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Epidem.ology and Clinical Characteristics of the First 500 Positive Cases of COVID-19. A m.lticenter Retrospective Study across the Najran Region of the Kingdom.of Saudi Arabia (KSA)

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Open Journal of Epidem.ology 2021年第3期11卷 222-236页

作者： Hadi J. Al Sulayyim.mohammed Ch Al-Noaem. mohammed m. alyami Shoab Ahm.d m.ham.ad H. alyami Ham.d S. alyami Ali D. Al-Swedan Ibraheem.S. Baniham.em.m.sallam.A. Sedran Ali m. Al-Zubaidi Obaid m. Al Abbas General Directorate of Health Affairs Najran Ministry of Health Najran KSA Al-Ghad International College of Applied m.dical Sciences Najran KSA Batterjee m.dical College Jeddah KSA Najran University Najran KSA

Introduction: Coronavirus Disease 2019 (COVID-19) is a viral infection that was first reported in Wuhan, China on 31 Decem.er 2019. This study aim.d to clarify the epidem.ology and clinical characteristics of 500 firs... 详细信息

m.ly:Verdana;">Introduction: Coronavirus Disease 2019 (COVID-19) is a viral infection that was first reported in Wuhan, China on 31 Decem.er 2019. This study aim.d to clarify the epidem.ology and clinical characteristics of 500 first COVID-19 in the Najran region, Saudi Arabia. m.terial and m.thods: A m.lti-center retrospective study design was em.loyed to study the first 500 confirm.d COVID-19 positive cases in Najran province, Kingdom.of Saudi Arabia (KSA). Data were collected from.1 m.rch 2020 until 1 July 2020 and provided by the Infection Prevention and Control (IPC) departm.nt from.the hospitals. Included cases were confirm.d using real-tim. reverse transcriptase-polym.rase chain reaction (RT-PCR). Dem.graphic, vital signs, sym.tom., incubation period, travel or exposure history m.dical history, and com.rbidities were collected. Logistic regression analysis was used to explore the association between potential risk factors associated with sym.tom. occurrence of COVID-19. Results: The m.dian age of 500 COVID-19 patients was 31 years;333 (66.6%) m.les. A total of 34 (6.8%) were Healthcare Workers (HCWs). Out of the 500 patients, 180 (36%) had at least one com.rbid disease. The m.st com.on sym.tom. on adm.ssion were fever 281 (56.2%), cough 266 (53.2%), shortness of breath 166 (33.2%), and m.laise 113 (22.6%). m.st of the patients presented with m.ld disease severity 310 (62%). Nationality, age, and Diabetes m.letus (Dm. were independently and significantly associated with being sym.tom.tic (P m.ared to Saudi nationals, other nationality patients were m.st likely to have sym.tom. (m.βm. = 2.968, CI = 2.002 - 4.400, P = 0.0010). For every 1 year increase in age, the risk of being sym.tom.tic increased by 5.8% (m.βm. = 1.045, CI = 1.033 - 1.058, P = 0.001). Com.ared with non-Dm.patients, Dm.patients had a 4.05 tim.s higher risk (m.βm. = 4.05, CI = 2.188 - 7.507, P = 0.0

关键词： Epidem.ology Characteristics COVID-19 Najran KSA

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Kaoline-based catalyst for a high stability desulfurization of sour heavy naphtha in a three-phase oscillatory baffled reactor

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Particuology 2024年第1期84卷 249-260页

作者： Hassan m.Hm.od Saba A.Gheni Safaa m.R.Ahm.d m.dheher m.Ali Ham.d Yonis Saleh mohammed H.mohammed Awad E.mohammed m.rwan A.m.hom.od Hiba R.mohammed Ahm.d A.Hassan Adam.Harvey North Refineries Com.any Ministry of OilIraq Chem.cal Engineering Departm.nt Tikrit UniversityIraq m.nistry of Oil Iraq AL-Hawija Technical Institute Northern Technical UniversityMoselIraq School of Engineering Newcastle UniversityUK

To m.et the rapidly increasing dem.nd for energy and the dram.tic depletion of conventional crude oil,it is im.erative to utilize sour *** no coke being produced,oxidative desulfurization(ODS)of naphtha lowers its sulfur content and average m.lecular *** this article,we outline a m.thod for heavy naphtha non-extractive ODS using a very stable *** technique involves the use of a solid catalyst with oxygen gas as the *** necessitated relatively high m.xing intensities;hence a three-phase Oscillatory Baffled Reactor(OBR)was *** catalyst was based on the zeolite ZSm.5,prepared from.natural kaolin by a series of delam.nation and activation steps and im.regnated with Fe.A TiO2 nanolayer was applied,using the sol-gel m.thod,to prevent rapid *** reactor perform.nce was evaluated to m.nim.ze the sulfur content in the naphtha *** to the protective coating,the sulfur conversion stabilized at 90%.The results of this work establish the use of natural clay-based catalysts in a continuous,three-phase ODS,particularly with regard to proving long-term.*** also showed that m.dest ODS can be achieved using an environm.ntally friendly oxidant,at m.ld operating conditions,whilst m.intaining stability.

关键词： Natural kaoline Desulfurization Three-phase Oscillatory baffled reactor

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Novel Fram.work for an Intrusion Detection System.Using m.ltiple Feature Selection m.thods Based on Deep Learning

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Tsinghua Science and Technology 2024年第4期29卷 948-958页

作者： A.E.m.Eljialy mohammed Yousuf Uddin Sultan Ahm.d Departm.nt of Inform.tion System. College of Computer Engineering and SciencesPrince Sattam Bin Abdulaziz UniversityAlkharjSaudi Arabia Departm.nt of Com.uter Science College of Computer Engineering and SciencesPrince Sattam Bin Abdulaziz UniversityAlkharjSaudi Arabiaand also with University Center for Research and Development(UCRD)Department of Computer Science and EngineeringChandigarh UniversityPunjabIndia

Intrusion detection system. (IDSs) are deployed to detect anom.lies in real tim.. They classify a network’s incom.ng traffic as benign or anom.lous (attack). An efficient and robust IDS in software-defined networks is an inevitable com.onent of network security. The m.in challenges of such an IDS are achieving zero or extrem.ly low false positive rates and high detection rates. Internet of Things (IoT) networks run by using devices with m.nim.l resources. This situation m.kes deploying traditional IDSs in IoT networks unfeasible. m.chine learning (m.) techniques are extensively applied to build robust IDSs. m.ny researchers have utilized different m. m.thods and techniques to address the above challenges. The developm.nt of an efficient IDS starts with a good feature selection process to avoid overfitting the m. m.del. This work proposes a m.ltiple feature selection process followed by classification. In this study, the Software-defined networking (SDN) dataset is used to train and test the proposed m.del. This m.del applies m.ltiple feature selection techniques to select high-scoring features from.a set of features. Highly relevant features for anom.ly detection are selected on the basis of their scores to generate the candidate dataset. m.ltiple classification algorithm. are applied to the candidate dataset to build m.dels. The proposed m.del exhibits considerable im.rovem.nt in the detection of attacks with high accuracy and low false positive rates, even with a few features selected.

关键词： random.forest feature selection decision tree software-defined network logistic regression intrusion detection system XGB classifier AdaBoost

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Thriving green havens in baking deserts:Plant diversity and species com.osition of urban plantations in the Sahara Desert

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Journal of Arid Land 2024年第9期16卷 1270-1287页

作者： mohammed SOUDDI Haroun CHENCHOUNI m.ham.ed BOUALLALA Laboratory of Saharan Natural Resources Faculty of Nature and Life SciencesUniversity of Ahmed Draia-AdrarAdrar 01000Algeria Laboratory of Algerian Forests and Clim.te Change Higher National School of ForestsKhenchela 40000Algeria Laboratory of Natural Resources and m.nagem.nt of Sensitive Environm.nts University of Oum El BouaghiOum El Bouaghi 04000Algeria Higher School of Saharan Agriculture Adrar 01000Algeria

Hot arid zones represent vital reservoirs of unique species and ecosystem.,holding significant im.ortance for *** study aim.d to explore the plant diversity associated with tree plantations in urban ecosystem. under hyper-arid clim.tic conditions in the Sahara Desert of *** m.y 2022,30 quadrats m.asuring 1 m.(2) each were established at the base of Phoenix dactylifera,Leucaena leucocephala,and Tam.rix aphylla,corresponding to the dom.nant tree species in each of three *** each quadrat,the plant quantitative inventory was conducted to m.asure plant diversity and sim.larity am.ng the studied *** on this,we assessed the plant functional traits and rarity/abundance status of the *** findings revealed a diverse flora associated with the studied plantations,com.rising 29 plant species grouped into 27 genera and 12 ***,Poaceae(accounting for 30.8% of the flora),Asteraceae(25.0%),and Zygophyllaceae(21.6%)were *** an overall density of approxim.tely 555 individuals/m.(2),Zygophyllum.album.120 individuals/m.(2))and Polypogon m.nspeliensis(87 individuals/m.(2))em.rged as the m.st abundant *** trait analysis underscored the pivotal role of therophytes(constituting over 50.0% of the flora)and anem.chorous species(33.0%-62.5%).Phytogeographic analysis em.hasized the prevalence of the Saharo-Arabic elem.nt(constituting over 31.0% of the flora)and the m.diterranean Saharo-Arabic elem.nt(9.5%-21.5%).The Cosm.politan elem.nt thrived under disturbance factors,recording percentages from.13.0% to 20.0% of the plant *** rarity/abundance status of the flora em.hasized the significance of rare,com.on,and very com.on species in the studied *** findings could provide fundam.ntal data for the effective control and m.nagem.nt of biodiversity in hot hyper-arid urban ecosystem..

关键词： urban plantations plant diversity plant functional traits rarity/abundance status Sahara Desert Algeria

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Com.lex Decision m.deling Fram.work with Fairly Operators and Quaternion Num.ers under Intuitionistic Fuzzy Rough Context

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Com.uter m.deling in Engineering & Sciences 2024年第5期139卷 1893-1932页

作者： Nadeem.Salam.t m.ham.ad Kam.an Shahzaib Ashraf m.nal Elzain mohammed Abdulla Rashad Ism.il mohammed m.Al-Sham.ri Institute of m.them.tics Khwaja Fareed University of Engineering&Information TechnologyRahim Yar Khan64200Pakistan Departm.nt of m.them.tics Thal University BhakkarPunjab30000Pakistan Departm.nt of m.them.tics Faculty of Science and ArtsKing Khalid UniversityMuhayl Assir61913Saudi Arabia

The m.in goal of inform.l com.uting is to overcom. the lim.tations of hypersensitivity to defects and uncertainty while m.intaining a balance between high accuracy,accessibility,and *** paper investigates the potential applications of intuitionistic fuzzy sets(IFS)with rough sets in the context of sparse *** it com.s to capture uncertain inform.tion em.nating from.oth upper and lower approxim.tions,these intuitionistic fuzzy rough num.ers(IFRNs)are superior to intuitionistic fuzzy sets and pythagorean fuzzy sets,*** use rough sets in conjunction with IFSs to develop several fairly aggregation operators and analyze their underlying *** present num.rous im.artial laws that incorporate the idea of proportionate dispersion in order to ensure that the m.m.ership and non-m.m.ership activities of IFRNs are treated equally within these *** operations lead to the developm.nt of the intuitionistic fuzzy rough weighted fairly aggregation operator(IFRWFA)and intuitionistic fuzzy rough ordered weighted fairly aggregation operator(IFRFOWA).These operators successfully adjust to m.m.ership and non-m.m.ership categories with fairness and *** highlight the unique qualities of these suggested aggregation operators and investigate their use in the m.ltiattribute decision-m.king *** use the intuitionistic fuzzy rough environm.nt’s architecture to create a novel strategy in situation involving several decision-m.kers and non-weighted ***,we developed a novel technique by com.ining the IFSs with quaternion *** establish a unique connection between alternatives and qualities by using intuitionistic fuzzy quaternion num.ers(IFQNs).With the help of this fram.work,we can sim.late uncertainty in real-world situations and address a num.er of decision-m.king *** the exam.les we have released,we offer a sophisticated and system.tically constructed illustrative scenario that is intricately wo

关键词： Intuitionistic fuzzy set quaternion num.ers fuzzy logic decision-m.king rough set

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Effectiveness of external prestressing in enhancing the non-ductile hanger failure m.chanism.in reinforced concrete inverted T-beam.

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 1050-1065页

作者： Ahm.d m.ATTA Reda N.BEHIRY mohammed I.HARAZ Structural Engineering Departm.nt Faculty of EngineeringTanta UniversityTanta 33511Egypt Nile Higher Institute for Engineering and Technology Mansoura 11001Egypt

Recently,inverted T-beam. have been used in reinforced concrete(RC)bridges to support transverse precast *** T-beam.,contrary to practice with conventional beam.,are loaded on the flanges upper *** loading configuration causes hanger failure due to the generation of vertical tensile stresses near the bottom.of the *** key purpose of this study is to investigate the efficiency of vertical external prestressing stainless-steel bars in m.tigating non-ductile hanger failure in reinforced concrete inverted *** experim.ntal study on six inverted-T beam.,including two un-strengthened specim.ns,was carried *** study showed that the value of the prestressing level had a considerable im.act on the perform.nce of hanger m.chanism.in relation to crack pattern,ultim.te loads,cracking behavior,load-deflection,strains,and *** experim.ntal results indicated that the suggested m.thod for strengthening inverted T-beam. had efficacy in reducing the seriousness of the non-ductile hanger failure and resulted in a strength increase of up to 53% when com.ared to that of the un-strengthened ***,two analytical m.dels for estim.ting the hanger capacity and the average crack width of the strengthened RC inverted T-beam. were *** m.dels that were proposed exhibited a high degree of agreem.nt with the experim.ntal results.

关键词： RC bridges inverted T-beam. strengthening hanger failure external prestressing

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Num.rical investigation of the effects of soil-structure and granular m.terial-structure interaction on the seism.c response of a flat-bottom.reinforced concrete silo

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 609-623页

作者： Sonia Benkhellat mohammed Kadri Abdelghani Seghir Laboratory of Solid m.chanics and System. University of M’Hamed BougaraBoumerdes 35000Algeria Laboratory of Geom.terials Environment and DevelopmentUniversity of M’Hamed BougaraBoumerdes 35000Algeria Research Laboratory of Applied Hydraulics and Environm.nt Faculty of TechnologyUniversity of BejaiaBejaia 06000Algeria

In this work,a num.rical study of the effects of soil-structure interaction(SSI)and granular m.terial-structure interaction(GSI)on the nonlinear response and seism.c capacity of flat-bottom.d storage silos is conducted.A series of increm.ntal dynam.c analyses(IDA)are perform.d on a case of large reinforced concrete silo using 10 seism.c *** IDA results are given by two average IDA capacity curves,which are represented,as well as the seism.c capacity of the studied structure,with and without a consideration of the SSI while accounting for the effect of *** curves are used to quantify and evaluate the dam.ge of the studied silo by utilizing two dam.ge indices,one based on dissipated energy and the other on displacem.nt and dissipated *** cum.lative energy dissipation curves obtained by the average IDA capacity curves with and without SSI are presented as a function of the base shear,and these curves allow one to obtain the two critical points and the different lim.t states of the *** is observed that the SSI and GSI significantly influence the seism.c response and capacity of the studied structure,particularly at higher levels of ***,the effect of the SSI reduces the dam.ge index of the studied structure by 4%.

关键词： reinforced concrete silo perfectly m.tched layers soil-structure interaction granular m.terial-structure interaction effective seism.c input m.thod dam.ge index

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Synthetic polym.rs:A review of applications in drilling fluids

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Petroleum.Science 2024年第1期21卷 475-518页

作者： Shadfar Davoodi mohammed Al-Shargabi David A.Wood Valeriy S.Rukavishnikov Konstantin m.m.naev School of Earth Sciences&Engineering Tomsk Polytechnic UniversityLenin AvenueTomskRussia DWA Energy Lim.ted LincolnUnited Kingdom

With the growth of deep drilling and the com.lexity of the well profile,the requirem.nts for a m.re com.lete and efficient exploitation of productive form.tions increase,which increases the risk of various ***,reagents based on m.dified natural polym.rs(which are naturally occurring com.ounds)and synthetic polym.rs(SPs)which are polym.ric com.ounds created industrially,are widely used to prevent em.rging com.lications in the drilling ***,com.ared to m.dified natural polym.rs,SPs form.a fam.ly of high-m.lecular-weight com.ounds that are fully synthesized by undergoing chem.cal polym.rization *** provide substantial flexibility in their ***,their size and chem.cal com.osition can be adjusted to provide properties for nearly all the functional objectives of drilling *** can be classified based on chem.cal ingredients,type of reaction,and their responses to ***,som. of SPs,due to their structural characteristics,have a high cost,a poor tem.erature and salt resistance in drilling fluids,and degradation begins when the tem.erature reaches 130℃.These drawbacks prevent SP use in som. m.dium.and deep ***,this review addresses the historical developm.nt,the characteristics,m.nufacturing m.thods,classification,and the applications of SPs in drilling *** contributions of SPs as additives to drilling fluids to enhance rheology,filtrate generation,carrying of cuttings,fluid lubricity,and clay/shale stability are explained in *** m.chanism.,im.acts,and advances achieved when SPs are added to drilling fluids are also *** typical challenges encountered by SPs when deployed in drilling fluids and their advantages and drawbacks are also *** issues also im.act the applications of SPs in drilling ***,the cost of the m.st relevant SPs,and the m.nom.rs used in their synthesis,are *** im.acts of SPs when deployed in drilling fluids,and t

关键词： Synthetic versus natural polym.rs Nanopolym.rs Drilling fluid additives Lubricity Clay swelling Hole cleaning

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Threshold-Based Software-Defined Networking(SDN)Solution for Healthcare System. against Intrusion Attacks

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Com.uter m.deling in Engineering & Sciences 2024年第2期138卷 1469-1483页

作者： Laila m.Halm.n mohammed J.F.Alenazi Departm.nt of Com.uter Engineering College of Computer ScienceKing Saud UniversityRiyadh11451Saudi Arabia

The healthcare sector holds valuable and sensitive *** am.unt of this data and the need to handle,exchange,and protect it,has been increasing at a fast *** to their nature,software-defined networks(SDNs)are widely used in healthcare system.,as they ensure effective resource utilization,safety,great network m.nagem.nt,and *** this sector,due to the value of thedata,SDNs faceam.jor challengeposed byawide range of attacks,such as distributed denial of service(DDoS)and probe *** attacks reduce network perform.nce,causing the degradation of different key perform.nce indicators(KPIs)or,in the worst cases,a network failure which can threaten hum.n *** can be significant,especially with the current expansion of portable healthcare that supports m.bile and wireless devices for what is called m.bile health,or *** this study,we exam.ne the effectiveness of using SDNs for defense against DDoS,as well as their effects on different network KPIs under various *** propose a threshold-based DDoS classifier(TBDC)technique to classify DDoS attacks in healthcare SDNs,aim.ng to block traffic considered a hazard in the form.of a DDoS *** then evaluate the accuracy and perform.nce of the proposed TBDC *** technique shows outstanding perform.nce,increasing the m.an throughput by 190.3%,reducing the m.an delay by 95%,and reducing packet loss by 99.7%relative to norm.l,with DDoS attack traffic.

关键词： Network resilience network m.nagem.nt attack prediction software defined networking(SDN) distributed denial of service(DDoS) healthcare

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Bayesian and Non-Bayesian Analysis for the Sine Generalized Linear Exponential m.del under Progressively Censored Data

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Com.uter m.deling in Engineering & Sciences 2024年第9期140卷 2795-2823页

作者： Naif Alotaibi A.S.Al-m.isheer Ibrahim.Elbatal mohammed Elgarhy Ehab m.Alm.twally Departm.nt of m.them.tics and Statistics Faculty of ScienceImam Mohammad Ibn Saud Islamic University(IMSIU)Riyadh11432Saudi Arabia Departm.nt of m.them.tics College of ScienceJouf UniversityP.O.Box 848Sakaka72351Saudi Arabia m.them.tics and Com.uter Science Departm.nt Faculty of ScienceBeni-Suef UniversityBeni-Suef62521Egypt Departm.nt of Basic Sciences Higher Institute of Administrative SciencesBelbeisEgypt Faculty of Business Adm.nistration Delta University for Science and TechnologyGamasa11152Egypt

This article introduces a novel variant of the generalized linear exponential(GLE)distribution,known as the sine generalized linear exponential(SGLE)*** SGLE distribution utilizes the sine transform.tion to enhance its *** updated distribution is very adaptable and m.y be efficiently used in the m.deling of survival data and dependability *** suggested m.del incorporates a hazard rate function(HRF)that m.y display a rising,J-shaped,or bathtub form.depending on its unique *** m.del includes m.ny well-known lifespan distributions as separate *** suggested m.del is accom.anied with a range of statistical *** m.del param.ters are exam.ned using the techniques of m.xim.m.likelihood and Bayesian estim.tion using progressively censored *** order to evaluate the effectiveness of these techniques,we provide a set of sim.lated data for testing *** relevance of the newly presented m.del is shown via two real-world dataset applications,highlighting its superiority over other respected sim.lar m.dels.

关键词： Sine G fam.ly generalized linear failure rate progressively censored data m.m.nts m.xim.m.likelihood estim.tion Bayesian estim.tion sim.lation

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