Optimal Gabor Filters for Steganalysis of Content-Adaptive JPEG Steganography

( Xiaofeng Song ),( Fenlin Liu ),( Liju Chen ),( Chunfang Yang ),( Xiangyang Luo ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.1

The existing steganalysis method based on 2D Gabor filters can achieve a competitive detection performance for content-adaptive JPEG steganography. However, the feature dimensionality is still high and the time-consuming of feature extraction is relatively large because the optimal selection is not performed for 2D Gabor filters. To solve this problem, a new steganalysis method is proposed for content-adaptive JPEG steganography by selecting the optimal 2D Gabor filters. For the proposed method, the 2D Gabor filters with different parameter settings are generated first. Then, the feature is extracted by each 2D Gabor filter and the corresponding detection accuracy is used as the measure for filter selection. Next, some 2D Gabor filters are selected by a greedy strategy and the steganalysis feature is extracted by the selected filters. Last, the ensemble classifier is used to assemble the proposed steganalysis feature as well as the final steganalyzer. The experimental results show that the steganalysis feature extracted by the selected optimal 2D Gabor filters also can achieve a competitive detection performance while the feature dimensionality is reduced greatly.

Steganalysis of adaptive JPEG steganography by selecting DCT coefficients according to embedding distortion

( Xiaofeng Song ),( Fenlin Liu ),( Chunfang Yang ),( Xiangyang Luo ),( Zhenyu Li ) 한국인터넷정보학회 2015 KSII Transactions on Internet and Information Syst Vol.9 No.12

According to the characteristics of adaptive JPEG steganography which determines the changed DCT coefficients based on embedding distortion, a new steganalysis method by selecting the DCT coefficients with small distortion values is proposed. Firstly, the principle of adaptive JPEG steganography through minimizing distortion is introduced. Secondly, the practicability of selecting the changed DCT coefficients according to distortion values is studied. Thirdly, the proposed steganalysis method is given and the embedding sensitivity of the steganalysis feature extracted from the selected DCT coefficients is analyzed. Lastly, the implement processes of the proposed method are presented and analyzed in details. In the experiments, PQt, PQe and J-UNIWARD steganography are used as examples to verify the effect of the proposed steganalysis method for adaptive JPEG steganography. A serial experimental results show the detection accuracy can be improved obviously, especially when the payload is relatively low.

Detection for JPEG steganography based on evolutionary feature selection and classifier ensemble selection

( Xiaofeng Ma ),( Yi Zhang ),( Xiangfeng Song ),( Chao Fan ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.11

JPEG steganography detection is an active research topic in the field of information hiding due to the wide use of JPEG image in social network, image-sharing websites, and Internet communication, etc. In this paper, a new steganalysis method for content-adaptive JPEG steganography is proposed by integrating the evolutionary feature selection and classifier ensemble selection. First, the whole framework of the proposed steganalysis method is presented and then the characteristic of the proposed method is analyzed. Second, the feature selection method based on genetic algorithm is given and the implement process is described in detail. Third, the method of classifier ensemble selection is proposed based on Pareto evolutionary optimization. The experimental results indicate the proposed steganalysis method can achieve a competitive detection performance by compared with the state-of-the-art steganalysis methods when used for the detection of the latest content-adaptive JPEG steganography algorithms.

Electrochemical properties of Bi-Ni and Bi-Ni-Mn composite-coated electrolytic manganese dioxide

Xiaofeng Li,Zhigang Huang,Tongchi Xia,Huichao Dong,Yanghua Song 한국화학공학회 2014 Korean Journal of Chemical Engineering Vol.31 No.6

The Bi-Ni and Bi-Ni-Mn composite is separately coated on the surface of commercial electrolytic manganesedioxide (EMD) by using a simple chemical precipitation/oxidation method. The results of X-ray diffractionshow that a structure of γ-MnO2 is kept for all the coated EMD, but the intensity of their diffraction peaks is lower thanuncoated one. Both the Bi0.5-Ni0.5 and Bi0.35-Ni0.35-Mn0.3 composite benefits the discharge capacity and high-power performanceof the EMD electrodes. On the other hand, the results of scanning electron microscopy and energy dispersivespectroscopy confirm the more uniform distribution of the Bi0.15-Ni0.55-Mn0.3 composite on the surface of EMD thanthe Bi0.5-Ni0.5 one, thereby resulting in better cyclability of the electrodes. After 50 cycles at a 1C rate, the capacity retentionrate of the Bi0.15-Ni0.55-Mn0.3 composite-coated electrode reaches to 80%, which is far larger than the un-coated(49%) and the Bi0.5-Ni0.5 composite-coated (63%) one.

Out-of-plane spin polarization and antiferromagnetic spin Hall effect

Cheng Song,Xianzhe Chen,Xiaofeng Zhou,Hyunsoo Yang,Feng Pan 한국자기학회 2021 한국자기학회 학술연구발표회 논문개요집 Vol.31 No.1

The discovery of the spin Hall effect (SHE) enabled the efficient generation and manipulation of the spin current. The magnetic spin Hall effect provides a unique opportunity to control the spin current and relevant device performance with controllable magnetization. In this talk, we report the magnetic spin Hall effect both in non-collinear antiferromagnet Mn₃Pt and a collinear antiferromagnet Mn₂Au. We generate tiny out-of-plane polarized spin current (σZ) when the charge current is applied along the axis perpendicular to the magnetic mirror plane of Mn₃Pt/permalloy bilayers, but robust when the current is parallel to the magnetic mirror plane in all of the Mn₃Pt films with different orientations. In Mn₂Au, the spin currents are generated at two spin sublattices with broken spatial symmetry, and the antiparallel antiferromagnetic moments play an important role. Therefore, we term the Néel vector-dependent spin Hal effect the ‘antiferromagnetic spin Hall effect’ (AFM-SHE). The out-of-plane spins from the antiferromagnetic spin Hall effect are favorable for the efficient switching of perpendicular magnetized devices, which is required for high-density applications. The antiferromagnetic spin Hall effect adds another twist to the atomic-level control of spin currents via the antiferromagnetic spin structure.

First-principles study on electronic states of SrWO4 crystals containing F-type color centers

Min Song,Qiren Zhang,Tingyu Liu,Jigang Yin,Xiaofeng Guo,Haiyan Zhang,Xi’en Wang 한국물리학회 2009 Current Applied Physics Vol.9 No.4

The electronic structures of the SrWO4 crystals containing F-type color centers are studied within the framework of the fully relativistic self-consistent Dirac–Slater theory using a numerically discrete variational (DV-Xα) method. The calculations indicate that either F or F+ center has donor energy level within the forbidden band. The electronic transition energies from the two donor levels to the bottom of the conduction band are 1.82 eV and 2.28 eV corresponding to the 685 nm and 545 nm absorption bands, respectively. It is, therefore, concluded that the 545–685 nm absorption bands are originated from the F and F+ center in SrWO4 crystal respectively. The electronic structures of the SrWO4 crystals containing F-type color centers are studied within the framework of the fully relativistic self-consistent Dirac–Slater theory using a numerically discrete variational (DV-Xα) method. The calculations indicate that either F or F+ center has donor energy level within the forbidden band. The electronic transition energies from the two donor levels to the bottom of the conduction band are 1.82 eV and 2.28 eV corresponding to the 685 nm and 545 nm absorption bands, respectively. It is, therefore, concluded that the 545–685 nm absorption bands are originated from the F and F+ center in SrWO4 crystal respectively.

Application of advanced spectral-ratio radon background correction in the UAV-borne gamma-ray spectrometry

Xia Jigen,Song Baolin,Gu Yi,Li Zhiqiang,Xu Jie,Ge Liangquan,Zhang Qingxian,Zeng Guoqiang,Liu Qiushi,Yang Xiaofeng 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.8

The influence of the atmospheric radon background on the airborne gamma spectrum can seriously affect researchers’ judgement of ground radiation information. However, due to load and endurance, unmanned aerial vehicle (UAV)-borne gamma-ray spectrometry is difficulty installing upward-looking detectors to monitor atmospheric radon background. In this paper, an advanced spectral-ratio method was used to correct the atmospheric radon background for a UAV-borne gamma-ray spectrometry in Inner Mongolia, China. By correcting atmospheric radon background, the ratio of the average count rate of U window in the anomalous radon zone (S5) to that in other survey zone decreased from 1.91 to 1.03, and the average uranium content in S5 decreased from 4.65 mg/kg to 3.37 mg/kg. The results show that the advanced spectral-ratio method efficiently eliminated the influence of the atmospheric radon background on the UAV-borne gamma-ray spectrometry to accurately obtain ground radiation information in uranium exploration. It can also be used for uranium tailings monitoring, and environmental radiation background surveys

Multi-Task FaceBoxes: A Lightweight Face Detector Based on Channel Attention and Context Information

( Shuaihui Qi ),( Jungang Yang ),( Xiaofeng Song ),( Chen Jiang ) 한국인터넷정보학회 2020 KSII Transactions on Internet and Information Syst Vol.14 No.10

In recent years, convolutional neural network (CNN) has become the primary method for face detection. But its shortcomings are obvious, such as expensive calculation, heavy model, etc. This makes CNN difficult to use on the mobile devices which have limited computing and storage capabilities. Therefore, the design of lightweight CNN for face detection is becoming more and more important with the popularity of smartphones and mobile Internet. Based on the CPU real-time face detector FaceBoxes, we propose a multi-task lightweight face detector, which has low computing cost and higher detection precision. First, to improve the detection capability, the squeeze and excitation modules are used to extract attention between channels. Then, the textual and semantic information are extracted by shallow networks and deep networks respectively to get rich features. Finally, the landmark detection module is used to improve the detection performance for small faces and provide landmark data for face alignment. Experiments on AFW, FDDB, PASCAL, and WIDER FACE datasets show that our algorithm has achieved significant improvement in the mean average precision. Especially, on the WIDER FACE hard validation set, our algorithm outperforms the mean average precision of FaceBoxes by 7.2%. For VGA-resolution images, the running speed of our algorithm can reach 23FPS on a CPU device.

Clustering Strategy Based on Graph Method and Power Control for Frequency Resource Management in Femtocell and Macrocell Overlaid System

Hongjia Li,Xiaodong Xu,Dan Hu,Xiaofeng Tao,Ping Zhang,Song Ci,Hui Tang 한국통신학회 2011 Journal of communications and networks Vol.13 No.6

In order to control interference and improve spectrumef-ficiency in the femtocell and macrocell overlaid system (FMOS), we propose a joint frequency bandwidth dynamic division, clustering and power control algorithm (JFCPA) for orthogonal-frequencydivision-multiple access-based downlink FMOS. The overall system bandwidth is divided into three bands, and the macro-cellular coverage is divided into two areas according to the intensity of the interference from the macro base station to the femtocells, which are dynamically determined by using the JFCPA. A cluster is taken as the unit for frequency reuse among femtocells. We map the problem of clustering to the MAX k-CUT problem with the aim of eliminating the inter-femtocell collision interference, which is solved by a graph-based heuristic algorithm. Frequency bandwidth sharing or splitting between the femtocell tier and the macrocell tier is determined by a step-migration-algorithm-based power control. Simulations conducted to demonstrate the effectiveness of our proposed algorithm showed the frequency-reuse probability of the FMOS reuse band above 97.6% and at least 70% of the frequency bandwidth available for the macrocell tier, which means that the co-tier and the cross-tier interference were effectively controlled. Thus, high spectrum efficiency was achieved. The simulation results also clarified that the planning of frequency resource allocation in FMOS should take into account both the spatial density of femtocells and the interference suffered by them. Statistical results from our simulations also provide guidelines for actual FMOS planning.

Clustering Strategy Based on Graph Method and Power Control for Frequency Resource Management in Femtocell and Macrocell Overlaid System

Li, Hongjia,Xu, Xiaodong,Hu, Dan,Tao, Xiaofeng,Zhang, Ping,Ci, Song,Tang, Hui The Korea Institute of Information and Commucation 2011 Journal of communications and networks Vol.13 No.6

In order to control interference and improve spectrum efficiency in the femtocell and macrocell overlaid system (FMOS), we propose a joint frequency bandwidth dynamic division, clustering and power control algorithm (JFCPA) for orthogonal-frequency-division-multiple access-based downlink FMOS. The overall system bandwidth is divided into three bands, and the macro-cellular coverage is divided into two areas according to the intensity of the interference from the macro base station to the femtocells, which are dynamically determined by using the JFCPA. A cluster is taken as the unit for frequency reuse among femtocells. We map the problem of clustering to the MAX k-CUT problem with the aim of eliminating the inter-femtocell collision interference, which is solved by a graph-based heuristic algorithm. Frequency bandwidth sharing or splitting between the femtocell tier and the macrocell tier is determined by a step-migration-algorithm-based power control. Simulations conducted to demonstrate the effectiveness of our proposed algorithm showed the frequency-reuse probability of the FMOS reuse band above 97.6% and at least 70% of the frequency bandwidth available for the macrocell tier, which means that the co-tier and the cross-tier interference were effectively controlled. Thus, high spectrum efficiency was achieved. The simulation results also clarified that the planning of frequency resource allocation in FMOS should take into account both the spatial density of femtocells and the interference suffered by them. Statistical results from our simulations also provide guidelines for actual FMOS planning.