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Simultaneous unidirectional and bidirectional chaos-based optical communication using hybrid coupling semiconductor lasers

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science China(information sciences) 2014年第1期57卷 280-290页

作者： JIANG Ning PAN Wei LUO Bin YAN LianShan XIANG ShuiYing center for information Photonics and Communications School of Information Science and TechnologySouthwest Jiaotong University

A simultaneous unidirectional and bidirectional chaos-based optical communication scheme based on a hybrid coupling semiconductor laser system that consists of one center semiconductor laser(CSL)and multiple side semiconductor lasers(SSLs)is proposed *** this scheme,the SSLs oriented in a linear chain mutually couple with the adjacent SSLs and they are subjected to identical unidirectional injections from the CSL which is a chaotic external cavity semiconductor *** theoretically analyze the conditions for diferent types of chaos synchronization based on the symmetry operation mechanism and injection-locking mechanism,and numerically investigate the influences of operation parameters,parameter mismatch robustness,chaos pass filtering efects and communication performance of the hybrid coupling semiconductor laser *** simulation results demonstrate that with proper selection of the unidirectional and mutual coupling conditions,the SSLs can synchronize with each other isochronally and simultaneously synchronize to the CSL completely or laggardly,which enables the proposed system to achieve a unidirectional broadcasting communication from the CSL to the SSLs and a bidirectional communication among the SSLs *** proposed scheme is beneficial to the implementation of optical chaos communication networks.

关键词： semiconductor laser optical communication chaos synchronization chaos communication net-works hybrid coupling

Hyperspectral Image Classification Based on A Multi-Scale Weighted Kernel Network

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Chinese Journal of Electronics 2022年第5期31卷 832-843页

作者： SUN Le XU Bin LU Zhenyu School of Computer science Nanjing University of Information Science and Technology Engineering Research center of Digital Forensics Ministry of Education Nanjing University of Information Science and Technology School of Artificial Intelligence Nanjing University of Information Science and Technology

Recently, many deep learning models have shown excellent performance in hyperspectral image(HSI) classification. Among them, networks with multiple convolution kernels of different sizes have been proved to achieve richer receptive fields and extract more representative features than those with a single convolution kernel. However, in most networks, different-sized convolution kernels are usually used directly on multibranch structures, and the image features extracted from them are fused directly and simply. In this paper, to fully and adaptively explore the multiscale information in both spectral and spatial domains of HSI, a novel multi-scale weighted kernel network(MSWKNet) based on an adaptive receptive field is proposed. First, the original HSI cubic patches are transformed to the input features by combining the principal component analysis and one-dimensional spectral convolution. Then, a three-branch network with different convolution kernels is designed to convolve the input features, and adaptively adjust the size of the receptive field through the attention mechanism of each branch. Finally, the features extracted from each branch are fused together for the task of *** on three well-known hyperspectral data sets show that MSWKNet outperforms many deep learning networks in HSI classification.

关键词： multibranch structures image features convolution kernels multiple convolution kernels adaptive receptive field image classification feature extraction HSI classification single convolution kernel convolutional neural nets hyperspectral image classification representative features hyperspectral imaging geophysical image processing deep learning (artificial intelligence) multiscale weighted kernel network deep learning networks hyperspectral data sets three-branch network HSI cubic patches principal component analysis 1D spectral convolution different-sized convolution kernels

Lattice-based access authentication scheme for quantum communication networks

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science China(information sciences) 2024年第12期67卷 311-317页

作者： Min WANG Gui-Lu LONG Beijing Academy of Quantum information sciences State Key Laboratory of Low-dimensional Quantum Physics and Department of Physics Tsinghua University Frontier science center for Quantum information Beijing National Research center for information science and Technology

Access authentication scheme plays a foundational role in ensuring the security of communication networks. However, an access authentication scheme with high security and efficiency is still lacking in quantum communication networks. In this paper, we propose a lattice-based access authentication scheme for quantum communication networks in the manner of real-time interaction with the network control center,which could achieve properties of mutual authentication, conditional anonymity, data confidentiality, unforgeability, undeniability, and data integrity. We utilize the digital signature algorithm CRYSTALS-Dilithium and the key-establishment algorithm CRYSTALS-KYBER, both of which have been selected for standardization by the National Institute of Standards and Technology, to realize secure access authentication for users of the quantum communication networks. Specifically, in the quantum secure direct communication network, key-establishment is replaced by the verification of signatures encoded in quantum states. Our results demonstrate the feasibility of establishing a quantum-secure communication network.

关键词： quantum communication quantum network access authentication post-quantum cryptography network control center

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Research on co-propagation of QKD and classical communication by reducing the classical optical power

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Chinese Physics B 2019年第4期28卷 70-75页

作者： Ru-Shi He Mu-Sheng Jiang Yang Wang Ya-Hui Gan Chun Zhou Wan-Su Bao Henan Key Laboratory of Quantum information and Cryptography Zhengzhou information science and Technology Institute Synergetic Innovation center of Quantum information and Quantum Physics University of science and Technology of China

We investigate the crosstalk noise, especially the spontaneous Raman scattering, in the optical fiber of a copropagation system between quantum key distribution(QKD) and classical communications. Although many methods have been proposed, such as increasing the wavelength spacing and narrowband filtering technique, to suppress Raman scattering noise, these methods greatly affect the performance of QKD. One way to solve the obstacle restricting the coexistence is to decrease the classical signal power. Based on the high gain of the gated avalanche photodiode and pulse position modulation, we demonstrate that the co-propagation system works effectively with only a small effect on long-haul fibers, which has great significance for the practical widespread commercialization of QKD.

关键词： QKD co-propagation spontaneous Raman scattering gated APD modulation formats

Countermeasure against probabilistic blinding attack in practical quantum key distribution systems

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Chinese Physics B 2015年第9期24卷 111-115页

作者：钱泳君李宏伟何德勇银振强张春梅陈巍王双韩正甫 Key Laboratory of Quantum information University of Science and Technology of China Synergetic Innovation center of Quantum information & Quantum Physics University of Science and Technology of China Zhengzhou information science and Technology Institute

In a practical quantum key distribution（QKD） system, imperfect equipment, especially the single-photon detector,can be eavesdropped on by a blinding attack. However, the original blinding attack may be discovered by directly detecting the current. In this paper, we propose a probabilistic blinding attack model, where Eve probabilistically applies a blinding attack without being caught by using only an existing intuitive countermeasure. More precisely, our countermeasure solves the problem of how to define the bound in the limitation of precision of current detection, and then we prove security of the practical system by considering the current parameter. Meanwhile, we discuss the bound of the quantum bit error rate（QBER） introduced by Eve, by which Eve can acquire information without the countermeasure.

关键词： countermeasure bound single-photon detector probabilistic blinding attack quantum key distribution

A Quaternion Two-Stream R-CNN Network for Pixel-Level Color Image Splicing Localization

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Chinese Journal of Electronics 2021年第6期30卷 1069-1079页

作者： CHEN Beijing JU Xingwang GAO Ye WANG Jinwei Engineering Research center of Digital Forensics Ministry of Education Nanjing University of Information Science &Technology School of Computer Nanjing University of Information Science & Technology Jiangsu Collaborative Innovation center of Atmospheric Environment and Equipment Technology (CICAEET) Nanjing University of Information Science & Technology

Recently, Zhou et al. designed a twostream faster Region-Convolutional neural networks(RCNN) model RGB-N for color image splicing localization in CVPR2018. However, the RGB-N locates spliced regions only at block-level and ignores the entirety and inherent correlation of three channels. Therefore, an improved quaternion two-stream R-CNN model is proposed to solve these drawbacks: a mask branch combining fully convolutional network and condition random field is added for locating spliced regions at pixel-level; quaternion representation of color images is used to process color spliced images in a holistical way. In addition, feature pyramid network based on quaternion residual network is considered to extract multi-scale features for color spliced images; attention region proposal network is combined with attention mechanism and is designed to pay more attention to the spliced regions; a high-pass filter designed for image splicing detection specifically is adopted to replace steganalysis rich model filter in the RGB-N to obtain noise input for the noise stream. Experimental results on a new synthetic dataset and three standard forgery datasets demonstrate that the proposed method is superior to the existing methods in the abilities of localization, generalization, and robustness.

关键词： quaternion residual network image classification feature extraction image splicing detection convolutional neural nets RGB-N block-level color spliced images steganalysis rich model filter spliced regions noise stream feature pyramid network image segmentation attention region proposal network quaternion two-stream R-CNN network improved quaternion two-stream R-CNN model two-stream faster region-convolutional neural networks image colour analysis quaternion representation fully convolutional network object detection pixel-level color image splicing localization

Prestack Multi-Gather Simultaneous Inversion of Elastic Parameters Using Multiple Regularization Constraints

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Journal of Earth science 2018年第6期29卷 1359-1371页

作者： Shu Li Zhenming Peng Hao Wu School of Optoelectronic information University of Electronic Science and Technology of China center for information Geoscience University of Electronic Science and Technology of China School of information science and Engineering Jishou University

Inversion of Young’s modulus,Poisson’s ratio and density from pre-stack seismic data has been proved to be feasible and ***,the existing methods do not take full advantage of the prior *** considering the lateral continuity of the inversion results,these methods need to invert the reflectivity *** this paper,we propose multi-gather simultaneous inversion for pre-stack seismic ***,the total variation（TV）regularization,L1 norm regularization and initial model constraint are *** order to solve the objective function contains L1norm,TV norm and L2 norm,we develop an algorithm based on split Bregman *** main advantages of our method are as follows：（1）The elastic parameters are calculated directly from objective function rather than from their reflectivity,therefore the stability and accuracy of the inversion process can be ensured.（2）The inversion results are more in accordance with the prior geological information.（3）The lateral continuity of the inversion results are *** proposed method is illustrated by theoretical model data and experimented with a 2-D field data.

关键词： elastic parameter pre-stack inversion multi-gather regularization

Multilevel Assessment of Spatiotemporal Variability of Vegetation in Subtropical Mountain-hill Region

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Journal of Mountain science 2013年第6期10卷 1028-1038页

作者： QIU Bing-wen ZENG Can-ying TANG Zheng-hong Key Laboratory of spatial Data Mining & information Sharing of Ministry of Education Spatial Information Research Centre of Fujian Province Fuzhou University Community and Regional Planning Program University of Nebraska-Lincoln

The complex spatiotemporal vegetation variability in the subtropical mountain-hill region was investigated through a multi-level modeling framework. Three levels - parcel, landscape, and river basin levels- were selected to discover the complex spatiotemporal vegetation variability induced by climatic, geomorphic and anthropogenic processes at different levels. The wavelet transform method was adopted to construct the annual maximum Enhanced Vegetation Index and the amplitude of the annual phenological cycle based on the 16-day time series of a5om Moderate Resolution Imaging Spectroradiometer Enhanced Vegetation Index datasets during 2OOl-2OlO. Results revealed that land use strongly influenced the overall vegetation greenness and magnitude of phenological cycles. Topographic variables also contributed considerably to the models, reflecting the positive influence from altitude and slope. Additionally, climate factors played an important role： precipitation had a considerable positive association with the vegetation greenness, whereas the temperature difference had strong positive influence on the magnitude of vegetation phenology. The multilevel approach leads to a better understanding of the complex interaction of the hierarchical ecosystem, human activities and climate change.

关键词： Enhanced Vegetation Index Multilevelmodel Wavelet transform Mountain-hill region Spatiotemporal variability

MDSSD:multi-scale deconvolutional single shot detector for small objects

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science China(information sciences) 2020年第2期63卷 98-100页

作者： Lisha CUI Rui MA Pei LV Xiaoheng JIANG Zhimin GAO Bing ZHOU Mingliang XU center for Interdisciplinary information science Research Zhengzhou University

Dear editor,Object detection has always been the focus and challenge in the field of computer vision, especially the small object detection. With the arrival of deep convolutional networks (Conv Nets [1]), the perform... 详细信息

关键词： MDSSD:multi-scale deconvolutional single shot detector for small objects SSD