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Optimization of Stealthwatch Network Security System for the Detection and mitigation of Distributed Denial of Service (DDoS) Attack: Application to Smart Grid System

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Communications and Network 2024年第3期16卷 108-134页

作者： Emmanuel S. Kolawole Penrose S. Cofie John H. Fuller Cajetan m. Akujuobi Emmanuel A. Dada Justin F. Foreman Pamela H. Obiomon Electrical and Computer Engineering Department Prairie View A&M University Prairie View TX USA

The Smart Grid is an enhancement of the traditional grid system and employs new technologies and sophisticated communication techniques for electrical power transmission and distribution. The Smart Grid’s communication network shares information about status of its several integrated IEDs (Intelligent Electronic Devices). However, the IEDs connected throughout the Smart Grid, open opportunities for attackers to interfere with the communications and utilities resources or take clients’ private data. This development has introduced new cyber-security challenges for the Smart Grid and is a very concerning issue because of emerging cyber-threats and security incidents that have occurred recently all over the world. The purpose of this research is to detect and mitigate Distributed Denial of Service [DDoS] with application to the Electrical Smart Grid System by deploying an optimized Stealthwatch Secure Network analytics tool. In this paper, the DDoS attack in the Smart Grid communication networks was modeled using Stealthwatch tool. The simulated network consisted of Secure Network Analytic tools virtual machines (Vms), electrical Grid network communication topology, attackers and Target Vms. Finally, the experiments and simulations were performed, and the research results showed that Stealthwatch analytic tool is very effective in detecting and mitigating DDoS attacks in the Smart Grid System without causing any blackout or shutdown of any internal systems as compared to other tools such as GNS3, NeSSi2, NISST Framework, OmNeT++, INET Framework, ReaSE, NS2, NS3, m5 Simulator, OPNET, PlC & TIA Portal management Software which do not have the capability to do so. Also, using Stealthwatch tool to create a security baseline for Smart Grid environment, contributes to risk mitigation and sound security hygiene.

关键词： Smart Grid System Distributed Denial of Service (DDoS) Attack Intrusion Detection and Prevention Systems Detection mitigation and Stealthwatch

Which metrics drive macroinvertebrate drift in neotropical sky island streams?

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Water Biology and Security 2023年第1期2卷 1-8页

作者： marcos Callisto Diego m.P.Castro marden S.linares laryssa K.Carvalho Jose E.l.Barbosa Robert m.Hughes Universidade Federal de minas Gerais Instituto de Ci^encias BiologicasDepartamento de GeneticaEcologia e Evoluç~aoLaboratorio de Ecologia de BentosCP 486Av.Ant^onio Carlos6627PampulhaBelo HorizonteMGCEP 31270-901Brazil laboratorio de Ecologia Aquatica Departamento de BiologiaCentro de Ci^encias.Biologicas e da SaúdeUniversidade Estadual da ParaíbaAv.das Bananeiras351BodocongoCampina GrandePBCEP 58429-500Brazil Amnis Opes Institute 2895 SE GlennCorvallisOR97333-2169USA Department of Fisheries Wildlife&Conservation Sciences104 Nash HallCorvallisOR97331-3803USA Universidade Federal de lavras Departamento de Ecologia e Conservaç~aoPrograma de Pos Graduaç~ao em Ecologia AplicadaCEP 37200-900LavrasMinas GeraisBrazil

Despite long-standing interest,the mechanisms driving aquatic macroinvertebrate drift in tropical streams remain poorly ***,the objective of this study was to evaluate which environmental metrics drive macroinvertebrate drift in neotropical sky island *** evaluated whether altitude,the abundance of food resources,and variations in water quality influenced macroinvertebrate drift density,diversity,richness,and functional feeding *** hypothesis was developed to test whether increased altitude,lower food availability(particulate organic matter),and discharge would increase the density,taxonomic richness,and diversity of drifting *** headwater stream sites were sampled in the rainy and dry seasons in the Espinhaço meridional mountain Range(EmmR)of southeast *** were collected using drift nets deployed from 5:00 *** 8:00 *** abundance of food resources was assessed through estimates of coarse(CPOm)and fine(FPOm)particulate organic matter,and primary *** availability was an important explanatory variable for Gathering-Collectors and Scrapers,Altitude was important for Shredders and Predators,and Filtering-Collectors were linked to water discharge,suggesting that functional group drift masses were linked to different ecosystem *** temperature,conductivity,dissolved oxygen,current velocity,FPOm biomass and microbasin elevation range exerted little influence on macroinvertebrate *** taxa composition,this study also found that Baetidae and leptohyphidae(Ephemeroptera)and Chironomidae and Simuliidae(Diptera)were the most abundant groups drifting.

关键词： Biodiversity conservation Stream processes macroinvertebrate functional groups Water quality Serra do espinhaço

Teaching and learning Chinese through Immersion:A Case Study from the North American Context

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Frontiers of Education in China 2020年第1期15卷 99-141页

作者： Chan lÜ Department of Asian languages&literature University of WashingtonSeattleWA 98195-3521USA

With the promise of achieving bilingualism,biliteracy,and cultural pluralism,Chinese immersion programs for students from kindergarten to 12th grade(K-12)in North America,especially the US,have been proliferating in the past two *** on this rapidly growing population of non-native Chinese learners is also *** research synthesis focuses on 35 selected studies published in recent years on Chinese immersion in both Chinese and English language journals and *** review found that researchers are exploring a wide range of issues with respect to language and literacy development in Chinese immersion programs,including academic achievement in English,language and literacy acquisition in Chinese,instructional strategies and classroom interaction,as well as learners’language use and its sociolinguistic *** studies reflect a growing interest in and demand for learning more about the lesser-researched Chinese foreign language(CFl)learner population,and this review concludes with suggestions for future research on Chinese immersion based on its curricular features as well as specific considerations for conducting research with young,emergent bilingual and biliterate learners.

关键词： K-12 education Chinese immersion programs Chinese as a foreign language(CFl) academic achievement bilingual and biliteracy acquisition instructional strategies classroom interaction learner language

Reactivity of N-cyanoalkyl-substituted imidazolium halide salts by simple elution through an azide anion exchange resin

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Science China Chemistry 2012年第8期55卷 1683-1687页

作者： DRAB David m. KEllEY Steven P. SHAmSHINA Julia l. SmIGlAK marcin COJOCARU O. Andreea GURAU Gabriela ROGERS Robin D. Center for Green manufacturing and Department of Chemistry The University of Alabama Tuscaloosa AL 35487 USA

Certain N-cyanoalkyl-functionalized imidazolium halide salts unexpectedly undergo nitrile hydrolysis to amides, as well as dipolar cycloaddition to tetrazoles when eluted on azide anion exchanged resin.

关键词： multi-heterocycles ionic liquids azide exchange column nitrile cycloaddition tetrazoles imidazolium halide

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番茄新品种‘圆红212’

园艺学报 2024年第6期51卷 1435-1436页

作者：王永珍张剑国刘彩虹李思蓓吕甜甜山西农业大学园艺学院太原030031

‘圆红212’番茄是用自交系‘B69-29’作母本,‘S70-42’作父本配制的一代杂种。无限生长类型,中熟,植株生长势强,节间长度中等,叶片深绿色,叶量中等,第7~8节着生第1花序,单式花序为主,成熟果红色,扁圆形,果形指数0.77,果脐小,单果165~2... 详细信息

‘圆红212’番茄是用自交系‘B69-29’作母本,‘S70-42’作父本配制的一代杂种。无限生长类型,中熟,植株生长势强,节间长度中等,叶片深绿色,叶量中等,第7~8节着生第1花序,单式花序为主,成熟果红色,扁圆形,果形指数0.77,果脐小,单果165~270 g,果实硬度高(5.9 kg·cm^(-2)),果实可溶性固形物含量5.1%。产量97.5 t·hm^(-2)以上。耐贮运。抗番茄花叶病毒、黄瓜花叶病毒和叶霉病。适宜在北京、上海、辽宁、山东、山西、内蒙古、河南、湖南、四川和广东等地区春夏茬设施种植。

关键词：番茄杂种一代品种

STUDY ON PREPARATION, COmPlEX PERmITTIVITY,PERmEABIlITY AND mICROWAVE PROPERTIES OF BaZnzCo(2-z)Fe16O27/SiO2 mICROCRYSTAllINE GlASS CERAmICS

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Acta metallurgica Sinica(English letters) 2003年第6期16卷 421-427页

作者： H.J.Zhang X.l.Jia X.Yao l.Y.Zhang HighTemperatureCeramicsInstitute ZhengzhouUniversityZhengzhou450052China FunctionalmaterialsResearchlaboratory TongjiUniversityShanghai200092China

BaZnzCo2-zFe16O27/SiO2 microcrystalline glass ceramics with Z=0.0, 0.5, 0.8 and 1.1 were prepared at temperature 1200℃ for 5h by citrate sol-gel process. The complex dielectric constant and complex permeability of BaZnzCo2-zFe16 O27/SiO2-paraffin wax composites had been measured. Both the complex dielectric constant and dielectric loss exhibit almost no variation with frequency in 0.1-6.0GHz. The real part of permeability decreases with increasing frequency for all samples, and the imaginary part of permeability exhibits a clear resonance peak at 1.44GHz for Co2 W/SiO2, 1.32GHz for Zn0.5Co1.5 W/SiO2, 1.20GHz for Zn0.8Co1.2W/SiO2, and 1.08GHz for Zn1.1 Co0.9 W/SiO2. It is also showed that the content of zinc has a close effect on the magnetic properties of BaZnzCo2-zFe16O27/SiO2 microcrystalline glass ceramics, the greater the zinc content, the higher the values of imaginary part of permeability and magnetic loss.

关键词： BaZnz Co2-zFe16O27/SiO2 microcrystalline glass ceramics,sol-gel microwave property

SYNTHESIS AND ￣(183)W NmR CHARACTERIZATION OF P_4W_(30)Al_4 (H_2O)_2O_(112)￣(20-) HETEROPOlYANION

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Chinese Chemical letters 1995年第5期6卷 453-454页

作者： meng, l liu, JF NE Normal Univ Dept Chem Changchun 130024 Peoples R China

A trivacant heteropolytungstate derivative P4W30Al4 (H2O) 2O11220-has been synthesized from the lacunary precursor Na12 [α-P2W15O56]24H2O and characterized by IR. polarogram and 183W NmR spectrum 183W NmR of the title anion consists of eight lines with intensity ratio 1: 2: 2: 2: 2: 2: 2: 2 as expected for the dimeric Dawson- typed anion with C2h symmetry.

关键词： NmR CHARACTERIZATION SYNTHESIS OF H2O Al4 AND

基于飞机观测的华北降水云系上升气流区微结构研究

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大气科学 2024年第2期48卷 431-444页

作者：王心怡牛生杰吕晶晶王元靳雨晨邬昊鹏南京信息工程大学气象灾害预报预警与评估协同创新中心/中国气象局气溶胶与云降水重点开放实验室南京210044 南京工业大学安全科学与工程学院南京211816 中国气象局旱区特色农业气象灾害监测预警与风险管理重点实验室银川750002

上升气流是成云致雨的基本条件之一。本文利用河北省2017年5月一次层积混合云的机载云物理探测系统测量资料,研究了云中上升气流速度分布,云微结构特征以及二者的相关性。结果表明:云中上升气流速度随高度呈抛物线型分布,云底部较小(0.7... 详细信息

上升气流是成云致雨的基本条件之一。本文利用河北省2017年5月一次层积混合云的机载云物理探测系统测量资料,研究了云中上升气流速度分布,云微结构特征以及二者的相关性。结果表明:云中上升气流速度随高度呈抛物线型分布,云底部较小(0.75±0.52 m s^(−1)),云中部最大(3.64±2 m s^(−1)),云顶部最小(0.32±0.29 m s^(−1));发现随高度增加,云中上升气流区内冰粒子形状依次以片状、针状、柱状为主;暖云上升气流区中,上升气流速度与液态含水量正相关,相关系数为0.61;强垂直气流条件下云滴数浓度、最大云滴尺度大于弱垂直气流相应的数值,强垂直气流云粒子谱更符合Г函数分布。

关键词：降水云系飞机观测上升气流区云微物理结构

Supplemental material: Probe knots and Hopf insulators with ultracold atoms

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Chinese Physics letters 2018年第1期 46-48页

作者： Dong-ling Deng Sheng-Tao Wang Kai Sun l.-m.Duan Department of Physics University of Michigan Condensed matter Theory Center and Joint Quantum Institute Department of Physics University of Maryland Center for Quantum Information IIIS Tsinghua University Department of Physics Harvard University

*** COORDINATES AND A SKETCH OF THE KNOTTED SPIN TEXTURE For Hopf insulators in a cubic lattice,the first Brillouin zone（BZ）is a 3D torus T;.Since it is not convenient to draw and visualize different knots and links... 详细信息

关键词： Probe knots and Hopf insulators with ultracold atoms Supplemental material