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实时混合对抗蠕虫的建模和分析

湖南大学学报（自然科学版） 2011年第5期38卷 74-78页

作者：秦拯李军群欧露 alex x.liu 湖南大学软件学院湖南长沙410082 密歇根州立大学计算机科学与工程系密歇根兰西488241266

传统的防病毒技术难以抵御蠕虫的传播,为此本文提出实时混合对抗技术,该技术在被对抗蠕虫感染的主机与易感染主机数量相等时转换对抗策略,并建立实时混合对抗蠕虫的传播模型.最后,通过仿真实验从对抗有效性、资源消耗和应对突发事件能... 详细信息

传统的防病毒技术难以抵御蠕虫的传播,为此本文提出实时混合对抗技术,该技术在被对抗蠕虫感染的主机与易感染主机数量相等时转换对抗策略,并建立实时混合对抗蠕虫的传播模型.最后,通过仿真实验从对抗有效性、资源消耗和应对突发事件能力三个方面验证实时混合对抗技术的性能.理论分析和实验结果表明,实时混合对抗技术能更好地满足对抗有效性和低资源消耗要求,并能应对突发事件.

关键词：网络安全网络蠕虫对抗蠕虫传播模型实时混合对抗技术

一种基于SFDD的状态防火墙规则集比对方法

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湖南大学学报（自然科学版） 2014年第10期41卷 103-107页

作者：秦拯厉怡君欧露 alex x.liu 湖南大学信息科学与工程学院湖南长沙410082 密歇根州立大学计算机科学与工程系密歇根兰西488241266

状态防火墙是一种新型防火墙,而传统防火墙决策图(FDD)构造算法并不适用于状态防火墙的规则集比对.本文在FDD基础上,提出一种状态防火墙决策图(SFDD)构造算法,将规则集转化成图形化的等价的SFDD,用于状态防火墙规则集比对.理论分析和仿... 详细信息

状态防火墙是一种新型防火墙,而传统防火墙决策图(FDD)构造算法并不适用于状态防火墙的规则集比对.本文在FDD基础上,提出一种状态防火墙决策图(SFDD)构造算法,将规则集转化成图形化的等价的SFDD,用于状态防火墙规则集比对.理论分析和仿真实验结果表明,利用SFDD构造算法进行比对,能有效检测出规则集之间的全部不同点;当状态防火墙的状态部分规则和无状态部分规则条目数量均达到3 000时,比对过程所耗费的平均时间不超过2s.

关键词：网络安全防火墙规则访问控制

Amorphous Iridium Oxide-Integrated Anode Electrodes with Ultrahigh Material Utilization for Hydrogen Production at Industrial Current Densities

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Nano-Micro Letters 2024年第10期16卷 225-239页

作者： Lei Ding Kui Li Weitian Wang Zhiqiang xie Shule Yu Haoran Yu David ACullen alex Keane Kathy Ayers Christopher BCapuano Fangyuan liu Pu-xian Gao Feng-Yuan Zhang Department of Mechanical Aerospace and Biomedical EngineeringUniversity of TennesseeKnoxvilleTN 37996USA Oak Ridge National Lab Center for Nanophase Materials SciencesOak RidgeTN 37831USA Nel Hydrogen WallingfordCT 06492USA Institute of Materials Science University of ConnecticutStorrsCT 06269USA Department of Materials Science and Engineering University of ConnecticutStorrsCT 06269USA

Herein,ionomer-free amorphous iridium oxide(IrO_(x))thin electrodes are first developed as highly active anodes for proton exchange membrane electrolyzer cells(PEMECs)via low-cost,environmentally friendly,and easily scalable electrodeposition at room *** with a Nafion 117 membrane,the IrO_(x)-integrated electrode with an ultralow loading of 0.075 mg cm^(-2)delivers a high cell efficiency of about 90%,achieving more than 96%catalyst savings and 42-fold higher catalyst utilization compared to commercial catalyst-coated membrane(2 mg cm^(-2)).Additionally,the IrO_(x)electrode demonstrates superior performance,higher catalyst utilization and significantly simplified fabrication with easy scalability compared with the most previously reported ***,the remarkable performance could be mainly due to the amorphous phase property,sufficient Ir^(3+)content,and rich surface hydroxide groups in ***,due to the high activity,high cell efficiency,an economical,greatly simplified and easily scalable fabrication process,and ultrahigh material utilization,the IrO_(x)electrode shows great potential to be applied in industry and accelerates the commercialization of PEMECs and renewable energy evolution.

关键词： Ionomer-free Amorphous IrOx electrodes Ultrahigh material utilization Scalable electrodeposition Hydrogen production

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桃花心木木材定量解剖特征变异性及其识别

林业科学 2024年第5期60卷 169-176页

作者：刘守佳何拓陆杨焦立超郭娟 alex CWiedenhoeft 殷亚方中国林业科学研究院木材工业研究所北京100091 中国林业科学研究院木材标本馆北京100091 国家林业和草原局木材标本资源库北京100091 国家林业和草原局野生动物保护监测中心北京100714 美国林产品实验室木材解剖研究中心麦迪逊WI 53706

[目的]基于定量解剖方法探究桃花心木属3种树种木材的构造特征,揭示其不同构造特征的种间和种内变异规律,为木材“种”水平的准确识别提供科学依据。[方法]针对大叶桃花心木、桃花心木和矮叶桃花心木木材标本显微切片,通过光学显微镜采... 详细信息

[目的]基于定量解剖方法探究桃花心木属3种树种木材的构造特征,揭示其不同构造特征的种间和种内变异规律,为木材“种”水平的准确识别提供科学依据。[方法]针对大叶桃花心木、桃花心木和矮叶桃花心木木材标本显微切片,通过光学显微镜采集其横、径、弦三切面微观构造图像,利用图像分析软件分别测量导管分子长度、管孔弦向直径、管孔频率、木纤维长度、木射线宽度、木射线高度和木射线频率7个定量解剖特征,分析其不同构造特征的种间和种内变异规律;采用随机森林算法对木材树种进行识别,比较木材不同定量解剖特征对识别准确率的贡献度。[结果]3种桃花心木木材显微切片图像中管孔、轴向薄壁组织和木射线等构造特征相似,通过人工方式难以区分;除木射线宽度外,其他6组定量解剖特征在种间均存在显著差异;随机森林算法对桃花心木的识别准确率达86.67%,7个定量解剖特征对木材识别结果的贡献度存在差异,其中导管分子长度的平均准确率降低度值(3.956)和平均基尼指数降低度值(6.311)最大,管孔弦向直径次之,木射线宽度的平均准确率降低度值(0.797)和平均基尼指数降低度值(2.175)最小,表明导管分子长度的贡献度最大,木射线宽度的贡献度最小。[结论]采用木材定量解剖方法,揭示3种桃花心木构造特征的种间和种内变异规律以及在木材识别中起关键作用的定量解剖特征,可为实现木材“种”水平的准确识别提供科学依据。

关键词：桃花心木定量解剖变异规律随机森林木材识别

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Rational design of efficient visible-light photocatalysts(1D@2D/0D)ZnO@Ni-doped BiOBr/Bi heterojunction:Considerations on hierarchical structures,doping and SPR effect

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Journal of Materials Science & Technology 2022年第30期125卷 38-50页

作者： Zhouzheng Jin Jingru Li Yiming Zhang Dan liu Hui Ding Bhekie B.Mamba alex T.Kuvarega Jianzhou Gui State Key Laboratory of Separation Membranes and Membrane Processes Tianjin Key Laboratory of Green Chemical Technology and Process Engineeringand School of Material Science and EngineeringTiangong UniversityTianjin 300387China School of Chemical Engineering and Technology Tiangong UniversityTianjin 300387China School of Chemistry Tiangong UniversityTianjin 300387China School of Environmental Science and Engineering Tianjin UniversityTianjin300072China University of South Africa College of ScienceEngineering and TechnologyNanotechnology and Water Sustainability Research UnitFlorida Science Campus 1710South Africa

Simultaneously integrating heterogeneous interface,element doping,and metal decorating was a promising strategy to promote the visible-light-driven photocatalytic ***,we demonstrated a facile solvothermal route for Ni-doped BiOBr/Bi^(0) with ZnO 3D hierarchical heterojunction(denoted as Z@B/BiNi).The optimal photocatalysts of Z@B/Bi-Ni sample presented a remarkable catalytic performance of high concentrations of tetracycline solution(40 mg/L)than those of the Z@B/Bi,Z@B,BOB and ZnO photocatalysts toward the visible-light-driven *** enhanced photocatalytic mechanism can be proposed as follows:(ⅰ)3D hierarchical heterojunction provided more active sites and accelerated the separation of charge carriers for photocatalytic TC;(ⅱ)formation of oxygen vacancies on the surface over Z@B/Bi-Ni by in-situ reduction of Bi^(0) and Ni doping could serve as the active sites for oxygen activation to adsorb free O_(2) and generate more superoxide radicals;(ⅲ)SPR effect of Bi metal were beneficial to carrier separation and also act as the active site to trap O_(2) *** work clarified the role of unique morphologies,surface plasmonic resonance(SPR)effect of metal Bi,and Ni doping in Z@B/Bi-Ni,and its photocatalytic reaction mechanism was proposed by a series of experiments,characterization and DFT calculations,arousing a new perspective to design hierarchical heterojunction photocatalysts.

关键词： Hierarchical heterojunction Oxygen vacancies Doping Ni SPR effect Photocatalysis

Levels of rhizome endophytic fungi fluctuate in Paris polyphylla *** as plants age

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Plant Diversity 2017年第1期39卷 60-64页

作者： Tao liu alex Greenslade ShengchaoYang Yunnan Research Center on Good Agricultural Practice for Dominant Chinese Medicinal Materials Yunnan Agricultural University Kunming 650201China Biological Chemistry and Crop Protection Rothamsted Research Harpenden UK

Paris polyphylla var. yunnanensis is an important medicinal plant with abundant saponins that are widely used in the pharmaceuticals industry. It is unclear why the levels of active ingredients increase as these plants age. We speculated that the concentrations of those components in the rhizomes are mediated by fungal endophytes. To test this hypothesis, we took both culture-dependent and-independent(metagenomics) approaches to analyze the communities of endophytic fungi that inhabit those rhizomes in plants of different age classes(four, six, and eight years old). In all, 147 isolates representing 18 fungal taxa were obtained from 270 segments(90 per age class). Based on morphological and genetic characteristics, Fusarium oxysporum(46.55% frequency of occurrence) was the predominant endophyte,followed by Leptodontidium sp.(8.66%) and Trichoderma viride(6.81%). Colonization of endophytic fungi was maximized in the eight-year-old rhizomes(33.33%) when compared with four-year-old(21.21%) and six-year-old(15.15%) rhizomes. Certain fungal species were present only at particular ages. For example,Alternaria sp., Cylindrocarpon sp., Chaetomium sp., Paraphaeosphaeria sporulosa, Pyrenochaeta sp., Penicillium swiecickii, T. viride, and Truncatella angustata were found only in the oldest plants. Analysis of(metagenomics) community DNA extracted from different-aged samples revealed that, at the class level,the majority of fungi had the highest sequence similarity to members of Sordariomycetes, followed by Eurotiomycetes and Saccharomycetes. These results were mostly in accord with those we obtained using culture methods. Fungal diversity and richness also changed over time. Our investigation is the first to show that the diversity of fungi in rhizomes of P. polyphylla var. yunnanensis is altered as plants age, and our findings provide a foundation for future examinations of useful compounds.

关键词： Medicinal plants Endophytic fungi Paris polyphylla var.yunnanensis

Database Commons:A Catalog of Worldwide Biological Databases

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Genomics, Proteomics & Bioinformatics 2023年第5期21卷 1054-1058页

作者： Lina Ma Dong Zou Lin liu Huma Shireen Amir AAbbasi alex Bateman Jingfa xiao Wenming Zhao Yiming Bao Zhang Zhang National Genomics Data Center Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijing 100101China CAS Key Laboratory of Genome Sciences and Information Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China National Center for Bioinformatics Programme of Comparative and Evolutionary GenomicsFaculty of Biological SciencesQuaid-i-Azam UniversityIslamabad 45320Pakistan European Molecular Biology Laboratory European Bioinformatics Institute(EMBL-EBI)HinxtonCambridge CB101SDUnited Kingdom

Biological databases serve as a global fundamental infrastructure for the worldwide scientific community,which dramatically aid the transformation of big data into knowledge discovery and drive significant innovations in a wide range of research *** the rapid data production,biological databases continue to increase in size and *** build a catalog of worldwide biological databases,we curate a total of 5825 biological databases from 8931 publications,which are geographically distributed in 72 countries/regions and developed by 1975 institutions(as of September 20,2022).We further devise a z-index,a novel index to characterize the scientific impact of a database,and rank all these biological databases as well as their hosting institutions and countries in terms of citation and ***,we present a series of statistics and trends of worldwide biological databases,yielding a global perspective to better understand their status and impact for life and health *** up-to-date catalog of worldwide biological databases,as well as their curated meta-information and derived statistics,is publicly available at Database Commons(https://***/databasecommons/).

关键词： Biological database Catalog Database Commons Citation z-index

Broadband photomultiplication-type polymer photodetectors and its application in light-controlled circuit

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Science China Chemistry 2022年第8期65卷 1642-1649页

作者： Ming liu Qunping Fan Kaixuan Yang Zijin Zhao xingchao Zhao Zhengji Zhou Jian Zhang Francis Lin alex K.-Y.Jen Fujun Zhang Key Laboratory of Luminescence and Optical Information Ministry of EducationBeijing Jiaotong UniversityBeijing 100044China Department of Chemistry City University of Hong KongHong Kong 999077China State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China Key Lab for Special Functional Materials Ministry of EducationNational and Local Joint Engineering Research Center for High-Efficiency Display and Lighting Technologyand School of MaterialsHenan UniversityKaifeng 475004China Guangxi Key Laboratory of Information Materials School of Material Science and TechnologyGuilin University of Electronic TechnologyGuilin 541004China Department of Materials Science and Engineering City University of Hong KongHong Kong 999077China Department of Materials Science and Engineering University of WashingtonWashington 98195-2120United States Hong Kong Institute for Clean Energy City University of Hong KongHong Kong 999077China

Photomultiplication-type polymer photodetectors(PM-PPDs)were achieved with polymer P3HT as donor and PY3Se-1V as acceptor based on structure of ITO/PEDOT:PSS/active layer/*** optimal weight ratio of P3HT to PY3Se-1V is about 100:*** of isolated electron traps are formed with PY3Se-1V surrounded by P3HT due to rather less content of PY3Se-1V in active layers and about 0.94 e V energy offset between the lowest unoccupied molecular orbitals(LUMO)of P3HT and *** optimal PM-PPDs exhibit broad spectral response from 350 to 950 nm and external quantum efficiency(EQE)values of68,200%at 360 nm,26,400%at 630 nm and 19,500%at 850 nm under-15 V *** working mechanism of PM-PPDs is attributed to the interfacial trap-assisted hole tunneling injection from external *** performance of PM-PPDs can be further improved by incorporating appropriate PMBBDT with high hole mobility as the third *** EQE values of optimal ternary PM-PPDs are increased to 105,000%at 360 nm,40,000%at 630 nm and 31,800%at 850 nm under-15 V bias,benefiting from the enhanced hole transport in ternary active *** optimal ternary PM-PPDs were successfully applied in a light-controlled circuit to turn on or turn off light emitting diode(LED).

关键词： polymer photodetectors photomultiplication external quantum efficiency broadband

A Principal Component Analysis(PCA)-based framework for automated variable selection in geodemographic classification

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Geo-Spatial Information Science 2019年第4期22卷 251-264,I0003页

作者： Yunzhe liu alex Singleton Daniel Arribas-Bel Geographic Data Science Lab Department of Geography and PlanningUniversity of LiverpoolLiverpoolUK

A geodemographic classification aims to describe the most salient characteristics of a small area zonal ***,such representations are influenced by the methodological choices made during their *** particular debate are the choice and specification of input variables,with the objective of identifying inputs that add value but also aim for model *** this context,our paper introduces a principal component analysis(PCA)-based automated variable selection methodology that has the objective of identifying candidate inputs to a geodemographic classification from a collection of *** proposed methodology is exemplified in the context of variables from the UK 2011 Census,and its output compared to the Office for National Statistics 2011 Output Area Classification(2011 OAC).Through the implementation of the proposed methodology,the quality of the cluster assignment was improved relative to 2011 OAC,manifested by a lower total withincluster sum of square *** the UK,more than 70.2%of the Output Areas(OAs)occupied by the newly created classification(***-OAC)outperform the 2011 OAC,with particularly strong performance within Scotland and Wales.

关键词： Geodemographics variable selection UK census spatial data mining principal component analysis