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Spa.ia. Va.ia.ility a.d Ca.togra.hy of Ma.imum a.nua. Da.ly Ra.nfa.l under Different Return Periods in Northern a.geria

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Journa. of Mounta.n Science 2015年第6期12卷 1403-1421页

作者： MEDDI Moha.ed TOUMI samir Na.iona. High School of Hydra.lic (ENSH)

The estima.ion of precipita.ion qua.tiles ha. a.wa.s been a. a.ea.of grea. importa.ce to meteorologists, hydrologists, pla.ners a.d ma.a.ers of hydrotechnica. infra.tructures. In ma.y ca.es, it is necessa.y to estima.e the va.ues rela.ing to extreme events for the sites where there is little or no mea.urement, a. well a. their return periods. a.sta.istica. a.proa.h is the most used in such ca.es. It a.ms to find the proba.ility distribution tha. best fits the ma.imum da.ly ra.nfa.l va.ues. In our study, 231 ra.nfa.l sta.ions were used to regiona.ize a.d find the best distribution for modeling the ma.imum da.ly ra.nfa.l in Northern a.geria. The L-moments method wa. used to perform a.regiona.iza.ion ba.ed on discorda.ce criteria.a.d homogeneity test. It ga.e rise to twelve homogeneous regions in terms of LCoefficient of va.ia.ion(L-CV), L-Skewness(L-CS) a.d L-Kurtosis(L-CK). This sa.e technique a.lowed us to select the regiona. proba.ility distribution for ea.h group using the Z sta.istic. The genera.ized extreme va.ues distribution(GEV) wa. selected to model the ma.imum da.ly ra.nfa.l of 10 groups loca.ed in the north of the steppe region a.d the genera.ized logistic distribution(GLO) for groups representing the steppes of Centra. a.d Western a.geria. The study of uncerta.nty by the bia. a.d RMSE showed tha. the regiona. a.proa.h is a.cepta.le. We ha.e a.so developed ma.imum da.ly ra.nfa.l ma.s for 2, 5, 10, 20, 50 a.d 100 yea.s return periods. We relied on a.network of 255 ra.nfa.l sta.ions. The spa.ia. va.ia.ility of qua.tiles wa. eva.ua.ed by semi-va.iogra.s. a.l ra.nfa.l frequency models ha.e a.spa.ia. dependence with a. exponentia. model a.justed to the experimenta. semi-va.iogra.s. The pa.a.eters of the fitted semi-va.iogra. for different return periods a.e simila., throughout, while the nugget is more importa.t for high return periods. Ma.imum da.ly ra.nfa.l increa.es from South to North a.d from West to Ea.t, a.d is more significa.t in the coa.ta. a.ea. of ea

关键词： a.nua. ma.imum da.ly ra.nfa.l Regiona.isa.ion L-moments Ma.ping Northern a.geria

Re-eva.ua.ion of severa. hea.y meta.s remova. by na.ura. limestones

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Frontiers of Chemica. Science a.d Engineering 2014年第4期8卷 418-432页

作者： a.i SDIRI samir BOUa.IZ La.ora.ory of Wa.er Energy and Environment National Engineering School University of Sfax Sfax 1173-3038 Tunisia

Different trea.ment technologies ha.e been efficiently a.plied to remove hea.y meta.s from wa.te- wa.er. Efforts ha.e been ma.e to find out the most economic wa.er trea.ment technology by using low cost a.d ea.ily a.cessible na.ura. ma.eria.s. On the other ha.d, hea.y meta.s a.e the most threa.ening groundwa.er conta.ina.ts beca.se of their toxicity a.d ha.mful effects on huma. a.d biota. This review discusses the use of na.ura. geologica. ma.eria.s for hea.y meta. remova. in a.ueous systems. Specia. a.tention ha. been devoted to na.ura. limestone through a.systema.ic inventory of releva.t published reports. The remova. of toxic meta.s ma. include different mecha.isms （e.g., physisorption, chemisorptions, precipita.ion, etc.）, depending on the physico-chemica. properties of the ma.eria. a.d the removed meta.. Sorption of toxic meta.s （e.g., Pb, Cu, Cd, Zn, Cr, Hg, etc.） onto na.ura. limestone involved precipita.ion of meta. ca.bona.e a. a.predomina.t remova. process, but often subordina.ed by a.sorption a.d ion excha.ge, depending on the physico-chemica. properties of the studied limestone.

关键词： limestone hea.y meta.s sorption wa.te-wa.er pa.sive trea.ment technology

Fuzzy a.a.tive Control of a.Fra.tiona. Order Cha.tic System With Unknown Control Ga.n Sign Using a.Fra.tiona. Order Nussba.m Ga.n

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IEEE/Ca. Journa. of a.toma.ica.Sinica 2019年第3期6卷 816-823页

作者： Kha.ir Khetta. samir La.a.i Ya.sine Bensa.ia IEEE the Electrica. Engineering Depa.tment University of Mohamed Boudiaf M’sila 28000 Algeria Electrica. Engineering Depa.tment University of Skikda the EEa.Depa.tment National Polytechnic School of Constantine B. P. 75 A Ali Mendjli 25000 Constantine Algeria SP-La. La.ora.ory Department of Electronics Mentouri University Ya.sine Bensa.ia.is with the Electrica. Engineering Depa.tment University of Bouira

In this pa.er we propose a. improved fuzzy a.a.tive control stra.egy, for a.cla.s of nonlinea. cha.tic fra.tiona. order(SISO) systems with unknown control ga.n sign. The online control a.gorithm uses fuzzy logic sets for the identifica.ion of the fra.tiona. order cha.tic system, wherea. the la.k of a.priori knowledge on the control directions is solved by introducing a.fra.tiona. order Nussba.m ga.n. Ba.ed on Lya.unov sta.ility theorem, sta.ility a.a.ysis is performed for the proposed control method for a. a.cepta.le synchroniza.ion error level. In this work, the Gr ¨unwa.d-Letnikov method is used for numerica. a.proxima.ion of the fra.tiona. order systems. a.simula.ion exa.ple is given to illustra.e the effectiveness of the proposed control scheme.

关键词： a.a.tive fuzzy control cha.s synchroniza.ion fra.tiona. order Nussba.m function Lya.unov sta.ility nonlinea. fra.tiona. order systems

Numerica. study on discha.ge cha.a.teristics influenced by seconda.y electron emission in ca.a.itive RF a.gon glow discha.ges by fluid modeling

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Chinese Physics B 2018年第2期27卷 415-422页

作者：赵璐璐刘悦 Ta.ra.samir Key La.ora.ory of Ma.eria.s Modifica.ion by La.er Ion and Electron Beams (Ministry of Education) School of PhysicsDalian University of Technology School of Informa.ion Science a.d Engineering Dalian Polytechnic University

a.one-dimensiona.（1D） fluid model of ca.a.itive RF a.gon glow discha.ges between two pa.a.lel-pla.e electrodes a. low pressure is employed. The influence of the seconda.y electron emission on the pla.ma.cha.a.teristics in the discha.ges is investiga.ed numerica.ly by the model. The results show tha. a. the seconda.y electron emission coefficient increa.es,the cycle-a.era.ed electric field ha. a.most no cha.ge; the cycle-a.era.ed electron tempera.ure in the bulk pla.ma.a.most does not cha.ge, but it increa.es in the two shea.h regions; the cycle-a.era.ed ioniza.ion ra.e, electron density, electron current density, ion current density, a.d tota. current density a.l increa.e. a.so, the cycle-a.era.ed seconda.y electron fluxes on the surfa.es of the electrodes increa.e a. the seconda.y electron emission coefficient increa.es. The evolutions of the electron flux, the seconda.y electron flux a.d the ion flux on the powered electrode increa.e a. the seconda.y electron emission coefficient increa.es. The cycle-a.era.ed electron pressure hea.ing, electron Ohmic hea.ing, electron hea.ing, a.d ion hea.ing in the two shea.h regions increa.e a. the seconda.y electron emission coefficient increa.es. The cycle-a.era.ed electron energy loss increa.es with increa.ing seconda.y electron emission coefficient.

关键词： RF glow discha.ge seconda.y electron emission fluid model

Effects of ca.hodic component of current on porosity a.d ha.dness cha.a.teristics of micro pla.ma.oxida.ion(MPO) coa.ings on a.uminum a.loy

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中国有色金属学会会刊：英文版 2005年第1期15卷 113-118页

作者： samir Ha.id a.a. 钱翰城 School of Mecha.ica. Engineering Chongqing University Chongqing 400044 China

Micro pla.ma.oxida.ion(MPO) ha. recently been investiga.ed a. a.novel, ra.id a.d effective mea.s to provide modified surfa.es with improved properties of loa. bea.ing a.d wea. resista.ce on light a.loys pa.ticula.ly a.uminum a.loys. MPO is a.multifa.tor-controlled process, these fa.tors must be controlled to produce high qua.ity coa.ings. The ma.n resea.ch empha.is in MPO coa.ing development over the pa.t yea.s seems to be the a.ta.nment of higher ha.dness levels a.d thick coa.ings. The porosity of MPO coa.ing is the most complex phenomenon a.fecting the distribution, levels a.d the mea.urements of the ha.dness; a.d it is controlled by suita.le selection of importa.t pa.a.eters such a. the electrica. conditions. Cera.ics coa.ings were synthesized on a. substra.e by MPO to exa.ine the effects of a.ding a.ca.hodic pha.e a.terna.ed with a.odic-ca.hodic current on the porosity a.d ha.dness cha.a.teristics of coa.ings by X-ra. diffra.tion(XRD), sca.ning electron microscopy(SEM), a.d microha.dness tester. The coa.ings produced by the combined mode a.e more dense a.d less porous tha. tha. by the a.odic-ca.hodic mode. (Microha.dness) test shows tha. the coa.ings produced by the combined mode exhibit both the highest ha.dness, a.d less reduction percenta.e in ha.dness with increa.ing the coa.ings thickness. These improvements become more significa.t for the polished a.d thicker coa.ings.

关键词：微观等离子体氧化铝合金硬度多孔材料

Fa.lt tolera.t control ba.ed on neura. network interva. type-2 fuzzy sliding mode controller for octorotor Ua.

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Frontiers of Computer Science 2016年第4期10卷 657-672页

作者： samir ZEGHLa.HE Dja.el Sa.Ga. Ka.el Ka.A La.S La.ora.ory Departemenl: of Electronics Faculty of Technology University of MSila Msila 28000 Algeria SET La.ora.ory Departement of Electronics Faculty of Technology University of Blida Blida 09000 Algeria

In this pa.er, a.robust controller for a.six degrees of freedom （6 DOF） octorotor helicopter control is proposed in presence of a.tua.or a.d sensor fa.lts. Neura. networks （NN）, interva. type-2 fuzzy logic control （IT2FLC） a.proa.h a.d sliding mode control （SMC） technique a.e used to design a.controller, na.ed fa.lt tolera.t neura. network interva. type-2 fuzzy sliding mode controll,~r （FTNNIT2FSMC）, for ea.h subsystem of the octorotor helicopter. The proposed control scheme a.lows a.oiding difficult modeling, a.tenua.ing the cha.tering effect of the SMC, reducing the number of rules for the fuzzy controller, a.d gua.a.teeing the sta.ility a.d the robustness of the system. The simula.ion results show tha. the FTNNIT2FSMC ca. grea.ly a.levia.e the cha.tering effect, tra.king well in presence of a.tua.or a.d sensor fa.lts.

关键词： neura. networks type-2 fuzzy logic sliding mode controller fa.lt tolera.t control octorotor helicopter

Effects of ga. pressure on pla.ma.cha.a.teristics in dua. frequency a.gon ca.a.itive glow discha.ges a. low pressure by a.self-consistent fluid model

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Chinese Physics B 2017年第12期26卷 361-370页

a.self-consistent fluid model for dua. ra.io frequency a.gon ca.a.itive glow discha.ges a. low pressure is esta.lished. Numerica. results a.e obta.ned by using a.finite difference method to solve the model numerica.ly, a.d the results a.e a.a.yzed to study the effect of ga. pressure on the pla.ma.cha.a.teristics. It shows tha. when the ga. pressure increa.es from 0.3 Torr （1 Torr=1.33322102 Pa. to 1.5 Torr, the cycle-a.era.ed pla.ma.density a.d the ioniza.ion ra.e increa.e; the cycle-a.era.ed ion current densities a.d ion energy densities on the electrodes electrode increa.e; the cycle-a.era.ed electron tempera.ure decrea.es. a.so, the insta.ta.eous electron density in the powered shea.h region is presented a.d discussed. The cycle-a.era.ed electric field ha. a.complex beha.ior with the increa.ing of ga. pressure, a.d its cha.ges ta.e pla.e ma.nly in the two shea.h regions. The cycle-a.era.ed electron pressure hea.ing, electron ohmic hea.ing, electron hea.ing, a.d electron energy loss a.e a.l influenced by the ga. pressure. Two pea.s of the electron hea.ing a.pea. in the shea.h regions a.d the two pea.s become la.ger a.d move to electrodes a. the ga. pressure increa.es.

关键词： dua. frequency ga. pressure glow discha.ge

Pa.crea.ic pseudocyst

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World Journa. of Ga.troenterology 2009年第1期15卷 38-47页

作者： samir Ha.a.hi Peter V Dra.a.ov Depa.tment of Ga.troenterology Hepa.ology a.d Nutrition University of FloridaGainesville Florida 32610 United States

Pa.crea.ic pseudocysts a.e complica.ions of a.ute or chronic pa.crea.itis. Initia. dia.nosis is a.complished most often by cross-sectiona. ima.ing. Endoscopic ultra.ound with fine needle a.pira.ion ha. become the preferred test to help distinguish pseudocyst from other cystic lesions of the pa.crea.. Most pseudocysts resolve sponta.eously with supportive ca.e. The size of the pseudocyst a.d the length of time the cyst ha. been present a.e poor predictors for the potentia. of pseudocyst resolution or complica.ions, but in genera., la.ger cysts a.e more likely to be symptoma.ic or ca.se complica.ions. The ma.n two indica.ions for some type of inva.ive dra.na.e procedure a.e persistent pa.ient symptoms or the presence of complica.ions (infection, ga.tric outlet or bilia.y obstruction, bleeding). Three different stra.egies for pa.crea.ic pseudocysts dra.na.e a.e a.a.la.le: endoscopic (tra.spa.illa.y or tra.smura.) dra.na.e, percuta.eous ca.heter dra.na.e, or open surgery. To da.e, no prospective controlled studies ha.e compa.ed directly these a.proa.hes. a. a.result, the ma.a.ement va.ies ba.ed on loca. expertise, but in genera., endoscopic dra.na.e is becoming the preferred a.proa.h beca.se it is less inva.ive tha. surgery, a.oids the need for externa. dra.n, a.d ha. a.high long-term success ra.e. a.ta.lored thera.eutic a.proa.h ta.ing into considera.ion pa.ient preferences a.d involving multidisciplina.y tea. of thera.eutic endoscopist, interventiona. ra.iologist a.d pa.crea.ic surgeon should be considered in a.l ca.es.

关键词： Pa.crea.ic pseudocyst Cyst Pa.crea.ititis Endoscopic ultra.ound Thera.y

The Communist Ma.ifesto,170 Yea.s La.er

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学术界 2018年第11期 214-227页

作者： samir a.in French Ma.xia. Economist Director of the Third World Forum

No text written in the mid-nineteenth century ha. held the roa. until toda. a. well a. the Communist Ma.ifesto of *** is no a.y other text written in the middle of the 21th century which reta.ned va.idity until this da. a. well a. the Ma.ifesto of the Communist *** toda. entire pa.a.ra.hs of the text correspond to the contempora.y rea.ity even better tha. in *** from the premises which were ha.dly visible in the era.Ma.x a.d Engels drew the conclusions which the deployment of 170 yea.s of history fully *** this a.ticle I will give further enlightening exa.ples.

关键词： text written century premises