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Multispectral image compression and encryption method based on tensor decomposition in wavelet domain

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High Technology Letters 2024年第3期30卷 244-251页

作者： XU Dongdong DU Limin DU yunlong Electronic Information Engineering College Changchun UniversityChangchun 130022P.R.China

Multispectral image compression and encryption algorithms commonly suffer from issues such as low compression efficiency,lack of synchronization between the compression and encryption proces-ses,and degradation of intrinsic image structure.A novel approach is proposed to address these ***,a chaotic sequence is generated using the Lorenz three-dimensional chaotic mapping to initiate the encryption process,which is XORed with each spectral band of the multispectral image to complete the initial encryption of the ***,a two-dimensional lifting 9/7 wavelet transform is applied to the processed ***,a key-sensitive Arnold scrambling technique is employed on the resulting low-frequency *** effectively eliminates spatial redundancy in the multispectral image while enhancing the encryption *** optimize the compression and encryption processes further,fast Tucker decomposition is applied to the wavelet sub-band *** effectively removes both spectral redundancy and residual spatial redundancy in the multispectral ***,the core tensor and pattern matrix obtained from the decomposition are subjected to entropy encoding,and real-time chaotic encryption is implemented during the encoding process,effectively integrating compression and *** results show that the proposed algorithm is suitable for occasions with high requirements for compression and encryption,and it provides valuable insights for the de-velopment of compression and encryption in multispectral field.

关键词： multi-spectral image compression encryption Lorenz three-dimensional chaotic mapping Arnold scrambling transform fast Tucker decomposition

改进型太阳能–干法碳酸盐系统的燃煤电站灵活性碳捕集方案分析

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中国电机工程学报 2020年第14期40卷 4547-4558页

作者：杨宁孔德皓周云龙东北电力大学能源与动力工程学院吉林省吉林市132012

由于CO2排放对全球气候变化的显著影响导致燃煤电站的碳捕集问题受到广泛关注。采用干法碳酸盐(dry carbonate process,DCP)捕集低温烟气中CO2相比于传统钙循环方法(calcium cycle,CaL)具有诸多优势,且太阳能可用于提供吸附剂再生所需热... 详细信息

由于CO2排放对全球气候变化的显著影响导致燃煤电站的碳捕集问题受到广泛关注。采用干法碳酸盐(dry carbonate process,DCP)捕集低温烟气中CO2相比于传统钙循环方法(calcium cycle,CaL)具有诸多优势,且太阳能可用于提供吸附剂再生所需热量,从而取代汽轮机中低压抽汽。然而,现有研究并未改善DCP操作流程,传统的设备布置不仅增加热量损失,还增加了投资成本。研究以600MW燃煤电站尾部烟气为对象,通过去除DCP中再生器和再沸器,提出槽式太阳能集热器直接加热吸附剂的改进型方案,即吸附剂再生在集热管道中进行,不仅降低设备投资和运行成本,而且实现DCP工艺与燃煤电站解耦,消除DCP对电站蒸汽循环依赖,进一步提升系统操作的灵活性,显著增加集成系统的技术经济优势。选用EBSILON和Aspen plus构建燃煤电站与改进型方案模型,全面提升了改进型方案灵活运行过程的装置性能和年发电量,为系统的设备检修提供足够时间,缓解了瞬态气候条件的影响,研究结果将为改进型太阳能-DCP系统的应用提供有利指导。

关键词：改进型太阳能干法碳酸盐(DCP)系统燃煤电站灵活性碳捕集可行性

双谱核主元分析在气液两相流流型识别中的应用

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化工学报 2009年第4期60卷 855-863页

作者：孙斌段晓松周云龙东北电力大学能源与机械工程学院吉林省吉林市132012

针对压差波动信号的非线性和非高斯特性,提出了一种基于高阶谱和核主元分析相结合的流型识别方法。通过对气液两相流压差波动信号的双谱分析,提取了不同流型下信号的非高斯特征,以双谱分析核主元数字特征提取流型的特征,最后利用最小二... 详细信息

针对压差波动信号的非线性和非高斯特性,提出了一种基于高阶谱和核主元分析相结合的流型识别方法。通过对气液两相流压差波动信号的双谱分析,提取了不同流型下信号的非高斯特征,以双谱分析核主元数字特征提取流型的特征,最后利用最小二乘支持向量机对流型进行智能识别。实验结果表明,提取的核主元特征反映了两相流的流动状态,最小二乘支持向量机可以有效地识别水平管道内的4种典型流型,整体识别率达到95%,为流型识别提供了一种有效的方法。

关键词：气液两相流流型双谱核主元分析最小二乘支持向量机

CASIA-Iris-Africa:A Large-scale African Iris Image Database

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Machine Intelligence Research 2024年第2期21卷 383-399页

作者： Jawad Muhammad yunlong Wang Junxing Hu Kunbo Zhang Zhenan Sun School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China Center for Research on Intelligent Perception and Computing National Laboratory of Pattern RecognitionInstitute of AutomationChinese Academy of SciencesBeijing 100190China

Iris biometrics is a phenotypic biometric trait that has proven to be agnostic to human natural physiological *** on iris biometrics has progressed tremendously,partly due to publicly available iris *** databases have been available to researchers that address pressing iris biometric challenges such as constraint,mobile,multispectral,synthetics,long-distance,contact lenses,liveness detection,***,these databases mostly contain subjects of Caucasian and Asian docents with very few *** many investigative studies on racial bias in face biometrics,very few studies on iris biometrics have been published,mainly due to the lack of racially diverse large-scale databases containing sufficient iris samples of Africans in the public ***,most of these databases contain a relatively small number of subjects and labelled *** paper proposes a large-scale African database named Chinese Academy of Sciences Institute of Automation(CASIA)-Iris-Africa that can be used as a complementary database for the iris recognition community to mediate the effect of racial biases on *** database contains 28717 images of 1023 African subjects(2046 iris classes)with age,gender,and ethnicity attributes that can be useful in demographically sensitive studies of *** of specific application protocols are incorporated with the database to ensure the database’s variability and *** results of some open-source state-of-the-art(SOTA)algorithms on the database are presented,which will serve as baseline *** relatively poor performances of the baseline algorithms on the proposed database despite better performance on other databases prove that racial biases exist in these iris recognition algorithms.

关键词： African iris recognition racial bias iris image database biometrics iris recognition

Boosting Multi-modal Ocular Recognition via Spatial Feature Reconstruction and Unsupervised Image Quality Estimation

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Machine Intelligence Research 2024年第1期21卷 197-214页

作者： Zihui Yan yunlong Wang Kunbo Zhang Zhenan Sun Lingxiao He Center for Research on Intelligent Perception and Computing National Laboratory of Pattern RecognitionInstitute of AutomationChinese Academy of SciencesBeijing 100190China JD AI Research Beijing 100176China

In the daily application of an iris-recognition-at-a-distance(IAAD)system,many ocular images of low quality are *** the iris part of these images is often not qualified for the recognition requirements,the more accessible periocular regions are a good complement for *** further boost the performance of IAAD systems,a novel end-to-end framework for multi-modal ocular recognition is *** proposed framework mainly consists of iris/periocular feature extraction and matching,unsupervised iris quality assessment,and a score-level adaptive weighted fusion ***,ocular feature reconstruction(OFR)is proposed to sparsely reconstruct each probe image by high-quality gallery images based on proper feature ***,a brand new unsupervised iris quality assessment method based on random multiscale embedding robustness is *** from the existing iris quality assess-ment methods,the quality of an iris image is measured by its robustness in the embedding *** last,the fusion strategy exploits the iris quality score as the fusion weight to coalesce the complementary information from the iris and periocular *** experi-mental results on ocular datasets prove that the proposed method is obviously better than unimodal biometrics,and the fusion strategy can significantly improve therecognition performance.

关键词： Iris recognition periocular recognition spatial feature reconstruction fully convolutional network flexible matching unsupervised iris quality assessment adaptive weight fusion

流化床气固稀相流动体积空隙率的图像检测方法

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化学反应工程与工艺 2009年第5期25卷 431-436页

作者：周云龙范振儒东北电力大学能源与机械工程学院东北电力大学自动化工程学院吉林吉林132012

介绍了应用数字图像处理技术检测流化床气固稀相流动体积空隙率的方法。使用高速摄影系统,对流化床气固稀相流动过程进行实时拍摄和图像采集,利用图像处理技术对不同时刻的图像进行消噪、边缘提取、二值化、分割等处理,然后计算出图像... 详细信息

介绍了应用数字图像处理技术检测流化床气固稀相流动体积空隙率的方法。使用高速摄影系统,对流化床气固稀相流动过程进行实时拍摄和图像采集,利用图像处理技术对不同时刻的图像进行消噪、边缘提取、二值化、分割等处理,然后计算出图像中目标颗粒的周长、面积、体积等参数。统计得出每幅图像中颗粒粒径分布曲线。利用数学模型,计算出稀相流动不同时刻的体积空隙率。实验结果表明,该方法较符合实际情况、且具有较高的测量精度,可以用于气固稀相流动参数的在线检测。

关键词：稀相输送体积空隙率颗粒尺寸数字图像处理技术

A method for active deception jamming discrimination based on frequency response

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Chinese Journal of Aeronautics 2024年第6期37卷 331-347页

作者： Wenbin WEI Ruihui PENG yunlong DONG Dianxing SUN Le XU Guohong WANG Qingdao Innovation and Development Base of Harbin Engineering University Harbin Engineering University150001China Institute of Information Fusion Navy Aeronautical UniversityYantai 264001China

There are many types of radar active deception false target jamming that are highly correlated with the real *** the real and false targets under a low Signal-to-Noise Ratio(SNR)is *** solve the above problem,this article proposes a real/false target recognition method based on the features of multi-pulse joint frequency response by analyzing the differences in the scattering characteristics and modeling real target echoes as a synthesis of multi-scattering center ***,in the range-doppler domain,the real and false targets are truncated along the range dimension,and a fast Fourier transform is performed to extract the features of multi-pulse joint frequency ***,a two-channel feature fusion network is designed for real and false target ***,a Multi-Coherent Processing Interval Joint Decision Method(M-CPIJDM)based on temporal information is proposed to improve the recognition *** using the measured data show that the proposed method can well recognize real and false target signals under four jamming backgrounds:distance false target,velocity false target,distance-velocity composite false target,and forwarding dense false target.

关键词： Activedeception false target jamming Multi-scattering center echo Multi-pulse jointfrequency response feature Two-channelfeature fusion network Multi-coherent processing interval jointdecision

改进BP神经网络在气液两相流流型识别中的应用

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化工学报 2005年第1期56卷 110-115页

作者：周云龙孙斌陆军东北电力学院吉林吉林132012 华北电力大学河北保定071003

采用统计理论与分形理论相结合的方法对水平管内空气水两相流的压差波动信号进行分析 ,得到了压差均值、标准差、偏斜度、能量份额、盒维数、关联维数和Hurst指数 7个参数 ,并将上述参数作为流型的特征向量输入自适应学习率的改进BP... 详细信息

采用统计理论与分形理论相结合的方法对水平管内空气水两相流的压差波动信号进行分析 ,得到了压差均值、标准差、偏斜度、能量份额、盒维数、关联维数和Hurst指数 7个参数 ,并将上述参数作为流型的特征向量输入自适应学习率的改进BP神经网络 ,通过对训练样本的学习 ,网络可以实现对未知流型的客观识别 .仿真结果表明 :统计参数与分形参数相结合得到的流型特征向量可以很好地反映各流型之间的差异 ,网络识别率高达 93% ,并且改进后的BP网络具有收敛速度快、不易陷入局部极小的优点 .

关键词：流型识别分形参数统计参数 BP网络

玉米秸秆牺牲剂对TiO_(2)/Pt/生物炭光催化水制氢性能的影响

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农业工程学报 2021年第24期37卷 232-239页

作者：周云龙孙萌于腾王健东北电力大学能源与动力工程学院吉林132012

采用光沉积法、水热合成法制备出TiO_(2)/Pt/生物炭复合光催化剂,以玉米秸秆悬浮液作为牺牲剂,考察了不同质量分数玉米秸秆对光催化分解水制氢性能的影响。通过X射线衍射(X-ray Diffraction,XRD)、扫描电子显微镜(Scanning ElectronMicr... 详细信息

采用光沉积法、水热合成法制备出TiO_(2)/Pt/生物炭复合光催化剂,以玉米秸秆悬浮液作为牺牲剂,考察了不同质量分数玉米秸秆对光催化分解水制氢性能的影响。通过X射线衍射(X-ray Diffraction,XRD)、扫描电子显微镜(Scanning ElectronMicroscopy,SEM)、透射电子显微镜(TransmissionElectronMicroscopy,TEM)、X射线光电子能谱(X-ray Photoelectron Spectroscopy,XPS)和紫外可见漫反射光谱(UV-Visible diffuse reflectance spectra,UV-Vis DRS)等表征手段进一步论证了复合催化剂结构特征。结果表明,随着玉米秸秆质量分数的增大,光催化体系的制氢量展现出先增大后降低的变化趋势。当玉米秸秆质量分数为30%时,TiO_(2)/Pt/生物炭复合材料制氢性能最佳,制氢速率达到225μmol/(g·h),是单纯TiO_(2)/Pt的11.2倍。其原因在于玉米秸秆分子组成中含有大量的醛基自由基,在光催化过程中被激发,与空穴发生氧化反应,提高了光催化制氢效率。此外,TiO_(2)/Pt/生物炭光催化制经过5次重复利用后,制氢量仍为900μmol/g,具有较高的光稳定性。

关键词：催化剂生物炭牺牲剂制氢玉米秸秆