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Functional Pattern-Related Anomaly Detection Approach Collaborating Binary Segmentation with Finite State Machine

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Computers, Materials & Continua 2023年第12期77卷 3573-3592页

作者： Ming wan Minglei Hao jiawei Li Jiangyuan Yao Yan Song School of Information Liaoning UniversityShenyang110036China School of Computer Science and Technology Hainan UniversityHaikou570228China School of Physics Liaoning UniversityShenyang110036China

The process control-oriented threat,which can exploit OT(Operational Technology)vulnerabilities to forcibly insert abnormal control commands or status information,has become one of the most devastating cyber attacks in industrial automation *** effectively detect this threat,this paper proposes one functional pattern-related anomaly detection approach,which skillfully collaborates the BinSeg(Binary Segmentation)algorithm with FSM(Finite State Machine)to identify anomalies between measuring data and control *** detecting the change points of measuring data,the BinSeg algorithm is introduced to generate some initial sequence segments,which can be further classified and merged into different functional patterns due to their backward difference means and *** analyzing the pattern association according to the Bayesian network,one functional state transition model based on FSM,which accurately describes the whole control and monitoring process,is constructed as one feasible detection ***,we use the typical SWaT(Secure Water Treatment)dataset to evaluate the proposed approach,and the experimental results show that:for one thing,compared with other change-point detection approaches,the BinSeg algorithm can be more suitable for the optimal sequence segmentation of measuring data due to its highest detection accuracy and least consuming time;for another,the proposed approach exhibits relatively excellent detection ability,because the average detection precision,recall rate and F1-score to identify 10 different attacks can reach 0.872,0.982 and 0.896,respectively.

关键词： Process control-oriented threat anomaly detection binary segmentation FSM

Methoxylation and Direct Hydrogenative Coupling of Chloronitrobenzenes in Continuous Flow

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Chinese Journal of Chemistry 2017年第4期35卷 410-414页

作者： Songjie Shi Li wan Xiaoning Sun jiawei Zhang Kai Guo College of Biotechnology and Pharmaceutical Engineering Nanjing Tech University Nanjing Jiangsu 211816 China State Key Laboratory of Materials-Oriented Chemical Engineering Nanjing Tech University Nanjing Jiangsu 210009 China Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM) 30 Puzhu South Road Nanjing Jiangsu 211816 China

A novel continuous flow method for the methoxylation of chloronitrobenzenes was developed. The reaction went smoothly and high yields were achieved under the optimized conditions. Furthermore, up to 76% yield of azoxybenzenes were obtained from the corresponding nitrobenzenes in the presence of NaOH in continuous flow. Compared to batch conditions, the reaction time was significantly shortened, and the chemical waste was reduced obviously.

关键词： methoxylation azoxybenzenes chloronitrobenzenes continuous flow sodium methoxide

基于序贯设计和高斯过程模型的结构动力不确定性量化方法

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浙江大学学报（工学版） 2024年第3期58卷 529-536页

作者：万华平张梓楠周家伟任伟新浙江大学建筑工程学院浙江杭州310058 浙江大学平衡建筑研究中心浙江杭州310028 浙江大学建筑设计研究院有限公司浙江杭州310028 深圳大学土木与交通工程学院广东深圳518060

将直接基于有限元模型的蒙特卡罗方法用于结构动力不确定性量化较耗时,为此采用高斯过程模型取代耗时的有限元模型,提高不确定性量化的计算效率.提出基于序贯设计和高斯过程模型的结构动力不确定性量化方法,通过样本填充准则迭代,选择... 详细信息

将直接基于有限元模型的蒙特卡罗方法用于结构动力不确定性量化较耗时,为此采用高斯过程模型取代耗时的有限元模型,提高不确定性量化的计算效率.提出基于序贯设计和高斯过程模型的结构动力不确定性量化方法,通过样本填充准则迭代,选择最优样本点建立自适应高斯过程模型,提升动力不确定性量化精度.在建立的自适应高斯过程模型框架下,动力特性统计矩的高维积分转化为一维积分,进而进行解析计算.采用2个数学函数来展示自适应高斯模型的拟合过程,高斯过程模型的拟合精度随着迭代次数增加而明显增加.将所提方法应用于柱面网壳的固有频率统计矩计算,计算精度与蒙特卡罗法的结果相当.与传统高斯过程模型对比,所提算法的计算效率优势明显,表明所提方法具有计算精度高和效率高的优势.

关键词：结构动力特性不确定性量化序贯设计高斯过程模型统计矩

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河北省顺平县地质灾害发育特征及易发性评价

地质力学学报 2020年第4期26卷 604-614页

作者：万佳威丰成君戚帮申孙明乾杨肖肖王惠卿范玉璐张鹏孟静谭成轩中国地质科学院地质力学研究所北京100081 新构造运动与地质灾害重点实验室北京100081 中国地质大学(北京) 北京100083 北京市地质勘察技术院北京100120

河北省顺平县位于太行山东麓,主要发育有崩塌、滑坡、泥石流、地裂缝等四种类型地质灾害。基于该县地质灾害发育特征,采用GIS技术和信息量数学评价模型,选取坡度、起伏度、坡向、工程地质岩组、归一化植被指数(NDVI)、与河流的距离6个... 详细信息

河北省顺平县位于太行山东麓,主要发育有崩塌、滑坡、泥石流、地裂缝等四种类型地质灾害。基于该县地质灾害发育特征,采用GIS技术和信息量数学评价模型,选取坡度、起伏度、坡向、工程地质岩组、归一化植被指数(NDVI)、与河流的距离6个评价因子,对顺平县地质灾害进行易发性评价。评价结果显示:高易发区面积约为125 km^2,占全县总面积的17.5%,分散分布于西北部的中低山和丘陵地区,密集发育崩塌灾害,少量发育滑坡、泥石流灾害;中易发区面积约为200 km^2,占全县总面积的28.0%,成片分布于西北部的中低山和丘陵地区,少量发育崩塌、滑坡、泥石流灾害;低易发区面积约为389 km^2,占全县总面积的54.5%,主要分布于东南部的平原地区及西北部丘陵地区内的宽阔沟谷,沿古河道发育地裂缝灾害,个别地区发育崩塌、滑坡灾害。

关键词：太行山东麓地质灾害发育特征易发性信息量模型

A local Martian crustal field model: Targeting the candidate landing site of the 2020 Chinese Mars Rover

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Earth and Planetary Physics 2020年第4期4卷 420-428页

作者： XinZhou Li ZhaoJin Rong jiawei Gao Yong Wei Zhen Shi Tao Yu WeiXing wan Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth Science University of Chinese Academy of SciencesBeijing 100049China Beijing National Observatory of Space Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China China University of Geosciences Wuhan 430074China

Unlike Earth,Mars lacks a global dipolar magnetic field but is dominated by patches of a remnant crustal magnetic *** 2021,the Chinese Mars Rover will land on the surface of Mars and measure the surface magnetic field along a moving path within the possible landing region of 20°W-50°W,20°N-30°*** scientific target of the Rover is to monitor the variation in surface remnant magnetic fields and reveal the source of the ionospheric *** accurate local crustal field model is thus considered necessary as a field *** we establish a local crust field model for the candidate landing site based on the joint magnetic field data set from Mars Global Explorer(MGS)and Mars Atmosphere and Volatile Evolution(MAVEN)data *** model is composed of 1,296 dipoles,which are set on three layers but at different buried *** application of the dipole model to the joint data set allowed us to calculate the optimal parameters of their *** calculated results demonstrate that our model has less fitting error than two other state-of-the art global crustal field models,which would indicate a more reasonable assessment of the surface crustal field from our model.

关键词： Mars remnant crustal field crustal field model dipole sources Chinese Mars mission

Solution-phase synthesis of ordered mesoporous carbon as resonant-gravimetric sensing material for room-temperature H2S detection

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Chinese Chemical Letters 2020年第6期31卷 1680-1685页

作者： jiawei Ni Tao Zhao Lei Tang Pengpeng Qiu wan Jiang Lianjun wang Pengcheng Xu Wei Luo State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringInstitute of Functional MaterialsDonghua UniversityShanghai 201620China State Key Laboratory of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China College of Life and Environmental Sciences Shanghai Normal UniversityShanghai 200234China University of Chinese Academy of Sciences Beijing 100049China

H2S can cause multiple diseases and poses a great threat to human ***,the precise detection of extremely toxic H2S at room temperature is still a great ***,a facile solvent evaporation induced aggregating assembly(EIAA)method has been applied for the production of ordered mesoporous carbon(OMCs)in an acidic THF/H2 O solution with high-molecular-weight poly(ethylene oxide)-b-polystyrene(PEO-b-PS)copolymers as the structure-directing agent,formaldehyde and resorcinol as carbon *** with the continuous evaporation of THF from the mixed solution,cylindrical micelles are formed in the solution and further assemble into highly ordered *** obtained OMCs possesses a two-dimensional(2 D)hexagonal mesostructure with uniform and large pore diameter(~19.2 nm),high surface area(599 m2/g),and large pore volume(0.92 cm3/g).When being used as the resonant cantilever gas sensor for room-temperature H2S detection,the OMCs has delivered not only a superior gas sensing performance with ultrafast re s ponse(14 s)and recovery(21 s)even at low concentration(2 ppm)but also an excellent selectivity toward H2S among various common interfering ***,the limit of detection is better than 0.2 ppm,indicating its potential application in environmental monitoring and health protection.

关键词： Mesoporous materials Carbon Self-assembly Resonant cantilever gas sensor H2S

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河北省顺平县李思庄滑坡稳定性分析

地质力学学报 2020年第4期26卷 595-603页

作者：王惠卿丰成君戚帮申王继明孙明乾杨肖肖万佳威范玉璐张鹏孟静谭成轩中国地质科学院地质力学研究所北京100081 新构造运动与地质灾害重点实验室北京100081 北京市地质勘察技术院北京100120 中国联合工程有限公司浙江杭州310051 中国地质大学(北京) 北京100083

李思庄滑坡为河北省顺平县境内潜在危险性最大的一残坡积堆积层滑坡,近年由于削坡建房,滑坡稳定性降低,极端降雨条件下存在复活可能。在野外调查确定滑坡结构特征的基础上,采用改进Mein-Larson降雨入渗模型分析不同降雨强度及持时对李... 详细信息

李思庄滑坡为河北省顺平县境内潜在危险性最大的一残坡积堆积层滑坡,近年由于削坡建房,滑坡稳定性降低,极端降雨条件下存在复活可能。在野外调查确定滑坡结构特征的基础上,采用改进Mein-Larson降雨入渗模型分析不同降雨强度及持时对李思庄滑坡安全系数影响,运用有限差分软件FLAC3D计算分析该滑坡在天然和极端降雨工况下的稳定状态。研究结果表明:天然状态下,边坡潜在滑移面为基岩与残坡积层分界面,边坡安全系数为1.18,未发生失稳破坏;随降雨历时增加,潜在滑移面由基岩与残坡积层分界面转移到湿润峰面,当湿润峰达到基岩与残坡积层分界面,边坡安全系数为0.83,属不稳定状态。并对李思庄滑坡初步提出设置挡土墙和截排水沟的治理建议。

关键词：堆积层滑坡稳定性 Mein-Larson降雨入渗模型 FLAC3D

Synthesis of SiO_2@SiO_2 core-shell microspheres using urea-formaldehyde polymers as the templates for fast separation of small solutes and proteins

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Chinese Chemical Letters 2018年第1期29卷 213-216页

作者： Guangping wan Hongjun Xia Jun wang jiawei Liu Botao Song Ying Yang Quan Bai Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education Institute of Modem Separation Science Key Lab of Modern Separation Science in Shaanxi Province Northwest University Shaanxi Research Design Institute of Petroleum and Chemical Industry Shaanxi Dangerous Chemical Supervision and Inspection Center

Superficially porous core-shell silica microspheres （CSSMs） have been a great success for the fast separation of small molecules and proteins in recent years. In this paper, the CSSMs were synthesized by an improved polymerization-induced colloid aggregation （PICA） method using urea-formaldehyde polymers as the templates. The agglomeration of the functionalized silica core was avoided by the surface modification through reflux with ureidopropyltrimethoxysilane in the neutral ethanol solution at 80 ~C, and the secondary nucleation of the silica nanoparticles during the preparation process could also be inhibited via the optimization of the reaction conditions, such as pH, temperature, colloidal silica sol concentration and the reaction time. The controllable shell thickness and pore size of the synthesized monodisperse CSSMs were successfully obtained by adjusting the weight ratio of silica core/colloidal silica sol and the particle size of colloidal silica sol, respectively. The C18-modified CSSMs with different pore sizes were used to separate small solutes and proteins. The higher efficient separation and relatively low back pressure of the synthesized core-shefi column demonstrate that the CSSMs have a great ootential aoolication for fast HPLC

关键词： Core-shell silica microspherePolymerization-induced colloid aggregationUrea-formaldehyde polymersFast separationHPLC

Cu/AC臭氧催化氧化深度处理复糟酱香型白酒废水

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中国酿造 2024年第9期43卷 140-146页

作者：李博文梁家伟代吉华万东锦李圣斐买文宁张坡郑州大学生态与环境学院河南郑州450001 河南工业大学环境工程学院郑州市水安全与水生态技术重点实验室河南郑州450001 河南君和环保科技有限公司河南省生态环保型污水净化工程技术研究中心河南郑州450001 中建中原建筑设计院有限公司河南郑州450003

该实验考察了活性炭负载铜氧化物(Cu/AC)为催化剂的微气泡臭氧催化氧化工艺对复糟酱香型白酒废水生化出水的深度处理效果。结果表明,序批式反应中催化剂投加量为15 g/L,臭氧投加量为12.5 mg/min,初始pH为7.5时,在此条件下,化学需氧量(C... 详细信息

该实验考察了活性炭负载铜氧化物(Cu/AC)为催化剂的微气泡臭氧催化氧化工艺对复糟酱香型白酒废水生化出水的深度处理效果。结果表明,序批式反应中催化剂投加量为15 g/L,臭氧投加量为12.5 mg/min,初始pH为7.5时,在此条件下,化学需氧量(COD)和波长254nm处紫外吸光值(UV_(254))去除率分别为79.0%和94.7%。催化剂多次使用后COD和UV_(254)去除率下降幅度均<5%。表征结果显示,催化剂表面形态平整,铜元素主要以CuO的形式存在并分散在AC上,有利于提升催化性能。经过长时间连续运行,COD和UV_(254)去除率仍能达到76%和92%,有较强稳定性和抗冲击能力。研究结果为微气泡臭氧催化氧化体系在复糟酱香白酒废水处理领域应用提供参考。

关键词：复糟酱香白酒废水微气泡臭氧非均相催化剂催化剂表征