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FEW-NNN: A Fuzzy Entropy Weighted Natural Nearest Neighbor Method for Flow-Based Network Traffic Attack Detection

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China Communications 2020年第5期17卷 151-167页

作者： liangchen chen Shu Gao Baoxu Liu Zhigang Lu Zhengwei Jiang School of Computer Science and Technology Wuhan University of TechnologyWuhan 430063China Institute of Information Engineering Chinese Academy of SciencesBeijing 100093China School of Applied Technology China University of Labor RelationsBeijing 100048China School of Cyber Security University of Chinese Academy of SciencesBeijing 100049China

Attacks such as APT usually hide communication data in massive legitimate network traffic, and mining structurally complex and latent relationships among flow-based network traffic to detect attacks has become the focus of many initiatives. Effectively analyzing massive network security data with high dimensions for suspicious flow diagnosis is a huge challenge. In addition, the uneven distribution of network traffic does not fully reflect the differences of class sample features, resulting in the low accuracy of attack detection. To solve these problems, a novel approach called the fuzzy entropy weighted natural nearest neighbor(FEW-NNN) method is proposed to enhance the accuracy and efficiency of flowbased network traffic attack detection. First, the FEW-NNN method uses the Fisher score and deep graph feature learning algorithm to remove unimportant features and reduce the data dimension. Then, according to the proposed natural nearest neighbor searching algorithm(NNN_Searching), the density of data points, each class center and the smallest enclosing sphere radius are determined correspondingly. Finally, a fuzzy entropy weighted KNN classification method based on affinity is proposed, which mainly includes the following three steps: 1、 the feature weights of samples are calculated based on fuzzy entropy values, 2、 the fuzzy memberships of samples are determined based on affinity among samples, and 3、 K-neighbors are selected according to the class-conditional weighted Euclidean distance, the fuzzy membership value of the testing sample is calculated based on the membership of k-neighbors, and then all testing samples are classified according to the fuzzy membership value of the samples belonging to each class;that is, the attack type is determined. The method has been applied to the problem of attack detection and validated based on the famous KDD99 and CICIDS-2017 datasets. From the experimental results shown in this paper, it is observed that the FEW-NNN method

关键词： fuzzy entropy weighted KNN network attack detection fuzzy membership natural nearest neighbor network security intrusion detection system

High-efficient removal of tetracycline in water via porous magnetic Ce/Fe photocomposite under visible light

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Journal of Rare Earths 2023年第10期41卷 1532-1540,I0003页

作者： Weihang Han Jingxuan Shou Yifan Yang liangchen chen Luping Zhang Yutong chen Xuewei Tu Dan Jin Shijie Zhang Yurong Chang Hui Zheng College of Material Chemistry and Chemical EngineeringHangzhou Normal UniversityHangzhou311121China College of Civil Engineering Zhejiang University of TechnologyHangzhou311121China Hangzhou Zeyuan Safety Technology Co. Ltd.Hangzhou311121China Hangzhou Synbest Biotech Co. Ltd.Hangzhou311121China Henan Qite New Material Co. Ltd.Zhengzhou450000China

Tetracycline is a typical antibiotic commonly used in various industries which is eco-toxic and quickly causes bacterial *** re,studying the efficient removal of tetracycline is necessary to protect the water ***,a novel Ce/Fe nanoparticle composite(1CCFO)was prepared by the sol-gel method and its removal effects of tetracycline under visible light were *** relationship between physicochemical properties of catalyst and photocatalytic degradation effects of tetracycline was analyzed based on a series of characterizations data such as X-ray diffraction(XRD),Raman spectro scopy,a vibrating sample magnetometer(VSM),scanning electron microscopy(SEM),Brunauer-Emmett-Teller(BET)method,X-ray photoelectron spectroscopy(XPS),and ultraviolet-visible(UV-Vis)*** results show that Ce/Fe photocatalyst possesses a large specific surface area,good visible light response,abundant oxygen vacancies and excellent redox performance,exhibiting good adsorption capacity,remarkable catalytic performance and *** optimal conditions for tetracycline removal were explored through orthogonal *** 88%of tetracycline can be photodegraded in 1 h under optimal *** possible decomposition pathways,main reactive oxygen species and suitable mechanism of the photocatalytic system were studied by liquid chromatography-mass spectro metry(LC-MS),an electron spin resonance(ESR)spectrometer and free radical quenching *** results show that 1CCFO has an efficient degradation effect on tetracycline under visible light,which provides a feasible method to improve the performance of 1CCFO.

关键词： Photocatalysis Degradation Tetracycline Fe-based photocatalyst Porous Rare earths

Synthesis of boron-doped diamond with laser heated diamond anvil cell

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Chinese Science Bulletin 2011年第13期56卷 1336-1339页

作者： ZHANG WeiWei chen liangchen JIN ChangQing WANG XueJin LIU YuYing LIU Jing College of Science China Agricultural University Beijing 100083 China Institute of Physics Chinese Academy of Sciences Beijing 100080 China Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 China

Boron-doped diamond has been synthesized from graphite mixed with different ratio of B 4 C at high pressure high temperature (HPHT) using laser heated diamond anvil *** starting composition was transformed to diamond compound at pressure ～9 GPa,2300-2400 K as indicated by the in-situ X-ray diffraction pattern with synchrotron radiation *** spectrum of the recovered specimen from HPHT state confirmed that boron has been doped into diamond lattice.

关键词：金刚石压腔掺硼金刚石金刚石合成激光加热原位X射线衍射拉曼光谱仪高温高压同步辐射光源

High pressure effects on the crystal structure andelectric conductivity of perovskite like (Ca/Sr)_2CuO_2Cl_2 compounds

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Chinese Science Bulletin 2008年第18期53卷 2739-2742页

作者： LIU QingQing WANG FuRen LI FengYing chen liangchen YU Richeng JIN ChangQing LI YanChun LIU Jing College of Physics Peking University Beijing 100871 China Institute of Physics Chinese Academy of Sciences Beijing 100190 China Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

The crystal structure stability as well as electric conductance of (Sr/Ca)_2CuO_2Cl_2 compound with K_2NiF_4 structure was investigated up to 31 GPa using diamond anvil technique. It seems that (Sr/Ca)_2CuO_2Cl_2 is quite stable under pressure but with obvious anisotropic compressibility. The equation of state (EOS) obtained shows relative large bulk modulus.

关键词：高压反应电导体钙钛矿型复合物循环结构同步加速器

Structural Phase Transitions of Iodine at High Pressure

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Chinese Physics Letters 1994年第2期11卷 99-101页

作者： chen liangchen ZHANG Zhiting CHE Rongzheng YU Tingnan WANG Jifang Institute of Physics Academia SinicaBeijing 100080

The compression and polymorphic phase transitions of iodine have been studied by using x-ray diffraction with a diamond anvil cell at high pressure up to *** that iodine is reactive with iron in air,a corrosion-resisting and high-strength gasket was put between the diamonds,thus the sample can be mounted at atmospheric pressure and room *** was measured in terms of the ruby fluorescence and the molybdenum diffraction as an internal pressure *** to the x-ray diffraction results,the iodine undergoes the following three structural phase transitions with pressure increasing:(1)At 21 GPa,from base centred orthorhombic phase(phase Ⅰ)to body centred orthorhombic phase(phase Ⅱ).A 2%change in volume occurs.(2)At 44 GPa,from phase II to body centred tetragonal phase(phase Ⅲ).This is a second order phase transition.(3)At 71 GPa,from phase III to fcc phase(phase Ⅳ).The volume decreases by 3%.At this time,the volume is 45%of the original one at atmospheric pressure.

关键词： temperature. transition. corrosion

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面向小样本数据的机器学习方法研究综述

计算机工程 2022年第11期48卷 1-13页

作者：陈良臣傅德印中国劳动关系学院计算机教研室北京100048 中国劳动关系学院应用统计学教研室北京100048 中国科学院信息工程研究所中国科学院网络测评技术重点实验室北京100093 武汉理工大学计算机科学与技术学院武汉430063

小样本学习是面向小样本数据的机器学习,旨在利用较少的有监督样本数据去构建能够解决实际问题的机器学习模型。小样本学习能够解决传统机器学习方法在样本数据不充分时性能严重下降的问题,可以为新型小样本任务实现低成本和快速的模型... 详细信息

小样本学习是面向小样本数据的机器学习,旨在利用较少的有监督样本数据去构建能够解决实际问题的机器学习模型。小样本学习能够解决传统机器学习方法在样本数据不充分时性能严重下降的问题,可以为新型小样本任务实现低成本和快速的模型部署,缩小人类智能与人工智能之间的距离,对推动发展通用型人工智能具有重要意义。从小样本学习的概念、基础模型和实际应用入手,系统梳理当前小样本学习的相关工作,将小样本学习方法分类为基于模型微调、基于数据增强、基于度量学习和基于元学习,并具体阐述这4大类方法的核心思想、基本模型、细分领域和最新研究进展,以及每一类方法在科学研究或实际应用中存在的问题,总结目前小样本学习研究的常用数据集和评价指标,整理基于部分典型小样本学习方法在Omniglot和Mini-ImageNet数据集上的实验结果。最后对各种小样本学习方法及其优缺点进行总结,分别从数据层面、理论研究和应用研究3个方面对小样本学习的未来研究方向进行展望。

关键词：小样本学习小样本数据机器学习深度学习数据增强

Insight into the nitrogen-vacancy center formation in type-Ib diamond by irradiation and annealing approach

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Materials Futures 2024年第4期3卷 181-191页

作者： Taiqiao Liu Fanglin Lyu Tian Shao Diwei Zou Wei Shen Yuzheng Guo Yuan Zhong Chaoyang chen liangchen Yi Zhaofu Zhang Andy H Shen The Institute of Technological Sciences Wuhan UniversityWuhan 430072People’s Republic of China Gemmological Institute China University of GeosciencesWuhan 430074People’s Republic of China School of Electrical Engineering and Automation Wuhan UniversityWuhan 430072People’s Republic of China Zhongnan Diamond Company Nanyang 473264People’s Republic of China Hubei Key Laboratory of Electronic Manufacturing and Packaging Integration Wuhan UniversityWuhan 430072People’s Republic of China

Comprehending the microscopic formation of nitrogen vacancy(NV)centers in nitrogen-doped diamonds is crucial for enhancing the controllable preparation of NV centers and quantum *** followed by annealing simulations for a type-Ib diamond with a 900 ppm concentration of isolated nitrogen is conducted along different orientations and at different annealing *** these simulations,molecular dynamics(MD)with smoothly connected potential functions are *** simulations revealed the dynamic formation process of the NV center,which was subsequently verified by first-principles calculations and *** results indicate that vacancies undergo one or multiple migrations by exchanging sites with neighboring *** are three mechanisms for the formation of NV centers:direct irradiation-induced NV formation,irradiation with further annealing to form NV and vacancy migration(VM)during the annealing ***,the results show that both VM and NV center formations are affected by *** study clarifies the formation of NV centers across multiple scales and provides a solid foundation for the targeted preparation of NV centers.

关键词： diamond NV center irradiation annealing molecular dynamics

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高速网络入侵检测中流量数据约简研究

现代电子技术 2020年第16期43卷 108-111页

作者：陈良臣武汉理工大学计算机科学与技术学院湖北武汉430063 中国劳动关系学院应用技术学院北京100048 中国科学院信息工程研究所北京100049

高速网络数据庞大且高维度,网络入侵检测系统要面对流量数据约简的问题。如何有效地实现流量数据约简是网络入侵检测系统需要研究的一个重要问题。文中首先介绍网络入侵检测中流量数据抽样和特征降维基础;然后从网络流量数据抽样和网络... 详细信息

高速网络数据庞大且高维度,网络入侵检测系统要面对流量数据约简的问题。如何有效地实现流量数据约简是网络入侵检测系统需要研究的一个重要问题。文中首先介绍网络入侵检测中流量数据抽样和特征降维基础;然后从网络流量数据抽样和网络流量特征降维两个方面总结了网络流量数据约简研究进展;最后阐述了网络入侵检测中流量数据约简研究的未来发展趋势和面临的挑战。文中所研究的流量数据约简为进一步探索网络流量测量和网络空间安全提供参考和借鉴。

关键词：网络入侵检测流量数据约简流量数据抽样流量特征降维网络安全发展趋势

Solid C_(60):Pressure Induced Phase Transitions

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Chinese Physics Letters 1993年第3期10卷 159-162页

作者： WANG Jifang WANG Lijun chen liangchen chen Hong WANG Ruju ZHANG Zhiting CHE Rongzheng ZHOU Lei Institute of Physics Academia SinicaBeijing 100080

Based on in situ high pressure x-ray diffraction with diamond anvil cell by using synchrotron radiation and pressure-quench x-ray measurement,phase transition of C_(60)under high pressured is *** maximum pressure used is 30GPa in quasi-hydrostatic case but 44GPa in nonhydrostatic *** ambient pressure,C_(60)crystal is a fcc phase with lattice parameter a=14.2086Å.It transforms from fcc to a lower symmetry phase at pressure of 13.7GPa,and then transforms to an amorphous state under pressure up to 25-30 *** amorphous state is metastable at normal ***,the experimental results are discussed.

关键词： hydrostatic amorphous phase