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Multi-Layer Reconstruction Errors Autoencoding and Density Estimate for Network Anomaly Detection

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Computer Modeling in Engineering & Sciences 2021年第7期128卷 381-397页

作者： ruikun li Yun li Wen He lirong Chen Jianchao Luo University of Electronic Science and Technology of China Chengdu611730China Guangdong Weichen Information Technology Co. Ltd.Guangzhou510000China Chongqing Changan Automobile Corporation Chongqing400000China

Anomaly detection is an important method for intrusion *** recent years,unsupervised methods have been widely researched because they do not require *** example,a nonlinear autoencoder can use reconstruction errors to attain the discrimination *** method is not effective when the model complexity is high or the data contains *** method for detecting the density of compressed features in a hidden layer can be used to reduce the influence of noise on the selection of the threshold because the density of abnormal data in hidden layers is smaller than normal ***,compressed features may lose some of the high-dimensional distribution information of the original *** this paper,we present an efficient anomaly detection framework for unsupervised anomaly detection,which includes network data capturing,processing,feature extraction,and anomaly *** employ a deep autoencoder to obtain compressed features and multi-layer reconstruction errors,and feeds them the same to the Gaussian mixture model to estimate the *** proposed approach is trained and tested on multiple current intrusion detection datasets and real network scenes,and performance indicators,namely accuracy,recall,and F1-score,are better than other autoencoder models.

关键词： Anomaly detection deep autoencoder density estimate

Effects of in-situZrB_2 nanoparticles and scandium on microstructure and mechanical property of 7N01 aluminum alloy

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Journal of Rare Earths 2024年第3期42卷 612-620,I0007页

作者： Xizhou Kai Yuhui Wang ruikun Chen Yanjie Peng Anjun Shi Ran Tao Xiangfeng liang Guirong li Gang Chen Xiaojing Xu Yutao Zhao School of Material Science and Engineering Jiangsu UniversityZhenjiang212013China Institute for Advanced Manufacturing and Modern Equipment Technology Jiangsu UniversityZhenjiang212013China

In this study, the in-situ synthesized ZrB_(2) nanoparticles and rare earth Sc were introduced to enhance the strength and ductility of 7N01 aluminum alloy, via the generation of high-melting and uniform nanodispersoids. The microstructure and mechanical property evolution of the prepared composites and the interaction between ZrB_(2) and Sc were studied in detail. The microstructure investigation shows that the introduction of rare earth scandium(Sc) can promote the distribution of ZrB_(2) nanoparticles, by improving their wettability to the Al melt. Meanwhile, the addition of rare earth Sc also modifies the coarse Al Zn Mg Mn Fe precipitated phases, refines the matrix grains and generates high-melting Al_3(Sc,Zr)/Al_3Sc nanodispersoids. Tensile tests of the composites show that with the combinatorial introduction of ZrB_(2) and Sc, the strength and ductility of the composites are improved simultaneously compared with the corresponding 7N01 alloy, ZrB_(2) /7N01 composite and Sc/7N01 alloy. And the optimum contents of ZrB_(2) and Sc are 3 wt% and 0.2 wt% in this study. The yield strength, ultimate strength and elongation of(3 wt% ZrB_(2) +0.2 wt% Sc)/7N01 composite are 477 MPa, 506 MPa and 9.8%, increased about 18.1%, 12.2%and 38% compared to 7N01 alloy. Furthermore, the cooperation strengthening mechanisms of ZrB_(2) and Sc are also discussed.

关键词： 7N01 aluminum alloy In-situ ZrB_(2)nanoparticles Rare earth Sc Microstructure Mechanical property Mechanism

Material basis and pharmacodynamic mechanism of YangshenDingzhi granules in the intervention of viral pneumonia:Based on serum pharmacochemistry and network pharmacology

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Animal Models and Experimental Medicine 2024年第3期7卷 259-274页

作者： Huirong Xu Meiyue Dong ruikun Du Chengcheng Zhang Zinuo Chen Guangyu Tian Qinghua Cui Kejian li College of Traditional Chinese Medicine Shandong University of Traditional Chinese MedicineJinanChina Innovative Institute of Chinese Medicine and Pharmacy Shandong University of Traditional Chinese MedicineJinanChina Qingdao Academy of Chinese Medical Sciences Shandong University of Traditional Chinese MedicineQingdaoChina College of Pharmacy Shandong University of Traditional Chinese MedicineJinanChina

Background:YangshenDingzhi granules(YSDZ)are clinically effective in preventing and treating *** present study elucidates the underlying mechanism of YSDZ intervention in viral pneumonia by employing serum pharmacochemistry and network ***:The chemical constituents of YSDZ in the blood were examined using ultraperformance liquid chromatography-quadrupole/orbitrap high-resolution mass spectrometry(UPLC-Q-Exactive Orbitrap MS).Potential protein targets were obtained from the SwissTargetPrediction database,and the target genes associated with viral pneumonia were identified using GeneCards,DisGeNET,and Online Mendelian Inheritance in Man(OMIM)*** intersection of blood component-related targets and disease-related targets was determined using Venny ***-protein interaction networks were constructed using the STRING *** Metascape database was employed to perform enrichment analyses of Gene Ontology(GO)functions and Kyoto Encyclopedia of Genes and Genomes(KEGG)signaling pathways for the targets,while the Cytoscape 3.9.1 software was utilized to construct drug-component-disease-target-pathway ***,in vitro and in vivo experiments were performed to establish the therapeutic effectiveness of YSDZ against viral ***:Fifteen compounds and 124 targets linked to viral pneumonia were detected in *** these,MAPK1,MAPK3,AKT1,EGFR,and TNF play significant *** vitro tests revealed that the medicated serum suppressed the replication of H1N1,RSV,and SARS-CoV-2 ***,in vivo testing analysis shows that YSDZ decreases the viral load in the lungs of mice infected with RSV and ***:The chemical constituents of YSDZ in the blood may elicit therapeutic effects against viral pneumonia by targeting multiple proteins and pathways.

关键词： network pharmacology pharmacodynamical material basis serum pharmacochemistry viral pneumonia YangshenDingzhi granules

Coupling metal-organic frameworks and wood-based carbon for water remediation

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Nano Research 2024年第6期17卷 5661-5669页

作者： Akhter Zia Manish Neupane Aidan McGlone Rui He ruikun Xin Yifeng liu Qiangu Yan Jinwu Wang ling li Zhiyong Cai Pei Dong Yingchao Yang Department of Mechanical Engineering University of MaineOronoME 04469USA Department of Mechanical and Aerospace Engineering University of MissouriColumbiaMO 65211USA Department of Mechanical Engineering George Mason UniversityFairfaxVA 22030USA Department of Civil and Environmental Engineering Rice UniversityHoustonTX 77005USA Department of Materials Science and NanoEngineering Rice UniversityHoustonTX 77005USA Forest Products Laboratory USDAMadisonWI 53726USA School of Forestry Resources University of MaineOronoME 04469USA

Fresh and clean water is highly demanded throughout the *** effectively address the need,nanomaterials enabled nanotechnology has been explored as a means of more efficient,reliable,and environmentally friendly approach towards water treatment *** concern in adopting nanomaterials is how to retrieve them from water body to avoid secondary *** this work,the earth abundant and sustainable wood,e.g.,basswood,was selected and carbonized into porous carbon as host skeleton,and metal-organic frameworks(MOFs),e.g.,MOF-199 with extremely high surface area,were grown throughout all channels in the porous basswood *** the traditional organic pollutant,methyl orange(MO),the combination of MOFs and basswood carbon(MOFs@carbon)demonstrates a remarkable adsorption capacity,which is 243%and 454%higher than basswood carbon and MOF-199,*** an outstanding adsorption performance originates from that the positively charged carbon pulls MO molecules close to carbon surface,leading to a high MO molecule concentration,and then the concentration gradient drives the MO molecules to be stored inside MOFs,functioning like *** findings highlight the potential application of coupled MOFs and biomass carbon in addressing water remediation.

关键词： metal-organic framework(MOF)-199 basswood carbon MOFs@carbon methyl orange

MAGNETIC DOMAIN STRUCTURE AND RELATED MAGNETIC PROPERTIES OF(NdPr)_(16)Fe_(76)B_8 PERMANENT MAGNET

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Acta Metallurgica Sinica(English Letters) 1989年第8期2卷 127-132页

作者： WANG ruikun SUN lihong li Dongpei YING Qiming

The magnetic domain structure and related magnetic properties of (NdPr)_(16)Fe_(76)B_8 permanent magnet have been studied by colloid-SEM *** thermally demagnetized state,the ma- trix grains in the magnet generally exhibit multidomain structure,i.e.,180° plate-like indi- vidual domain and a few spike-like or maze-like *** average width of the domain measured was 1.5μ*** size of single-domain was observed to be generally about 1μm and only a few up to 3μ*** results calculated are:the domain wall energy γ=36 MJ/m^2,the exchange constant A=4.5×10^(-11)J/m,the domain wall width δ=15.7nm, and the critical grain diameter of single-domain D_c=0.5μ*** dependence of high magnet- ic field gradient at grain boundaries in different magnetization directions in the adjacent mag- netic domains located on both sides of grain boundaries and the effect of microstructure on the values of K,A and δ were discussed.

关键词： Nd-Fe-B permanent magnet domain structure magnetic properties

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凝汽器下沉对机组经济性的影响及其优化机制

广东电力 2023年第10期36卷 114-120页

作者：李飞梁清鹤刘然李瑞坤国家能源集团宁夏电力有限公司宁夏银川750400 国能浙能宁东发电有限公司宁夏灵武751400 国能平罗发电有限公司宁夏石嘴山753406

为推进常规火电机组一次直流冷端系统的运行优化,提高其运行的经济性,有必要参考核电常规岛厂房局部下沉布置方案,研究常规机组凝汽器下沉对其系统经济性的优化机制。首先,综合凝汽器局部下沉对机组冷端系统主要设备的造价、运行费用及... 详细信息

为推进常规火电机组一次直流冷端系统的运行优化,提高其运行的经济性,有必要参考核电常规岛厂房局部下沉布置方案,研究常规机组凝汽器下沉对其系统经济性的优化机制。首先,综合凝汽器局部下沉对机组冷端系统主要设备的造价、运行费用及相应工程量的影响,建立采用直流冷却的常规发电机组凝汽器局部下沉的优化模型;然后,以年总费用最小为目标,对冷端优化、年固定分摊率、潮水位等参数进行敏感性分析,结果表明下沉优化结果仅受潮位影响,与冷端优化参数及年固定分摊率无关;最后,综合考虑项目建设费用及项目运行20年期间经济性,对比常规布置方案与最佳下沉布置方案,给出某单台机组项目全生命周期(20年)的节约费用:相对常规方案,采用凝汽器局部下沉布置最优方案(深度2.31 m),单台机组项目全生命周期可节约2162.7万元。所研结果为滨海电站直流冷却发电机组凝汽器下沉优化决策提供了基础。

关键词：冷端优化凝汽器下沉经济性影响机制

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双发射线圈感应电能传输系统的小信号建模及控制研究

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中国电机工程学报 2017年第20期37卷 6068-6076页

作者：麦瑞坤林天仁李勇何正友西南交通大学电气工程学院四川省成都市610031

双发射线圈的感应电能传输(inductive power transfer,IPT)系统能够实现有效分配两逆变器的输出功率,是提高电源侧输出容量的有效手段。该文分析了功率输出1:1工况下的双发射线圈的IPT系统的动态特性,旨在通过IPT系统的小信号模型求解... 详细信息

双发射线圈的感应电能传输(inductive power transfer,IPT)系统能够实现有效分配两逆变器的输出功率,是提高电源侧输出容量的有效手段。该文分析了功率输出1:1工况下的双发射线圈的IPT系统的动态特性,旨在通过IPT系统的小信号模型求解合适的数字PI控制器,提高负载电压动态响应特性,同时保证闭环系统具有充足的稳定裕度。首先,利用广义状态空间平均建模方法对IPT系统进行大信号模型及稳态工作点的分析。在此基础上,建立描述在IPT系统的输入受到扰动状态下的小信号模型。然后,借助Matlab中PIDtool工具箱设计合适的PI控制器参数,提高IPT系统负载电压响应性能,同时验证了闭环小信号模型具有充足的相角稳定裕度。最后,将闭环小信号模型分别与Simulink仿真模型、实验系统进行变电压动态响应对比,IPT系统的负载电压响应时间在13ms左右,与理论设计值相符,证明闭环小信号模型能准确描述系统动态响应。

关键词：双发射线圈感应电能传输广义状态空间平均小信号模型数字PI控制器

基于标准提取物的欧洲越橘提取物质量控制方法及药效活性关联研究

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中草药 2024年第8期55卷 2561-2570页

作者：李镇李俊安若凡孙伟岳中宝杨维贺瑞坤大理大学药学院云南大理671000 中国中医科学院中药研究所中药鉴定与安全性评估北京市重点实验室北京100007 汤臣倍健股份有限公司营养健康研究院广东广州510663

目的建立对照品非依赖性的20种花青素类成分定量分析方法,并利用该法对市售欧洲越橘Vaccinium myrtillus提取物进行质量控制,同时筛选出代表性抗氧化活性成分。方法以欧洲越橘标准对照提取物替代对照品,采用超高效液相色谱-三重四极杆... 详细信息

目的建立对照品非依赖性的20种花青素类成分定量分析方法,并利用该法对市售欧洲越橘Vaccinium myrtillus提取物进行质量控制,同时筛选出代表性抗氧化活性成分。方法以欧洲越橘标准对照提取物替代对照品,采用超高效液相色谱-三重四极杆串联质谱(UPLC-QQQ-MS/MS)联用技术,建立一种针对20种花青素类成分的定量方法,并利用该法对10批市售欧洲越橘提取物中的花青素类成分含量进行研究。采用DPPH自由基清除法和总抗氧化能力测试法评价不同欧洲越橘提取物的抗氧化能力。结果方法学验证结果显示,20种花青素类成分线性良好,r为0.9994~1.0000,精密度RSD为0.05%~4.23%,稳定性RSD为0.29%~3.38%,平均加样回收率为98.1%~102.1%,RSD为0.50%~4.12%。样品分析结果显示,不同样品中部分花青素类成分含量存在显著差异,其中锦葵素变化最大,RSD为18.23%。欧洲越橘提取物具有较好的DPPH自由基清除能力和总抗氧化能力。其中矢车菊素与DPPH自由基率相关性为0.94,芍药素-3-O-半乳糖苷与总抗氧化活性相关性为0.93。二者有望作为欧洲越橘提取物清除DPPH自由基活性和总抗氧化活性的潜在质控成分。结论基于UPLC-QQQ-MS/MS所建立的对照品非依赖性的欧洲越橘提取物中20种花青素类成分定量分析方法,灵敏度高,准确性好,方法简单,适用于欧洲越橘提取物中20种花青素类成分的含量测定,为中药对照提取物替代单体对照品在中药质量控制中的应用提供了数据支撑,为中药材质量控制研究提供新的研究思路。

关键词：欧洲越橘对照提取物 UPLC-QQQ-MS/MS 抗氧化能力质量控制花青素矢车菊素-3-O-葡萄糖苷芍药素-3-O-葡萄糖苷飞燕草素3-O-半乳糖苷锦葵素矢车菊素芍药素-3-O-半乳糖苷

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有限宽洋流产生的感应磁场数值分析

地球物理学进展 2024年第2期39卷 770-780页

作者：王瑞坤李腾飞刘健魏宝君石杰栋中国石油大学(华东)理学院青岛266580 中国船舶科学研究中心无锡214026

为了定量计算有限宽洋流产生的感应磁场,建立分层洋流物理模型,提出了有限宽洋流产生的感应磁场的计算方法.依托于分层洋流物理模型,计算矢势,得出有限宽洋流产生感应磁场的数值解.当洋流宽度趋于无穷大时,数值结果与无限宽洋流模型的... 详细信息

为了定量计算有限宽洋流产生的感应磁场,建立分层洋流物理模型,提出了有限宽洋流产生的感应磁场的计算方法.依托于分层洋流物理模型,计算矢势,得出有限宽洋流产生感应磁场的数值解.当洋流宽度趋于无穷大时,数值结果与无限宽洋流模型的解析结果一致,验证了方法的正确性.基于得到的数值表达式,分析海水宽度以及速度对感应磁场的影响规律.结果表明:对于常速洋流,宽度越大感应磁场在洋流中央的分布越稳定,在边缘处会减小,其次感应磁场在深度方向呈现线性分布的特点;对于水平速度衰减的洋流,洋流宽度以及速度的衰减程度对感应磁场的分布都有明显的影响,在合理的参数范围内,速度的衰减程度对感应磁场的影响更大;对于垂直速度衰减的洋流,感应磁场在深度方向存在一极大值,不同的洋流宽度以及速度衰减程度会对极值点的位置有明显的影响.

关键词：有限宽洋流感应磁场多层洋流模型洋流速度海洋电磁探测

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