leads to the formation of exotic surface states that are dramatically different from its bulk. In recent years, significant advancements in the exploration of the physical properties of these topological systems and regarding device research related to spintronics and quantum computation have been made. Here, we review the progress of the characterization and manipulation of topological phases from the electron transport perspective and also the intriguing chiral/Majorana states that stem from them. We then discuss the future directions of research into these topological states and their potential applications. Copyright © 2018, The Authors. All rights reserved.

关键词： Electron transport properties

Corrigendum to “Research on a New Signature Scheme on Blockchain”

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Security and Communication Networks 2017年第1期2017卷

作者： Chao Yuan Mi-xue Xu Xue-ming Si State Key Laboratory of Mathematical Engineering and Advanced Computing Information Engineering University Zhengzhou 450001 China

Observation of valley Landau-Zener-Bloch oscillations and pseudospin imbalance in photonic graphene

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arXiv 2018年

作者： Sun, Yong Leykam, Daniel Nenni, Stephen Song, Daohong Chen, Hong Chong, Y.D. Chen, Zhigang Department of Physics and Astronomy San Francisco State University San FranciscoCA94132 United States Moe Key Laboratory of Advanced Micro-Structured Materials School of Physics Science and Engineering Tongji University Shanghai200092 Center for Theoretical Physics of Complex Systems Institute for Basic Science Daejeon34126 Moe Key Laboratory of Weak-Light Nonlinear Photonics Teda Applied Physics Institute and School of Physics Nankai University Tianjin300457 Division of Physics and Applied Physics School of Physical and Mathematical Sciences Nanyang Technological University Singapore637371 Singapore Centre for Disruptive Photonic Technologies. Nanyang Technological University Singapore637371

We demonstrate inter-valley Bloch oscillation (BO) and Landau-Zener tunneling (LZT) in an optically-induced honeycomb lattice with a refractive index gradient. Unlike previously observed BO in a gapped square lattice, we show non-Adiabatic beam dynamics that are highly sensitive to the direction of the index gradient and the choice of the Dirac cones. In particular, a symmetry-preserving potential leads to nearly perfect LZT and coherent BO between the inequivalent valleys, whereas a symmetry-breaking potential generates asymmetric scattering, imperfect LZT, and valley-sensitive generation of vortices mediated by a pseudospin imbalance. This clearly indicates that, near the Dirac points, the transverse gradient does not always act as a simple scalar force as commonly assumed, and the LZT probability is strongly affected by the sublattice symmetry as analyzed from an effective Landau-Zener Hamiltonian. Our results illustrate the anisotropic response of an otherwise isotropic Dirac platform to real-space potentials acting as strong driving fields, which may be useful for manipulation of pseudospin and valley degrees of freedom in graphene-like systems. Copyright © 2018, The Authors. All rights reserved.

关键词： Graphene

Title: Valley-Hall photonic topological insulators with dual-band kink states

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arXiv 2018年

作者： Chen, Q. Zhang, L. He, M. Gao, F. Chen, H. Chen, Q. Zhang, L. He, M. Gao, F. Chen, H. Wang, Z. Lin, X. Yang, Y. Zhang, B. Yang, Y. Zhang, B. State Key Laboratory of Modern Optical Instrumentation College of Information Science and Electronic Engineering Zhejiang University Hangzhou310027 China Key Lab. of Advanced Micro/Nano Electronic Devices & Smart Systems of Zhejiang Electromagnetics Academy at Zhejiang University Zhejiang University Hangzhou310027 China School of Information Science and Engineering Shandong University Jinan250100 China Division of Physics and Applied Physics School of Physical and Mathematical Sciences Nanyang Technological University 21 Nanyang Link Singapore637371 Singapore Centre for Disruptive Photonic Technologies Photonics Institute Nanyang Technological University 50 Nanyang Avenue Singapore639798 Singapore

Extensive researches have revealed that valley, a binary degree of freedom (DOF), can be an excellent candidate of information carrier. Recently, valley DOF has been introduced into photonic systems, and several valley-Hall photonic topological insulators (PTIs) have been experimentally demonstrated. However, in the previous valley-Hall PTIs, topological kink states only work at a single frequency band, which limits potential applications in multiband waveguides, filters, communications, and so on. To overcome this challenge, here we experimentally demonstrate a valley-Hall PTI, where the topological kink states exist at two separated frequency bands, in a microwave substrate-integrated circuitry. Both the simulated and experimental results demonstrate the dual-band valley-Hall topological kink states are robust against the sharp bends of the internal domain wall with negligible inter-valley scattering. Our work may pave the way for multi-channel substrate-integrated photonic devices with high efficiency and high capacity for information communications and processing. Copyright © 2018, The Authors. All rights reserved.

关键词： Electric insulators

Type-I hyperbolic metasurfaces for highly-squeezed designer polaritons with negative group velocity

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arXiv 2018年

作者： Yang, Yihao Qin, Pengfei Lin, Xiao Li, Erping Wang, Zuojia Zhang, Baile Chen, Hongsheng State Key Laboratory of Modern Optical Instrumentation College of Information Science and Electronic Engineering Zhejiang University Hangzhou310027 China Key Lab. of Advanced Micro/Nano Electronic Devices & Smart Systems of Zhejiang Electromagnetics Academy at Zhejiang University Zhejiang University Hangzhou310027 China Division of Physics and Applied Physics School of Physical and Mathematical Sciences Nanyang Technological University 21 Nanyang Link Singapore637371 Singapore Centre for Disruptive Photonic Technologies Photonics Institute Nanyang Technological University 50 Nanyang Avenue Singapore639798 Singapore School of Information Science and Engineering Shandong University Qingdao266237 China

Hyperbolic polaritons in van der Waals materials and metamaterial heterostructures provide unprecedenced control over light-matter interaction at the extreme nanoscale. Here, we propose a concept of type-I hyperbolic metasurface supporting highly-squeezed magnetic designer polaritons, which act as magnetic analogues to hyperbolic polaritons in the hexagonal boron nitride (h-BN) in the first Reststrahlen band. Comparing with the natural h-BN, the size and spacing of the metasurface unit cell can be readily scaled up (or down), allowing for manipulating designer polaritons in frequency and in space at will. Experimental measurements display the cone-like hyperbolic dispersion in the momentum space, associating with an effective refractive index up to 60 and a group velocity down to 1/400 of the light speed in vacuum. By tailoring the proposed metasurface, we experimentally demonstrate an ultra-compact (with a footprint shrunken by 3600 times) integrated designer polariton circuit including high-transmission 90° sharp bending waveguides and waveguide splitters. The designed metasurface with a low profile, lightweight, and ease of access, can serve as an alternatively promising platform for emerging polaritonics, and may find many other potential applications, such as waveguiding, sensing, subdiffraction focusing/imaging, low-threshold Cherenkov radiation, strong magnetic transition enhancement, wireless energy transfer, and so forth. Copyright © 2018, The Authors. All rights reserved.

关键词： Phonons

A Traffic Classification Method Based on Wavelet Spectrum of Scatter Factor and Improved K-means

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A Traffic Classification Method Based on Wavelet Spectrum of...

2016 3rd International Conference on engineering Technology and Application（ICETA 2016）

作者： Jinlong Fei Tianpeng Wang Xinzheng He Yuefei Zhu State Key Laboratory of Mathematical Engineering and Advanced Computing Science and Technology on Communication Security Laboratory

Based on the problem that supervised machine learning requires labeled samples and fails to identify unknown traffic,the author innovatively integrates wavelet transform and K-means algorithm of unsupervised machine learning by combining the advantage of wavelet transform in solving multi-fractal network traffic and proposes a traffic identification method based on wavelet spectrum of scatter factor and improved *** method represents each stream sequence with wavelet spectrum of scatter factor,which is taken as the input of clustering *** author carries out a cluster analysis with GA K-means *** experimental result suggests that this method has an obvious superiority in stability and accuracy of classification.

关键词： traffic classification machine learning wavelet spectrum of scatter factor genetic algorithm GAK-means

Semi-Markov Network Traffic Model Based on Pareto Distribution

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Semi-Markov Network Traffic Model Based on Pareto Distributi...

2016 3rd International Conference on engineering Technology and Application（ICETA 2016）

作者： Jinlong Fei Tianpeng Wang Xinzheng He Yuefei Zhu State Key Laboratory of Mathematical Engineering and Advanced Computing Science and Technology on Communication Security Laboratory

The establishment of the network traffic model has an important significance on the research of *** the basis of existing researches,this paper proposes the improved Semi-Markov network traffic model,and re-divides the state of network traffic into idle state,normal state and busy state,and also researches the busy state of network traffic by the use of Pareto distribution,and later researches the state transition relation of Semi-Markov process on this *** experimental results show that the characteristics of the network traffic under the busy state can be well in line with the nature of Pareto distribution,and the network bandwidth utilization calculated in this way is also consistent with the actual situation,so that the model established in this paper can well describe the characteristics of network traffic.

关键词： Pareto distribution Semi-Markov process network traffic model network bandwidth utilization

An advanced Automatic Construction Method of ROP

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Wuhan University Journal of Natural Sciences 2015年第2期20卷 119-128页

作者： OUYANG Yongji WANG Qingxian PENG Jianshan ZENG Jie State Key Laboratory of Mathematical Engineering and Advanced Computing

Automatic return oriented programming （ROP） technology can effectively improve the efficiency of ROP constructed, but the existing research results still have some shortcomings including needing more address space, poor generality. In order to solve these problems, this paper presents an improved ROP auto-constructor QExtd. Firstly, we design a Turing-complete language QExtdL and provide the basis of gadgets analysis. Secondly, we represent the MI instruction and realize precise process of side-effect instructions for improving the efficiency of automatic construction. At last, we establish a three-layer language conversion mechanism, making it convenient for users to construct ROP. Theoretical and experimental data show that the QExtd automatic construction method is much better than the ROPgadget based on syntax. In addition, the proposed method succeeds in constructing gadgets of ROP with the probability of 84% for programs whose sizes are more than 20 KB and whose directory is ＂/usr/bin＂ in Ubuntu, which proves that the construction capability improves significantly.

关键词： return oriented programing （ROP） gadget automatic construction Turing-complete