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Cluster DetectionMethod of Endogenous Security Abnormal Attack Behavior in Air Traffic Control Network

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Computers, Materials & Continua 2024年第5期79卷 2523-2546页

作者： Ruchun Jia Jianwei zhang Yi Lin Yunxiang Han Feike Yang College of Computer Science Sichuan UniversityChengdu610065China Equipment Management and Unmanned Aerial Vehicle College of Air Force Engineering University Air Force Engineering UniversityXi’an710051China

In order to enhance the accuracy of Air Traffic Control(ATC)cybersecurity attack detection,in this paper,a new clustering detection method is designed for air traffic control network security *** feature set for ATC cybersecurity attacks is constructed by setting the feature states,adding recursive features,and determining the feature *** expected information gain and entropy of the feature data are computed to determine the information gain of the feature data and reduce the interference of similar feature *** autoencoder is introduced into the AI(artificial intelligence)algorithm to encode and decode the characteristics of ATC network security attack behavior to reduce the dimensionality of the ATC network security attack behavior *** on the above processing,an unsupervised learning algorithm for clustering detection of ATC network security attacks is ***,determine the distance between the clustering clusters of ATC network security attack behavior characteristics,calculate the clustering threshold,and construct the initial clustering ***,the new average value of all feature objects in each cluster is recalculated as the new cluster ***,it traverses all objects in a cluster of ATC network security attack behavior feature ***,the cluster detection of ATC network security attack behavior is completed by the computation of objective *** experiment took three groups of experimental attack behavior data sets as the test object,and took the detection rate,false detection rate and recall rate as the test indicators,and selected three similar methods for comparative *** experimental results show that the detection rate of this method is about 98%,the false positive rate is below 1%,and the recall rate is above 97%.Research shows that this method can improve the detection performance of security attacks in air traffic control network.

关键词： Air traffic control network security attack behavior cluster detection behavioral characteristics information gain cluster threshold automatic encoder

Safety analysis of temporary anchorage system for immersed tube in Shenzhen-Zhongshan Link

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第4期11卷 797-813页

作者： Lei Yan Jinning Yan Guoping Xu Shuanhai He Zechen zhang School of Highway Chang'an University Key Laboratory of Transport Industry of Bridge Detection Reinforcement Technology Chang'an University CCCC Highway Consultants Co.Ltd.

In the construction of the Shenzhen-Zhongshan Link, a temporary anchorage system,distributed uniformly along the pipe wall, has been employed. To assess the safety and reliability of this system, a combined method utilizing numerical analysis and model experiments was applied to study the safety of the temporary anchorage system and the reliability of the tension rods. Firstly, an overall model of the caisson segment based on GINA rebound force was established to analyze the stress state of the entire system. Secondly, a comprehensive numerical analysis and model experiment verification were conducted for the single tensioning system, revealing its failure mode and safety margin. The results indicate that the tension rod systems are uniformly stressed at an average of 444 k N during underwater jointing, with a safety factor of 1.94. At this point, the maximum von Mises stresses appearing at the front plate corners and the lower edge of the U-groove, with stress values of 181.8 MPa and 172.4 MPa, and safety factors of 1.54 and 1.71, *** the tension rod force reaches 940 k N, the tensioning system reaches its bearing limit,with initial yielding occurring at the front plate corners. Model experiments were conducted to verify the theoretical analysis results, under a test load of 444 k N, the stresses at the front plate corners and the lower edge of the U-groove were 159.6 and 195.9 MPa,respectively. As the test load increased to 940 k N, these stresses reached 390 and 389 MPa,exhibiting good agreement with the numerical analysis. Considering the uncertainty of loads and materials, a reliability analysis of the tension rods was conducted, yielding a reliability index of 4.34, meeting the secondary safety standard. Based on the comprehensive analysis, it can be concluded that the temporary anchorage system in the caisson segments of the Shenzhen-Zhongshan Link exhibits excellent safety margins.

关键词： Tunnel engineering Immersed tube structure Anchorage system Full-scale model test Load bearing performance Safety assessment.

Polycomb and trithorax:Their yin-yang dynamics in plants

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Molecular Plant 2024年第6期17卷 845-847页

作者： Fan Xu Daolei zhang Liang Le Li Pu Biotechnology Research Institute Chinese Academy of Agricultural SciencesBeijing 100081China School of Life Science Inner Mongolia UniversityHohhot 010021China

Polycomb(PcG)and trithorax(trxG)are two groups of conserved epigenetic complexes that maintain active and repressive states of target genes by altering their chromatin states to regulate plant development and stress *... 详细信息

关键词： maintain complexes states

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面向软件的随机数发生器设计和实现

计算机工程与设计 2024年第4期45卷 1004-1010页

作者：彭金辉张志鸿郑州信大捷安信息技术股份有限公司集成电路设计中心河南郑州450004 郑州大学计算机与人工智能学院河南郑州450001

为解决软件密码模块产品中随机数发生器的设计问题,特别是单一熵源的安全问题,提出一种通用的面向软件的随机数发生器方案。初始随机数采用系统熵池、本地随机数池和服务端采集的随机数3个熵源,其中系统熵池主要指当前操作系统下的环境... 详细信息

为解决软件密码模块产品中随机数发生器的设计问题,特别是单一熵源的安全问题,提出一种通用的面向软件的随机数发生器方案。初始随机数采用系统熵池、本地随机数池和服务端采集的随机数3个熵源,其中系统熵池主要指当前操作系统下的环境噪音,本地随机池指加密保存的一次性真随机数,服务端采集的随机数由硬件随机数发生器产生。产生初始随机数的同时,软件密码模块完成对用户的身份认证,建立客户端和服务端之间的安全通道。给出安全通道分析和随机数质量分析。方案实现依赖操作系统和网络通信,适用于移动智能终端、嵌入式终端等多种设备。

关键词：随机数软件密码模块随机数发生器软件随机数发生器物理噪声源操作系统熵池熵值

Non-bonding modulations between single atomic cerium and monodispersed selenium sites towards efficient oxygen reduction

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Nano Research 2024年第6期17卷 4753-4763页

作者： Leilei Yin Shuai zhang Mingzi Sun Siyuan Wang Bolong Huang Yaping Du Tianjin Key Lab for Rare Earth Materials and Applications Center for Rare Earth and Inorganic Functional MaterialsHaihe Laboratory of Sustainable Chemical TransformationsSmart Sensing Interdisciplinary Science CenterSchool of Materials Science and EngineeringNational Institute for Advanced MaterialsNankai UniversityTianjin 300350China Department of Applied Biology and Chemical Technology The Hong Kong Polytechnic UniversityHung HomKowloon 999077Hong KongChina Research Centre for Carbon-Strategic Catalysis The Hong Kong Polytechnic UniversityHung HomKowloon 999077Hong KongChina

Currently,dual atomic catalysts(DACs)with neighboring active sites for oxygen reduction reaction(ORR)still meet lots of challenges in the synthesis,especially the construction of atomic pairs of elements from different blocks of the periodic ***,a“rare earth(Ce)-metalloid(Se)”non-bonding heteronuclear diatomic electrocatalyst has been constructed for ORR by rational coordination and carbon support defect ***,the optimized Ce-Se diatomic catalysts(Ce-Se DAs/NC)displayed a half-wave potential of 0.886 V *** hydrogen electrode(RHE)and excellent stability,which surpass those of separate Ce or Se single atoms and most single/dual atomic catalysts ever *** addition,a primary zinc-air battery constructed using Ce-Se DAs/NC delivers a higher peak power density(209.2 mW·cm^(−2))and specific capacity(786.4 mAh·gZn^(−1))than state-of-the-art noble metal catalysts Pt/*** calculations reveal that the Ce-Se DAs/NC has improved the electroactivity of the Ce-N_(4)region due to the electron transfer towards the nearby Se specific activity(SA)***,the more electron-rich Se sites promote the adsorptions of key intermediates,which results in the optimal performances of ORR on Ce-Se DAs/*** work provides new perspectives on electronic structure modulations via non-bonded long-range coordination micro-environment engineering in DACs for efficient electrocatalysis.

关键词： catalyst rare earth oxygen reduction reaction(ORR) metalloid non-bonding modulation

Physiochemical and biological characteristics of fouling on landfill leachate treatment systems surface

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Journal of Environmental Sciences 2024年第1期135卷 59-71页

作者： Zhourui Gong Shu Yang Rui zhang Yangqing Wang Xiaoqing Wu Liyan Song School of resources and environmental engineering Anhui UniversityHefei 230601China Anhui Shengjin Lake Wetland Ecology National Long-term Scientific Research Base Dongzhi 247230China Key Laboratory of Three Gorges Reservoir Region’s Eco-Environment Ministry of EducationChongqing UniversityChongqing 400045China Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714China Xing Lu Huan Jing Co.LTD. Luzhou 646000China

Fouling of landfill leachate,a biofilm formation process on the surface of the collection system,migration pipeline and treatment system causes low efficiency of leachate transportation and treatment and increases cost for maintenance of those *** addition,landfill leachate fouling might accumulate pathogens and antibiotic resistance genes(ARGs),posing threats to the *** of the landfill leachate fouling and its associated environmental behavior is essential for the management of *** this study,physicochemical and biological properties of landfill leachate fouling and the possible accumulation capacity of pathogens and ARGs were investigated in nitrification(aerobic condition)and denitrification(anaerobic condition)process during landfill leachate biological treatment,*** show that microbial(bacterial,archaeal,eukaryotic,and viral)community structure and function(carbon fixation,methanogenesis,nitrification and denitrification)differed in fouling under aerobic and anaerobic conditions,driven by the supplemental leachate water *** fouling had a higher abundance of nitrification and denitrification functional genes,while anaerobic fouling harbored a higher abundance of carbon fixation and methanogenesis *** forms of leachate fouling had a higher abundance of pathogens and ARGs than the associated leachate,suggesting the accumulation capacity of fouling on biotic ***,aerobic fouling harbored three orders of magnitude higher multidrug resistance genes mex D than its associated *** finding provides fundamental knowledge on the biological properties of leachate fouling and suggests that leachate fouling might harbor significant pathogens and ARGs.

关键词： Landfill leachate fouling Biofilm Microbiome Carbon and nitrogen cycle Pathogens Antibiotic resistance genes

Estimating the optimal vegetation coverage for the dominant tree and shrub species over China's northwest drylands

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Science China Earth Sciences 2024年第5期67卷 1500-1517页

作者： Zhongdian zhang Xiaoxu JIA Ping ZHU Mingbin HUANG Lidong REN Ming’an SHAO School of Geographic Sciences Xinyang Normal UniversityXinyang 464000China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100190China Yellow River Delta Modern Agricultural Engineering Laboratory Chinese Academy of SciencesBeijing 100101China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYangling 712100China

Anthropogenic revegetation is an effective way to control soil erosion and restore degraded ecosystems in China's northwest drylands(NWD).However,excessive vegetation cover expansion has long been known to increase evapotranspiration,leading to reduced local water availability,which can in turn threaten the health and services of restored *** the optimal vegetation coverage(OVC)is critical for balancing the trade-off between plant growth and water consumption in water-stressed areas,yet quantitative assessments over the entire NWD are still *** this study,a modified Biome BioGeochemical Cycles(Biome-BGC)model was used to simulate the long-term(1961–2020)dynamics of actual evapotranspiration(ET_(a)),net primary productivity(NPP),and leaf area index(LAI)for the dominant non-native tree(*** and ***)and shrub(*** and ***)species at 246 meteorological sites over *** modified model incorporated the Richards equation to simulate transient unsaturated water flow in a multilayer soil module,and both soil and eco-physiological parameters required by the model were validated using field-observed ETadata for each *** distributions of OVC(given by the mean maximum LAI,LAI_(max))for the dominant species were determined within three hydrogeomorphic sub-areas(i.e.,the loess hilly-gully sub-area,the windy and sandy sub-area,and the desert sub-area).The modified Biome-BGC model performed well in terms of simulating ET_(a) dynamics for the four plant *** distributions of mean ET_a,NPP,and LAI_(max)generally exhibited patterns similar to mean annual precipitation(MAP).In the loess hilly-gully sub-area(MAP:210 to 710 mm),the OVC respectively ranged from 1.7 to 2.9 and 0.8 to 2.9 for *** and *** the windy and sandy sub-area(MAP:135 to 500 mm),the OVC ranged from 0.3 to 3.3,0.5 to 2.6 and 0.6 to 2.1for ***,*** and ***,*** the desert sub-

关键词： Optimal vegetation coverage Water balance Leaf area index Biome-BGC model Dryland

Recent advancement of sonogenetics:A promising noninvasive cellular manipulation by ultrasound

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Genes & Diseases 2024年第5期11卷 163-182页

作者： Jin Tang Mingxuan Feng Dong Wang Liang zhang Ke Yang Pediatric Research Institute Children’s Hospital of Chongqing Medical UniversityNational Clinical Research Center for Child Health and DisordersMinistry of Education Key Laboratory of Child Development and DisordersChina International Science and Technology Cooperation Base of Child Development and Critical DisordersChongqing Engineering Research Center of Stem Cell TherapyChongqing 400014China Department of Ultrasound The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Tongji Medical College Huazhong University of Science and TechnologyWuhanHubei 430074China

Recent advancements in biomedical research have underscored the importance of noninvasive cellular manipulation ***,a method that uses genetic engineering to produce ultrasound-sensitive proteins in target cells,is gaining prominence along with optogenetics,electrogenetics,and *** stimulation with ultrasound,these proteins trigger a cascade of cellular activities and *** traditional ultrasound modalities,sonogenetics offers enhanced spatial selectivity,improving precision and safety in disease *** technology broadens the scope of non-surgical interventions across a wide range of clinical research and therapeutic applications,including neuromodulation,oncologic treatments,stem cell therapy,and *** current literature predominantly emphasizes ultrasonic neuromodulation,this review offers a comprehensive exploration of *** discuss ultrasound properties,the specific ultrasound-sensitive proteins employed in sonogenetics,and the technique’s potential in managing conditions such as neurological disorders,cancer,and ophthalmic diseases,and in stem cell *** objective is to stimulate fresh perspectives for further research in this promising field.

关键词： Mechanosensitive channel Neuromodulation Sonogenetics Ultrasound Ultrasound-sensitive protein

Er^(3+)/Nd^(3+)/Tm^(3+)共掺碲酸盐玻璃近红外发射和能量传递机理

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光谱学与光谱分析 2024年第4期44卷 1171-1176页

作者：陈安民马飞云崔令江张鹏王传杰威海长和光导科技有限公司威海市光纤预制棒工程技术研究中心山东威海264200 哈尔滨工业大学(威海)材料科学与工程学院山东威海264209 宏安集团有限公司技术部山东威海264200

为满足通信网络飞速发展对密集波分复用系统(DWDM)传输容量需求的不断增加,对DWDM系统核心器件掺铒光纤放大器(EDFA)性能的要求也越来越高。碲酸盐玻璃因其具有稀土离子溶解度高,声子能量低和高折射率等优点已成为替代传统掺铒石英光纤... 详细信息

为满足通信网络飞速发展对密集波分复用系统(DWDM)传输容量需求的不断增加,对DWDM系统核心器件掺铒光纤放大器(EDFA)性能的要求也越来越高。碲酸盐玻璃因其具有稀土离子溶解度高,声子能量低和高折射率等优点已成为替代传统掺铒石英光纤的理想材料。掺稀土碲酸盐玻璃可以作为宽带光纤放大器的理想增益介质来实现信号有效放大,因此提高掺铒碲酸盐玻璃光谱性能并拓展其放大带宽对DWDM系统扩容具有重要意义。通过Er^(3+)、Nd^(3+)和Tm^(3+)共同掺杂提高碲酸盐玻璃的放大带宽以获得超宽带发光。Er^(3+)、Nd^(3+)和Tm^(3+)分别通过跃迁产生1.55、1.34和1.85μm波段的发光,且三个近红外发射波段基本相邻。采用三种离子共掺的方式,通过离子间发生能量传递(ET)来实现碲酸盐玻璃在连续光谱中的发光。在TeO_(2)-WO_(3)-ZnO-Na_(2)O-Er_(2)O_(3)碲酸盐玻璃中,先进行Er^(3+)/Nd^(3+)掺杂,分析Er^(3+)/Nd^(3+)间能量传递机理,得到Er_(2)O_(3)、Nd_(2)O_(3)掺杂浓度分别为1、0.1 mol%时玻璃发光强度较佳。再进行不同Tm^(3+)浓度下的Er^(3+)/Nd^(3+)/Tm^(3+)三种离子掺杂,最后采用高温熔融退火法制备得到热稳定性能良好的Er^(3+)/Nd^(3+)/Tm^(3+)掺杂碲酸盐玻璃。Er^(3+)、Nd^(3+)和Tm^(3+)间发生能量传递,在1250~2100 nm范围内产生了发光中心为1.3、1.5和1.8μm的三个波段发光,覆盖了整个O、E、S、C、L和U波段。1.5μm处的荧光半高宽(FWHM)增加到131.68 nm,1.8μm处的FWHM高达251.75 nm。详细分析了三种稀土掺杂时稀土离子之间的能量传递过程机理。光谱结果表明,当Er_(2)O_(3)、Nd_(2)O_(3)、Tm_(2)O_(3)掺杂浓度分别为1、0.1、0.2 mol%时,Er^(3+)/Nd^(3+)/Tm^(3+)三掺碲酸盐玻璃是超宽带光纤放大器设计的一种有效材料。

关键词：碲酸盐玻璃近红外发光能量传递热稳定性能