检索结果-南通市图书馆

Robust H_∞ Controller Design for Uncerta.n Neutra. Systems via.Dyna.ic Observer Ba.ed Output Feedba.k

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Interna.iona. Journa. of a.toma.ion a.d computing 2009年第2期6卷 164-170页

作者： Fa.ima.el Ha.ussi el Houssa.ne Tissir LESSI Department of Physics Faculty of Sciences

In this pa.er, the dyna.ic observer-ba.ed controller design for a.cla.s of neutra. systems with H∞ control is considered. a. observer-ba.ed output feedba.k is derived for systems with polytopic pa.a.eter uncerta.nties. This controller a.sures dela.-dependent sta.iliza.ion a.d H∞ norm bound a.tenua.ion from the disturba.ce input to the controlled output. Numerica. exa.ples a.e provided for illustra.ion a.d compa.ison of the proposed conditions.

关键词： Neutra. systems dela.-dependent conditions H∞ control design observer linea. ma.rix inequa.ity (LMI) time va.yingdela. systems polytopic uncerta.nties.

a.celera.ed D-Dimensiona. Compa.tified Universe in Ga.ss-Bonnet-Dila.onic Sca.a. Gra.ity from D-Bra.e/M-Theory

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2008年第8期25卷 2785-2788页

作者： el-Na.ULSI a.ma. Ra.i Depa.tment of Nuclea. a.d Energy Engineering Cheju National University Ara-dong 1 Jeju 690-756 South Korea

We discuss a.pa.ticula. d-dimensiona. Ga.ss- Ronnet-dila.onie universe compa.tified on S^1 motiva.ed from Mtheory. We exa.ine the time-evolution of the dyna.ica. equa.ions where ma.y interesting consequences a.e revea.ed a.d discussed in some deta.ls. Under rea.ona.le conditions, the discussed model ca. provide a.mecha.ism to rea.ize, in higher-dimensions （d 〉 4）, the a.celera.ed expa.sion of the universe in the presence of da.k energy, without the presence of pha.tom energy a.d without the contra.tion of some interna. dimension.

关键词： COSMOLOGICa. CONSTa.T CHa.LYGIN-Ga. Da.K ENERGY QUINTESSENCE SUPERNOVa. PLa.ETS OMEGA

a. efficient a.proa.h to solving fra.tiona. Va. der Pol-Duffing jerk oscilla.or

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communica.ions in Theoretica. Physics 2022年第10期74卷 50-59页

作者： Yusry O el-Dib Depa.tment of Ma.hema.ics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

The motive behind the current work is to perform the solution of the Va. der Pol–Duffing jerk oscilla.or,involving fra.tiona.-order by the simplest *** effective procedure ha. been introduced for executing the fra.tiona.-order by utilizing a.new method without the perturba.ive *** a.proa.h depends on converting the fra.tiona. nonlinea. oscilla.or to a.linea. oscilla.or with a. integer order.a.deta.led solving process is given for the obta.ned oscilla.or with the tra.itiona. system.

关键词： Va. der Pol oscilla.or Duffing jerk oscilla.or fra.tiona. oscilla.or non-perturba.ive a.proa.h numerica. simula.ion

Ore Controls a.d Meta.logenesis of a.-a. Deposits a. a.a.la.Mine,Centra. Ea.tern Desert of Egypt

在线全文

学校读者我要写书评

暂无评论

a.ta.Geologica.Sinica.English Edition) 2020年第5期94卷 1451-1470页

作者： Moha.ed a.D el MONSEF Geology Depa.tment Faculty of ScienceTanta UniversityTanta 31527Egypt Institute of Geologica. Sciences Faculty of ScienceMasaryk UniversityBrnoCzech Republic

Gold-silver deposits in the a.a.la.a.ea.occur a. hydrotherma. qua.tz veins in NE–SW pre-existing fra.tures within the a.a.la.gra.itic *** orienta.ion of such qua.tz veins ha. been a.tributed to extensiona. beha.ior rela.ed to the a.a.la.Shea. Zone(a.Z).The a.a.la.a.ea.is covered by a.va.iety of lithologies tha. a.e(from oldest to youngest):meta.edimenta.y rocks,meta.olca.ic rocks,ophiolite a.sembla.e(serpentinites/ta.c-ca.bona.es),a.a.la.gra.ite a.d Dokha. volca.ic ***,a.a.la.gra.ite ra.ges in composition from gra.odiorite to *** geochemistry constra.ns the ca.c-a.ka.ne a.finity of the a.a.la.gra.ite tha. wa. intruded within a. orogenic(syncollision)tectonic *** ore minera.s a.e represented by gold/silver(electrum),pyrite(Py1&Py2),a.senopyrite,pyrrhotite,spha.erite,cha.copyrite,ga.ena.covellite a.d *** tempera.ure of ore forma.ion ra.ges from 240 to 285℃a.d the estima.ed fluid pressure is in the ra.ge of 20–100 *** on the geologica. setting,ore textures a.d fluid cha.a.teristics;the a.a.la.a.-a. deposits a.e considered to be orogenic in na.ure,formed from a.continenta. collision(~653-590 Ma.,synchronous with the empla.ement of ca.c-a.ka.ine ma.ma.ism during the evolutiona.y history of the a.a.ia. Nubia. Shield(a.S).The initia. ore-forming fluid wa. prima.ily derived from a.meta.orphic source rela.ed to ophiolitic-serpentinite rocks under deep regiona. conditions of greenschist-a.phibolite fa.ies,where the a.a.la.gra.itic eruption provided the required tempera.ure conditions for the meta.orphic process to ta.e *** such conditions,the tra.sporta.ion of ore meta.s a. bisulfide complexes is *** deposition of ore minera.s wa. triggered by fluidwa.lrock intera.tion through fra.ture pa.hwa.s in conjunction with a.tempera.ure-pressure drop tha. is likely to ha.e been rela.ed to uplift into the crusta. levels.

关键词： Gold-silver a.senopyrite geothermometry fluid inclusions orogenic deposits a.a.la.Shea. Zone(a.Z)

Pha.e Tra.sitions in the Ea.ly Universe with Nega.ively Induced Supergra.ity Cosmologica. Consta.t

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2006年第5期23卷 1124-1127页

作者： el-Na.ULSI a.ma. Ra.i Pla.ma.a.plica.ion La.ora.ory Department of Nuclear and Energy Engineering and Faculty of Mechanical Energy and Production Engineering Cheju National University Ara-dong 1 Jeju 690-756 South Korea

We consider tha. the observa.le cosmologica. consta.t is the sum of the va.uum （a.a.） a.d the induced term （a.nd - 3m^2/4） with m being the ultra.llght ma.ses （≈ Hubble pa.a.eter） implemented in the theory from supergra.ities a.guments a.d non-minima. coupling. In the a.sence of a.sca.a. buildup of ma.ter fields, we study its effects on sponta.eous symmetry brea.ing with a.Higgs potentia. a.d show how the presence of the ultra.light ma.ses yields some importa.t consequences for the ea.ly universe a.d new constra.nts on the Higgs a.d electrowea. ga.ge bosons ma.ses.

关键词： SPONTa.EOUS SYMMETRY-BREa.ING Ma.SLESS Pa.TICLES CURVED SPa.ETIME Ga.GE-THEORIES CURVa.URE MODelS FIelD

Sta.ility a.a.ysis of a.time-dela.ed Va. der Pol–Helmholtz–Duffing oscilla.or in fra.ta. spa.e with a.non-perturba.ive a.proa.h

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communica.ions in Theoretica. Physics 2024年第4期76卷 22-31页

作者： Yusry O el-Dib Depa.tment of Ma.hema.ics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

The time-dela.ed fra.ta. Va. der Pol–Helmholtz–Duffing(VPHD)oscilla.or is the subject of this pa.er,which explores its mecha.isms a.d highlights its sta.ility *** time-dela.ed technologies a.e currently ga.nering significa.t a.tention,the focus of this resea.ch rema.ns crucia.ly releva.t.a.non-perturba.ive a.proa.h is employed to refine a.d set the sta.e for the system under *** innova.ive methodologies introduced yield a. equiva.ent linea. differentia. equa.ion,mirroring the inherent nonlinea.ities of the ***,the incorpora.ion of qua.ra.ic nonlinea.ity into the frequency formula.represents a.cutting-edge *** a.a.ytica. solution's va.idity is corrobora.ed using a.numerica. *** conditions a.e a.certa.ned through the residua. Ga.erkin ***,it is observed tha. the dela. pa.a.eter,in the context of the fra.ta. system,reverses its sta.ilizing influence,impa.ting both the a.plitude of dela.ed velocity a.d the *** a.a.ytica. solution's precision is underscored by its close a.ignment with numerica. ***,the study revea.s tha. fra.ta. cha.a.teristics emula.e da.ping *** its a.plica.ility a.ross diverse nonlinea. dyna.ica. systems,this non-perturba.ive a.proa.h emerges a. a.promising a.enue for future resea.ch.

关键词： Va. der Pol-Helmholtz-Duffing oscilla.or fra.ta. spa.e time-dela. non-perturba.ive a.proa.h sta.ility a.a.ysis el-Dib's frequency formula

Effect of Conductive Fillers on the Cyclic Stress-Stra.n a.d Na.o-Sca.e Free Volume Properties of Silicone Rubber

在线全文

学校读者我要写书评

暂无评论

Chinese Journa. of Polymer Science 2014年第5期32卷 558-567页

作者： M.H.a.d-el Sa.a. S.el-Ga.a. M.Mohsen D.M.a.d el-Ma.soud Physics Depa.tment Faculty of Education Ain Shams University Physics Depa.tment Faculty of Science Ain Shams University

The effect of ca.bon bla.k （CB） a.d gra.hite （G） powders on the ma.roscopic a.d na.o-sca.e free volume properties of silicone rubber ba.ed on poly（di-methylsiloxa.e）（PDMS） wa. studied through therma. a.d cyclic mecha.ica. mea.urements, a. well a. with positron a.nihila.ion lifetime spectroscopy （Pa.S）. The melting tempera.ure of the composites （Tm） a.d the endothermic entha.py of melting （ΔHm） were estima.ed by differentia. sca.ning ca.orimetry （DSC）. Tm a.d the degree of crysta.linity （χc） of PDMS composites were found to decrea.e with increa.ing the CB content. This ca. be expla.ned due to the increa.e in physica. cross-linking which results in a.decrea.e in the crysta.lite thickness. Besides, χc wa. found to be dependent on the filler type. Cyclic stress-stra.n beha.ior of PDMS loa.ed with different contents of filler ha. been studied. Mullins ra.io （RM） wa. found to be dependent on the filler type a.d content. It wa. found tha., RM increa.es with increa.ing the filler content due to the increa.e in physica. cross-linking which results in a.decrea.e in the size of free volume, a. observed through a.decrea.e of the o-Ps lifetime τ3 mea.ured by Pa.S. Moreover, the hysteresis in PDMS-CB composites wa. more pronounced tha. in PDMS-G composites. Furthermore, a.correla.ion wa. esta.lished between the free volume Vf a.d the mecha.ica. properties of PDMS composites conta.ning different fillers. a.nega.ive correla.ion wa. observed between Vf a.d RM.

关键词： Positron a.nihila.ion Positronium Free volume Si-rubber Composite Cyclic mecha.ica. properties.

Dela. a.d Its Time-deriva.ive Dependent Robust Sta.ility of Uncerta.n Neutra. Systems with Sa.ura.ing a.tua.ors

在线全文

学校读者我要写书评

暂无评论

Interna.iona. Journa. of a.toma.ion a.d computing 2010年第4期7卷 455-462页

作者： Fa.ima.el Ha.ussi el Houssa.ne Tissir Presidence of University Sidi Moha.med Ben a.della. La.ora.ory of electronics Signals Systems and Data ProcessingDepartment of PhysicsFaculty of SciencesUniversity Sidi Mohammed Ben Abdellah

This note concerns the problem of the robust sta.ility of uncerta.n neutra. systems with time-va.ying dela. a.d sa.ura.ing a.tua.ors. The system considered is continuous in time with norm bounded pa.a.etric uncerta.nties. By incorpora.ing the free weighing ma.rix a.proa.h developed recently, some new dela.-dependent sta.ility conditions in terms of linea. ma.rix inequa.ities （LMIs） with some tuning pa.a.eters a.e obta.ned. a. estima.e of the doma.n of a.tra.tion of the closed-loop system under a.priori designed controller is proposed. The a.proa.h is ba.ed on a.polytopic description of the a.tua.or sa.ura.ion nonlinea.ities a.d the Lya.unov- Kra.ovskii method. Numerica. exa.ples a.e used to demonstra.e the effectiveness of the proposed design method.

关键词： a.tua.or sa.ura.ion neutra. systems unccrta.nty dela.-dependent condition linea. ma.rix inequa.ity (LMI) time va.ying dela. systems.

Effects of rota.ion a.d ma.netic field on the nonlinea. perista.tic flow of a.second-order fluid in a. a.ymmetric cha.nel through a.porous medium

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2013年第7期22卷 303-313页

作者： a. M. a.d-a.la.S. M. a.o-Da.a. H. D. el-Sha.ra.y Depa.tment of Ma.hema.ics Faculty of ScienceTaif University Depa.tment of Ma.hema.ics Faculty of Science Depa.tment of Ma.hema.ics Faculty of ScienceSouth Valley University

In this pa.er, the effects of both rota.ion a.d ma.netic field of the perista.tic tra.sport of a.second-order fluid through a.porous medium in a.cha.nel a.e studied a.a.ytica.ly a.d computed numerica.ly. The ma.eria. is represented by the constitutive equa.ions for a.second-order fluid. Closed-form solutions under the considera.ion of long wa.elength a.d low Reynolds number is presented. The a.a.ytica. expressions for the pressure gra.ient, pressure rise, friction force, strea. function, shea. stress, a.d velocity a.e obta.ned in the physica. doma.n. The effects of the non-dimensiona. wa.e a.plitude, porosity, ma.netic field, rota.ion, a.d the dimensionless time-mea. flow in the wa.e fra.e a.e a.a.yzed theoretica.ly a.d computed numerica.ly. Numerica. results a.e given a.d illustra.ed gra.hica.ly in ea.h ca.e considered. Compa.ison wa. ma.e with the results obta.ned in the presence a.d a.sence of rota.ion, ma.netic field, a.d porosity. The results indica.e tha. the effects of the non-dimensiona. wa.e a.plitude, porosity, ma.netic field, rota.ion, a.d the dimensionless time-mea. flow a.e very pronounced in the phenomena.

关键词： perista.tic flow second-order fluid ma.netic field porous medium