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基于MapReduce的HDFS数据窃取随机检测算法

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通信学报 2018年第10期39卷 11-21页

作者：高元照李炳龙陈性元信息工程大学三院河南郑州450001 密码科学技术国家重点实验室北京100094

为了解决分布式云计算存储的数据窃取检测中,出现数据量大、内部窃取难以检测的问题,以hadoop分布式文件系统(HDFS, hadoop distributed file system)为检测对象,提出了一种基于MapReduce的数据窃取随机检测算法。分析HDFS文件夹复制产... 详细信息

为了解决分布式云计算存储的数据窃取检测中,出现数据量大、内部窃取难以检测的问题,以hadoop分布式文件系统(HDFS, hadoop distributed file system)为检测对象,提出了一种基于MapReduce的数据窃取随机检测算法。分析HDFS文件夹复制产生的MAC时间戳特性,确立复制行为的检测与度量方法,确保能够检测包括内部窃取的所有窃取模式。设计适合于MapReduce任意的任务划分,同时记录HDFS层次关系的输入数据集,实现海量时间戳数据的高效分析。实验结果表明,该算法能够通过分段检测策略很好地控制漏检率和误检文件夹数量,并且具有较高的执行效率和良好的可扩展性。

关键词：随机检测算法 HDFS MapReduce MAC时间戳云计算存储

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大数据安全技术研究进展

中国科学：信息科学 2020年第1期50卷 25-66页

作者：陈性元高元照唐慧林杜学绘信息工程大学三院郑州450001 密码科学技术国家重点实验室北京100094

大数据是经济发展的新动能,社会发展的新引擎,塑造国家竞争力的战略制高点,对人民生活具有重大影响.然而随着社会对数据价值认知的提升和大数据平台建设的蓬勃发展,大数据安全问题日益成为阻碍大数据应用推广的瓶颈.同时,由于大数据技... 详细信息

大数据是经济发展的新动能,社会发展的新引擎,塑造国家竞争力的战略制高点,对人民生活具有重大影响.然而随着社会对数据价值认知的提升和大数据平台建设的蓬勃发展,大数据安全问题日益成为阻碍大数据应用推广的瓶颈.同时,由于大数据技术、框架仍在不断演变当中,研究人员对大数据安全内涵的核心认知和关键特征理解还存在差异,尚未形成相对统一的大数据安全框架.当前亟需对大数据安全技术发展现状进行梳理,为大数据安全重点问题的研究和突破提供参考.本文结合典型大数据系统技术框架,围绕大数据安全需求,构建了大数据安全技术框架.在此框架下,从大数据安全共享与可信服务、大数据平台安全和大数据安全监管3个方面系统梳理了大数据安全关键技术的研究现状,囊括了大数据业务流程和大数据系统技术框架所涉及的主要安全机制.最后总结了大数据安全技术有待解决的核心问题和发展趋势.

关键词：大数据安全安全技术框架数据安全共享平台安全安全监管

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基于多日志分析的大数据世系生成可行性证明

武汉大学学报（理学版） 2023年第6期69卷 729-738页

作者：高元照陈性元杜学绘李炳龙信息工程大学三院河南郑州450001 密码科学技术全国重点实验室北京100878

数据世系是实现大数据安全监管的有效方法。在大数据系统中,仅基于多日志分析的世系生成方法具有展现数据全生命周期完整世系视图的能力。但由于世系类型多样,该方法能否完整获取监管所需数据,即方法的理论可行性有待证明。为此,本文首... 详细信息

数据世系是实现大数据安全监管的有效方法。在大数据系统中,仅基于多日志分析的世系生成方法具有展现数据全生命周期完整世系视图的能力。但由于世系类型多样,该方法能否完整获取监管所需数据,即方法的理论可行性有待证明。为此,本文首次提出了一种形式化的证明方法。首先,对世系完整性进行了形式化定义。然后,通过对各日志包含的记录类型进行归约与关联,证明基于现有日志能否完整获取指定的世系信息;其中,提出了两种基于日志公共元素与基于程序运行原理的日志关联方法,用于对属性元素分散在多个日志中的世系类型的证明。最后,采用所提方法,证明了多日志分析方法能够用于Hadoop世系生成。

关键词：大数据世系数据生成多日志分析世系完整性证明 Hadoop Progger

Bulging Performance and Quality Control of Aluminum Alloy Tailor-welded Overlapping Sheets Based on Interface Friction

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 258-264页

作者： gao Tiejun gao Bowen LI Weijie ZHANG Jiabin College of Aerospace Engineering Shenyang Aerospace UniversityShenyang 110136China Shenyang Aerospace Xinguang Group Co.L td. Shenyang 110043China

In order to solve the problem of poor formability caused by different materials and properties in the process of tailor-welded sheets forming,a forming method was proposed to change the stress state of tailor-welded sheets by covering the tailor-welded sheets with better plastic properties overlapping *** the same time,the interface friction effect between the overlapping and tailor-welded sheets was utilized to control the stress magnitude and further improve the formability and quality of the tailor-welded *** this work,the bulging process of the tailor-welded overlapping sheets was taken as the research *** alloy tailor-welded overlapping sheets bulging specimens were studied by a combination of finite element analysis and experimental *** results show that the appropriate use of interface friction between tailor-welded and overlapping sheets can improve the formability of tailor-welded sheets and control the flow of weld seam to improve the forming *** increasing the interface friction coefficient on the side of tailor-welded sheets with higher strength and decreasing that on the side of tailor-welded sheets with lower strength,the deformation of the tailor-welded sheets are more uniform,the offset of the weld seam is minimal,the limit bulging height is maximal,and the forming quality is optimal.

关键词： tailor-welded sheets overlapping sheet bulging interface friction weld seam stress

Local magnetic moment oscillation around an Anderson impurity on graphene

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 192-201页

作者： Shuai Li Zhen Ma Jin-Hua gao School of Science Hebei University of Science and Technology School of Electronics and Information Zhengzhou University of Light Industry School of Physics and Wuhan National High Magnetic Field Center Huazhong University of Science and Technology

We theoretically investigate the spin resolved Friedel oscillation （FO） and quasiparticle interference （QPI） in graphene induced by an Anderson *** the impurity becomes magnetic,the resulted FO becomes spin dependent,which gives rise to a local magnetic moment oscillation with an envelop decaying as r-2in real space in the doping ***,at half filling,the electron density and local magnetic moment will not oscillate but decay as *** spin resolved FO has both sublattice and spin ***,the local magnetic moment decay at half filling only occurs at one sublattice of graphene,which is quite like the phenomenon observed in the STM experiment (***ález-Herrero et al.,Science 352,437 （2016）).We further give an analytic formula about such spin dependent FO based on the stationary phase ***,we study the interference of quasiparticles around the magnetic impurity by calculating the spin dependent Fourier-transformed local density of states （FT-LDOS）.Our work gives a comprehensive understanding about the local magnetic moment oscillation around an Anderson impurity on graphene.

关键词： Friedel oscillation local magnetic moment graphene Anderson impurity

Macro-mechanics and Microstructure of Nanomaterial-modified Geopolymer Concrete: A Comprehensive Review

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 204-214页

作者： WANG Tao FAN Xiangqian gao Changsheng QU Chiyu The National Key Laboratory of Water Disaster Prevention Nanjing Hydraulic Research InstituteNanjing 210024China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China School of Water Conservancy and Transportation Zhengzhou UniversityZhengzhou 450001China

We have described in detail the effects of nano-SiO_(2),nano-CaCO_(3),carbon nanotubes,and nano-Al_(2)O_(3) on geopolymer concrete from the perspectives of macro mechanics and *** existing research results show that the mechanism of nano-materials on geopolymer concrete mainly includes the filling effect,nucleation effect,and bridging effect,the appropriate amount of nano-materials can be used as fillers to reduce the porosity of geopolymer concrete,and can also react with Ca(OH)2 to produce C-S-H gel,thereby improving the mechanical properties of geopolymer *** optimum content of nano-SiO_(2) is between 1.0%and 2.0%.The optimum content of nano-CaCO_(3) is between 2.0%and 3.0%.The optimum content of carbon nanotubes is between 0.1%and 0.2%.The optimum content of nano-Al_(2)O_(3) is between 1.0%and 2.0%.The main problems existing in the research and application of nanomaterial-modified geopolymer concrete are summarized,which lays a foundation for the further application of nanomaterial in geopolymer concrete.

关键词： nanomaterials low carbon geopolymer concrete macro-mechanics microstructure

IoT Empowered Early Warning of Transmission Line Galloping Based on Integrated Optical Fiber Sensing and Weather Forecast Time Series Data

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Computers, Materials & Continua 2025年第1期82卷 1171-1192页

作者： Zhe Li Yun Liang Jinyu Wang Yang gao State Grid Henan Electric Power Company Electric Power Scientific Research Institute State Grid Henan Electric Power CompanyZhengzhou450052China

Iced transmission line galloping poses a significant threat to the safety and reliability of power systems,leading directly to line tripping,disconnections,and power *** early warning methods of iced transmission line galloping suffer from issues such as reliance on a single data source,neglect of irregular time series,and lack of attention-based closed-loop feedback,resulting in high rates of missed and false *** address these challenges,we propose an Internet of Things(IoT)empowered early warning method of transmission line galloping that integrates time series data from optical fiber sensing and weather ***,the method applies a primary adaptive weighted fusion to the IoT empowered optical fiber real-time sensing data and weather forecast data,followed by a secondary fusion based on a Back Propagation(BP)neural network,and uses the K-medoids algorithm for clustering the fused ***,an adaptive irregular time series perception adjustment module is introduced into the traditional Gated Recurrent Unit(GRU)network,and closed-loop feedback based on attentionmechanism is employed to update network parameters through gradient feedback of the loss function,enabling closed-loop training and time series data prediction of the GRU network ***,considering various types of prediction data and the duration of icing,an iced transmission line galloping risk coefficient is established,and warnings are categorized based on this ***,using an IoT-driven realistic dataset of iced transmission line galloping,the effectiveness of the proposed method is validated through multi-dimensional simulation scenarios.

关键词： Optical fiber sensing multi-source data fusion early warning of galloping time series data IoT adaptive weighted learning irregular time series perception closed-loop attention mechanism

Optimizing battery deployment: Aging trajectory prediction enabling homogenous performance grouping

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Journal of Energy Chemistry 2025年第1期100卷 565-577页

作者： Shuquan Wang Feng gao Zhan Ma Hao Tian Yusen Zhang School of Control Science and Engineering Shandong University Key Lab of Power System Intelligent Dispatch and Control of Ministry of Education Shandong University

As battery deployments in electric vehicles and energy storage systems grow, ensuring homogeneous performance across units is crucial. We propose a multi-derivative imaging fusion(MDIF) model, employing advanced imaging and machine learning to predict battery aging trajectories from minimal initial data, thus facilitating effective performance grouping before deployment. Utilizing a derivative strategy and Gramian Angular Difference Field for dimensional enhancement, the MDIF model uncovers subtle predictive features from discharge curve data after only ten cycles. The architecture includes a parallel convolutional neural network with lateral connections to enhance feature integration and *** on a self-developed dataset, the model achieves an average root-mean-square error of 0.047 Ah and an average mean absolute percentage error of 1.60%, demonstrating high precision and *** robustness is further validated through transfer learning on two publicly available datasets, adapting with minimal retraining. This approach significantly reduces the testing cycles required, lowering both time and costs associated with battery testing. By enabling precise battery behavior predictions with limited data, the MDIF model optimizes battery utilization and deployment strategies, enhancing system efficiency and sustainability.

关键词： Lithium-ion battery Battery prognostics Fusion model Convolutional neural network Transfer learning

Analysis and solution of streak effect in high dynamic range CMOS image sensors

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Science China(Information Sciences) 2025年第1期68卷 402-403页

作者： Wanbin ZHA Jiangtao XU Jinghua AO Kaiming NIE Zhiyuan gao School of Microelectronics Tianjin University Tianjin Key Laboratory of Imaging and Sensing Microelectronic Technology Tianjin University

The high dynamic range (HDR) CMOS image sensor has been widely used in many fields,such as autonomous driving and security guarding [1].The dual conversion gain (DCG)structure,which adjusts the conversion gain (CG) by changing the capacitors connected to the floating diffusion (FD)nodes in the pixel,is an effective and prevalent method for realizing HDR imaging [2].While the DCG structure can extend the dynamic range,in the practical HDR imaging process,the substantial number of photo-generated electrons in bright areas can cause significant voltage variations in the pixel *** variations affect the gray values in darker areas of the same image,leading to the streak effect [3].This study primarily investigates the streak effect caused by forward conduction current of the PN junction in DCG pixels,and proposes a circuit to suppress this effect.

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